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* bug#67767: 30.0.50; ERC 5.6: Add track integration to the nicks module
@ 2023-12-11 15:28 J.P.
  2023-12-12  2:18 ` J.P.
                   ` (5 more replies)
  0 siblings, 6 replies; 9+ messages in thread
From: J.P. @ 2023-12-11 15:28 UTC (permalink / raw)
  To: 67767; +Cc: emacs-erc

[-- Attachment #1: Type: text/plain, Size: 5343 bytes --]

Tags: patch

ERC's `nicks' module doesn't currently play nice with `track'. Enabling
it breaks the cycling effect normally occurring among faces in
`erc-track-faces-normal-list' [1]. To address this, I'm proposing we
expose two internal seams:

  1. A function-valued variable for modifying or discarding faces
     gleaned in the narrowed buffer while `track' visits a message.

  2. A buffer-local hash table created on init from the contents of
     `erc-track-faces-normal-list'.

The first brings a small performance penalty and the second a small UX
hiccup [2]. The proposed implementation offsets the first by passing
around more refined data to cut down on some waste during processing.
The second is only currently addressed via doc string, although there's
a public compatibility flag to revert to a related historical behavior,
which dispenses with the issue indirectly.

The only actual addition to the `nicks' module is a user option named
`erc-nicks-track-faces'. It's a boolean that lets you opt out of seeing
nick colors as faces in the mode line indicator. There's also a loosely
related patch that adds some caching to the uniquified name shortening
performed by `track', although it should mainly benefit batch processing
and history playback. Suggestions welcome, as always.

Thanks.


[1] Although, what we typically perceive as this effect is somewhat
    illusory, if not underrealized. See comments preceding the new tests
    in the first patch.

[2] Users will have to toggle the module's minor-mode to update the
    variable mid-session, but we can provide a Custom :set function to
    help with this. Also, there's actually a resource penalty that comes
    with this change too. We can probably use per-server instead of
    per-channel hash tables, or only go per-channel if a local value for
    `erc-track-faces-normal-list' exists on `erc-track-mode' init.


In GNU Emacs 30.0.50 (build 1, x86_64-pc-linux-gnu, GTK+ Version
 3.24.38, cairo version 1.17.6) of 2023-12-06 built on localhost
Repository revision: d8a00879309a3bf62f6ffcae103aa3bdba776ee9
Repository branch: master
Windowing system distributor 'The X.Org Foundation', version 11.0.12014000
System Description: Fedora Linux 37 (Workstation Edition)

Configured using:
 'configure --enable-check-lisp-object-type --enable-checking=yes,glyphs
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[-- Attachment #2: 0001-5.6-Always-promote-normal-faces-in-erc-track.patch --]
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From 1a35b08698dfdfb3cd6568b8dc474ddb45c8da43 Mon Sep 17 00:00:00 2001
From: "F. Jason Park" <jp@neverwas.me>
Date: Sun, 10 Dec 2023 05:33:48 -0800
Subject: [PATCH 1/3] [5.6] Always promote "normal" faces in erc-track

* etc/ERC-NEWS: Add entry for new behavior involving the option
`erc-track-faces-normal-list'.
* lisp/erc/erc-track.el (erc-track-ignore-normal-contenders-p):
New compatibility switch to access pre-5.6 behavior, in which
faces in `erc-track-faces-normal-list' were only considered for
promotion to the mode line if the current face occupying that pole
position wasn't present.
(erc-track-mode, erc-track-enable, erc-track-disable): Add FIXME
comments regarding perceived futility of `erc-server-001-functions and
likely unneeded hook removal.  Run common buffer-local setup and
teardown.
(erc-track--normal-faces): New local variable, a snapshot of
`erc-track-faces-normal-list'.
(erc-track--setup): New function to stash
`erc-track-faces-normal-list' on init.
(erc-track-select-mode-line-face): Offer alternate explanation of
certain particulars in doc string.
(erc-track--select-mode-line-face): New function similar to its public
namesake except that it considers other viable candidates among the
"normal" alternatives.
(erc-track-modified-channels): Only run face selection portion when
faces are actually found.  Use `erc-track--select-mode-line-face'
instead of `erc-track-select-mode-line-face'.
* test/lisp/erc/erc-track-tests.el
(erc-track-select-mode-line-face): New test.
(erc-track-tests--select-mode-line-face): New function.
(erc-track--select-mode-line-face): New test.
---
 etc/ERC-NEWS                     |  22 +++++
 lisp/erc/erc-track.el            | 143 +++++++++++++++++++++++++++----
 test/lisp/erc/erc-track-tests.el | 130 ++++++++++++++++++++++++++++
 3 files changed, 280 insertions(+), 15 deletions(-)

diff --git a/etc/ERC-NEWS b/etc/ERC-NEWS
index 4642c742b0f..a5ebdef508e 100644
--- a/etc/ERC-NEWS
+++ b/etc/ERC-NEWS
@@ -170,6 +170,19 @@ options, like 'erc-command-indicator', have moved to the 'erc-goodies'
 library, although their Custom groups remain the same.  Add
 'command-indicator' to 'erc-modules' to get started.
 
+** Option 'erc-track-faces-normal-list' slightly more influential.
+This option has always been a source of confusion for users, mainly
+because its influence rode heavily on the makeup of faces in a given
+message.  Historically, when a buffer's current mode-line face was a
+member of this option's value, ERC would only swap it out for a fellow
+"normal" if it was absent from message being processed.  Beginning
+with this release, ERC now looks to other ranked and (if necessary)
+unranked "normals" instead of sustaining the same face between
+messages.  This was done to better honor the stated purpose of the
+option, which is to provide consistent visual feedback when buffer
+activity occurs.  If you experience problems with this development,
+see the compatibility flag 'erc-track-ignore-normal-contenders-p'.
+
 ** 'erc-button-alist' and 'erc-nick-popup-alist' have evolved slightly.
 It's no secret that the 'buttons' module treats potential nicknames
 specially.  This is perhaps most evident in its treatment of the
@@ -306,6 +319,15 @@ from 't' to the more useful 'erc-prompt', although the property of the
 same name has been retained and now has a value of 'hidden' when
 disconnected.
 
+*** Lists of faces in buttonized text are no longer nested.
+Previously, when "buttonizing" a new region, ERC would combine faces
+by blindly consing the new onto the existing.  In theory, this kept a
+nice record of all modifications to a given region.  However, it also
+complicated life for other modules wanting to analyze and operate on
+these regions.  Beginning with this release, ERC now merges combined
+faces together when creating buttons, although the odd nested list may
+still crop up here and there.
+
 *** Members of insert- and send-related hooks have been reordered.
 As anyone reading this is no doubt aware, both built-in and
 third-party modules rely on certain hooks for adjusting incoming and
diff --git a/lisp/erc/erc-track.el b/lisp/erc/erc-track.el
index a36b781e04d..a341ea42d24 100644
--- a/lisp/erc/erc-track.el
+++ b/lisp/erc/erc-track.el
@@ -224,10 +224,23 @@ erc-track-faces-normal-list
 message.  This gives a rough indication that active conversations
 are occurring in these channels.
 
+Note that ERC makes a copy of this option when initializing the
+module.  To see your changes reflected mid-session, cycle
+\\[erc-track-mode].
+
 The effect may be disabled by setting this variable to nil."
   :type '(repeat (choice face
 			 (repeat :tag "Combination" face))))
 
+(defvar erc-track-ignore-normal-contenders-p nil
+  "Compatibility flag to promote only exclusively new \"normal\" faces.
+When non-nil, revert to pre-5.6 behavior in which a current
+mode-line face that both outranks and is absent from the current
+message is eligible for replacement with a fellow face from
+`erc-track-faces-normal-list' that does appear in the message.
+By extension, when enabled, never replace the current, reigning
+mode-line face if it's present in the current message.")
+
 (defcustom erc-track-position-in-mode-line 'before-modes
   "Where to show modified channel information in the mode-line.
 
@@ -518,6 +531,9 @@ track
 	 (progn
 	   (add-hook 'window-configuration-change-hook #'erc-user-is-active)
 	   (add-hook 'erc-send-completed-hook #'erc-user-is-active)
+           ;; FIXME find out why this uses `erc-server-001-functions'.
+           ;; `erc-user-is-active' runs when `erc-server-connected' is
+           ;; non-nil.  But this hook usually only runs when it's nil.
 	   (add-hook 'erc-server-001-functions #'erc-user-is-active))
        (erc-track-add-to-mode-line erc-track-position-in-mode-line)
        (erc-update-mode-line)
@@ -528,6 +544,8 @@ track
      ;; enable the tracking keybindings
      (add-hook 'erc-connect-pre-hook #'erc-track-minor-mode-maybe)
      (erc-track-minor-mode-maybe))
+   (add-hook 'erc-mode-hook #'erc-track--setup)
+   (unless erc--updating-modules-p (erc-buffer-do #'erc-track--setup))
    (add-hook 'erc-networks--copy-server-buffer-functions
              #'erc-track--replace-killed-buffer))
   ;; Disable:
@@ -539,6 +557,7 @@ track
 			#'erc-user-is-active)
 	   (remove-hook 'erc-send-completed-hook #'erc-user-is-active)
 	   (remove-hook 'erc-server-001-functions #'erc-user-is-active)
+           ;; FIXME remove this if unused.
 	   (remove-hook 'erc-timer-hook #'erc-user-is-active))
        (remove-hook 'window-configuration-change-hook
 		    #'erc-window-configuration-change)
@@ -548,9 +567,12 @@ track
      (remove-hook 'erc-connect-pre-hook #'erc-track-minor-mode-maybe)
      (when erc-track-minor-mode
        (erc-track-minor-mode -1)))
+   (remove-hook 'erc-mode-hook #'erc-track--setup)
+   (erc-buffer-do #'erc-track--setup)
    (remove-hook 'erc-networks--copy-server-buffer-functions
                 #'erc-track--replace-killed-buffer)))
 
+;; FIXME move this above the module definition.
 (defcustom erc-track-when-inactive nil
   "Enable channel tracking even for visible buffers, if you are inactive."
   :type 'boolean
@@ -562,6 +584,18 @@ erc-track-when-inactive
 	       (erc-track-enable))
 	   (set sym val))))
 
+(defvar-local erc-track--normal-faces nil
+  "Local copy of `erc-track-faces-normal-list' as a hash table.")
+
+(defun erc-track--setup ()
+  "Initialize a buffer for use with the `track' module."
+  (if erc-track-mode
+      (setq erc-track--normal-faces
+            (map-into (mapcar (lambda (f) (cons f t))
+                              erc-track-faces-normal-list)
+                      '(hash-table :test equal)))
+    (kill-local-variable 'erc-track--normal-faces)))
+
 ;;; Visibility
 
 (defvar erc-buffer-activity nil
@@ -766,7 +800,12 @@ erc-track-select-mode-line-face
 face, if a member of `erc-track-faces-normal-list', to be
 replaced with another with lower priority face from NEW-FACES, if
 that face with highest priority in NEW-FACES is also a member of
-`erc-track-faces-normal-list'."
+`erc-track-faces-normal-list'.
+
+To put it another way, when CUR-FACE outranks all NEW-FACES and
+doesn't appear among them, it's eligible to be replaced with a
+fellow \"normal\" from NEW-FACES.  But if it does appear among
+them, it can't be replaced."
   (let ((choice (catch 'face
                   (dolist (candidate erc-track-faces-priority-list)
                     (when (or (equal candidate cur-face)
@@ -785,6 +824,44 @@ erc-track-select-mode-line-face
               choice))
         choice))))
 
+(defun erc-track--select-mode-line-face (cur-face new-faces ranked normals)
+  "Return CUR-FACE or a replacement for displaying in the mode-line, or nil.
+Expect RANKED to be a list of faces and both NORMALS and the car
+of NEW-FACES to be hash tables mapping faces to non-nil values.
+Assume the latter's makeup and that of RANKED to resemble
+`erc-track-face-normal-list' and `erc-track-faces-priority-list'.
+If NEW-FACES has a cdr, expect it to be its car's contents
+ordered from most recently seen (later in the buffer) to
+earliest.  In general, act like `erc-track-select-mode-line-face'
+except reconsider NEW-FACES when CUR-FACE outranks all its
+members.  That is, choose the highest RANKED among NEW-FACES not
+equal to CUR-FACE.  Failing that, choose the first face in
+NORMALS to appear anywhere in NEW-FACES, but only if NEW-FACES
+has a cdr."
+  (cl-check-type erc-track-ignore-normal-contenders-p null)
+  (cl-check-type new-faces cons)
+  (cl-check-type normals hash-table)
+  (when-let ((choice (catch 'face
+                       (dolist (candidate ranked)
+                         (when (or (equal candidate cur-face)
+                                   (gethash candidate (car new-faces)))
+                           (throw 'face candidate))))))
+    (when-let (((equal choice cur-face))
+               ((gethash choice normals))
+               (contender (catch 'face
+                            (progn
+                              (dolist (candidate ranked)
+                                (when (and (not (equal candidate choice))
+                                           (gethash candidate (car new-faces))
+                                           (gethash candidate normals))
+                                  (throw 'face candidate)))
+                              (dolist (f (cdr new-faces))
+                                (when (and (not (equal f choice))
+                                           (gethash f normals))
+                                  (throw 'face f)))))))
+      (setq choice contender))
+    choice))
+
 (defvar erc-track--skipped-msgs '(datestamp)
   "Values of `erc-msg' text prop to ignore.")
 
@@ -819,31 +896,43 @@ erc-track-modified-channels
 	;; (in the car), change its face attribute (in the cddr) if
 	;; necessary.  See `erc-modified-channels-alist' for the
 	;; exact data structure used.
-        (let ((faces (erc-faces-in (buffer-string)))
-              (erc-track-faces-priority-list
-               `(,@erc-track--attn-faces ,@erc-track-faces-priority-list)))
-	  (unless (and
-		   (or (eq erc-track-priority-faces-only 'all)
-		       (member this-channel erc-track-priority-faces-only))
-		   (not (catch 'found
-			  (dolist (f faces)
-			    (when (member f erc-track-faces-priority-list)
-			      (throw 'found t))))))
+        (when-let
+            ((faces (if erc-track-ignore-normal-contenders-p
+                        (erc-faces-in (buffer-string))
+                      (erc-track--get-faces-in-current-message)))
+             (ranked erc-track-faces-priority-list)
+             (normals erc-track--normal-faces)
+             (erc-track-faces-priority-list
+              `(,@erc-track--attn-faces ,@erc-track-faces-priority-list))
+             ((not (and
+                    (or (eq erc-track-priority-faces-only 'all)
+                        (member this-channel erc-track-priority-faces-only))
+                    (not (catch 'found
+                           (dolist (f erc-track-faces-priority-list)
+                             (when (gethash f (or (car-safe faces) faces))
+                               (throw 'found t)))))))))
+          (progn ; FIXME remove `progn' on next major edit
 	    (if (not (assq (current-buffer) erc-modified-channels-alist))
 		;; Add buffer, faces and counts
 		(setq erc-modified-channels-alist
 		      (cons (cons (current-buffer)
 				  (cons
-                                   1 (erc-track-select-mode-line-face
-                                      nil faces)))
+                                   1 (if erc-track-ignore-normal-contenders-p
+                                         (erc-track-select-mode-line-face
+                                          nil faces)
+                                       (erc-track--select-mode-line-face
+                                        nil faces ranked normals))))
 			    erc-modified-channels-alist))
 	      ;; Else modify the face for the buffer, if necessary.
 	      (when faces
 		(let* ((cell (assq (current-buffer)
 				   erc-modified-channels-alist))
 		       (old-face (cddr cell))
-		       (new-face (erc-track-select-mode-line-face
-                                  old-face faces)))
+                       (new-face (if erc-track-ignore-normal-contenders-p
+                                     (erc-track-select-mode-line-face
+                                      old-face faces)
+                                   (erc-track--select-mode-line-face
+                                    old-face faces ranked normals))))
 		  (setcdr cell (cons (1+ (cadr cell)) new-face)))))
 	    ;; And display it
 	    (erc-modified-channels-display)))
@@ -872,6 +961,30 @@ erc-faces-in
 	   (push cur faces)))
     faces))
 
+(defvar erc-track--face-reject-function nil
+  "Function called with face in current buffer to massage or reject.")
+
+(defun erc-track--get-faces-in-current-message ()
+  "Collect all faces in the narrowed buffer.
+Return a cons of a hash table and a list ordered from most
+recently seen to earliest seen."
+  (let ((i (text-property-not-all (point-min) (point-max) 'font-lock-face nil))
+        (seen (make-hash-table :test #'equal))
+        ;;
+        (rfaces ())
+        (faces (make-hash-table :test #'equal)))
+    (while-let ((i)
+                (cur (get-text-property i 'face)))
+      (unless (gethash cur seen)
+        (puthash cur t seen)
+        (when erc-track--face-reject-function
+          (setq cur (funcall erc-track--face-reject-function cur)))
+        (when cur
+          (push cur rfaces)
+          (puthash cur t faces)))
+      (setq i (next-single-property-change i 'font-lock-face)))
+    (cons faces rfaces)))
+
 ;;; Buffer switching
 
 (defvar erc-track-last-non-erc-buffer nil
diff --git a/test/lisp/erc/erc-track-tests.el b/test/lisp/erc/erc-track-tests.el
index ab8d708b721..4477727be8a 100644
--- a/test/lisp/erc/erc-track-tests.el
+++ b/test/lisp/erc/erc-track-tests.el
@@ -120,4 +120,134 @@ erc-track--erc-faces-in
     (should (erc-faces-in str0))
     (should (erc-faces-in str1)) ))
 
+;; This simulates an alternating bold/non-bold [#c] in the mode-line,
+;; i.e., an `erc-modified-channels-alist' that vacillates between
+;;
+;;   ((#<buffer #chan> 42 . erc-default-face))
+;;
+;; and
+;;
+;;   ((#<buffer #chan> 42 erc-nick-default-face erc-default-face))
+;;
+;; This is a fairly typical scenario where consecutive messages
+;; feature speaker and addressee button highlighting and otherwise
+;; plain message bodies.  This mapping of phony to real faces
+;; describes the picture in 5.6:
+;;
+;;   `1': (erc-button erc-default-face)                 ; URL
+;;   `2': (erc-nick-default-face erc-default-face)      ; mention
+;;   `3': erc-default-face                              ; body
+;;   `_': (erc-nick-default-face erc-nick-default-face) ; speaker
+;;
+;; The `_' represents a commonly occurring face (a <speaker>) that's
+;; not present in either option's default (standard) value.  It's a
+;; no-op from the POV of `erc-track-select-mode-line-face'.
+
+(ert-deftest erc-track-select-mode-line-face ()
+
+  ;; Observed (see key above).
+  (let ((erc-track-faces-priority-list '(1 2 3))
+        (erc-track-faces-normal-list   '(1 2 3)))
+
+    (should (equal 2 (erc-track-select-mode-line-face 3 '(2 _ 3))))
+    (should (equal 2 (erc-track-select-mode-line-face 2 '(2 _ 3))))
+    (should (equal 3 (erc-track-select-mode-line-face 2 '(_ 3))))
+    (should (equal 2 (erc-track-select-mode-line-face 3 '(2 3))))
+    (should (equal 3 (erc-track-select-mode-line-face 2 '(3))))
+
+    (should (equal 1 (erc-track-select-mode-line-face 1 '(2 1 3))))
+    (should (equal 1 (erc-track-select-mode-line-face 1 '(1 3))))
+    (should (equal 1 (erc-track-select-mode-line-face 1 '(1 3 2))))
+    (should (equal 1 (erc-track-select-mode-line-face 1 '(3 1)))))
+
+  ;; When the current face outranks all new faces and doesn't appear
+  ;; among them, it's eligible to be replaced with a fellow "normal"
+  ;; from those new faces.  But if it does appear among them, it's
+  ;; never replaced.
+  (let ((erc-track-faces-priority-list '(a b))
+        (erc-track-faces-normal-list   '(a b)))
+
+    (should (equal 'a (erc-track-select-mode-line-face 'a '(b a))))
+    (should (equal 'a (erc-track-select-mode-line-face 'a '(a b))))
+    (should (equal 'a (erc-track-select-mode-line-face 'b '(b a))))
+    (should (equal 'a (erc-track-select-mode-line-face 'b '(a b))))
+
+    (should (equal 'a (erc-track-select-mode-line-face 'b '(a))))
+    (should (equal 'b (erc-track-select-mode-line-face 'a '(b)))))
+
+  ;; The ordering of the "normal" list doesn't matter.
+  (let ((erc-track-faces-priority-list '(a b))
+        (erc-track-faces-normal-list   '(b a)))
+
+    (should (equal 'a (erc-track-select-mode-line-face 'a '(b a))))
+    (should (equal 'a (erc-track-select-mode-line-face 'a '(a b))))
+    (should (equal 'a (erc-track-select-mode-line-face 'b '(b a))))
+    (should (equal 'a (erc-track-select-mode-line-face 'b '(a b))))))
+
+(defun erc-track-tests--select-mode-line-face (ranked normals cases)
+  (setq normals (map-into (mapcar (lambda (f) (cons f t)) normals)
+                          '(hash-table :test equal)))
+  (pcase-dolist (`(,want ,cur-face ,new-faces) cases)
+
+    (ert-info ((format "Observed: {cur: %S, new: %S, want: %S}"
+                       cur-face new-faces want))
+      (setq new-faces (cons (map-into
+                             (mapcar (lambda (f) (cons f t)) new-faces)
+                             '(hash-table :test equal))
+                            (reverse new-faces)))
+      (should (equal want (funcall #'erc-track--select-mode-line-face
+                                   cur-face new-faces ranked normals))))))
+
+;; The main difference between these variants is that with the above,
+;; when given alternating lines like
+;;
+;;  CUR      NEW                          CHOICE
+;;   text     (mention $speaker text)  =>   mention
+;;   mention  ($speaker text)          =>   text
+;;
+;; we see the effect of alternating faces in the indicator.  But when
+;; given consecutive lines with a similar composition, like
+;;
+;;   text     (mention $speaker text)  =>   mention
+;;   text     (mention $speaker text)  =>   mention
+;;
+;; we lose the effect.  With the variant below, we get
+;;
+;;   text     (mention $speaker text)  =>   mention
+;;   text     (mention $speaker text)  =>   text
+;;
+
+(ert-deftest erc-track--select-mode-line-face ()
+  (should-not erc-track-ignore-normal-contenders-p)
+
+  ;; These are the same test cases from the previous test.  The syntax
+  ;; is (expected cur-face new-faces).
+  (erc-track-tests--select-mode-line-face
+   '(1 2 3) '(1 2 3)
+   '((2 3 (2 _ 3))
+     (3 2 (2 _ 3))
+     (3 2 (_ 3))
+     (2 3 (2 3))
+     (3 2 (3))
+     (2 1 (2 1 3))
+     (3 1 (1 3))
+     (2 1 (1 3 2))
+     (3 1 (3 1))))
+
+  (erc-track-tests--select-mode-line-face
+   '(a b) '(a b)
+   '((b a (b a))
+     (b a (a b))
+     (a b (b a))
+     (a b (a b))
+     (a b (a))
+     (b a (b))))
+
+  (erc-track-tests--select-mode-line-face
+   '(a b) '(b a)
+   '((b a (b a))
+     (b a (a b))
+     (a b (b a))
+     (a b (a b)))))
+
 ;;; erc-track-tests.el ends here
-- 
2.42.0


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From 67b729dbb9f7bb5b24d66298a354a7c155abf544 Mon Sep 17 00:00:00 2001
From: "F. Jason Park" <jp@neverwas.me>
Date: Mon, 13 Jun 2022 00:26:22 -0700
Subject: [PATCH 2/3] [5.6] Cache shortened channel names in erc-track

* lisp/erc/erc-track.el (erc-track--shortened-names): New variable to
stash both the latest inputs and most recent result of
`erc-track-shorten-function'.
(erc-track--shortened-names-current-hash,
erc-track--shortened-names-set, erc-track--shortened-names-get): New
pair of generalized-variable functions and helper variable for
accessing and mutating `erc-track--shorten-prefixes'.
(erc-modified-channels-display): Avoid redundant calls to
`erc-track-shorten-function'.  Mainly for use during batch processing.
* test/lisp/erc/erc-track-tests.el
(erc-track--shortened-names): New test.
---
 lisp/erc/erc-track.el            | 42 +++++++++++++++++++++++++++++---
 test/lisp/erc/erc-track-tests.el | 36 +++++++++++++++++++++++++++
 2 files changed, 74 insertions(+), 4 deletions(-)

diff --git a/lisp/erc/erc-track.el b/lisp/erc/erc-track.el
index a341ea42d24..85e7b398573 100644
--- a/lisp/erc/erc-track.el
+++ b/lisp/erc/erc-track.el
@@ -357,6 +357,37 @@ erc-track-add-to-mode-line
 
 ;;; Shortening of names
 
+(defvar erc-track--shortened-names nil
+  "A cons of the last novel name-shortening params and the result.
+The CAR is a hash of environmental inputs such as options and
+parameters passed to `erc-track-shorten-function'.  Its effect is
+only really noticeable during batch processing.")
+
+(defvar erc-track--shortened-names-current-hash nil)
+
+(defun erc-track--shortened-names-set (_ shortened)
+  "Remember SHORTENED names with hash of contextual params."
+  (cl-assert erc-track--shortened-names-current-hash)
+  (setq erc-track--shortened-names
+        (cons erc-track--shortened-names-current-hash shortened)))
+
+(defun erc-track--shortened-names-get (channel-names)
+  "Cache CHANNEL-NAMES with various contextual parameters.
+For now, omit relevant options like `erc-track-shorten-start' and
+friends, even though they do affect the outcome, because they
+likely change too infrequently to matter over sub-second
+intervals and are unlikely to be let-bound or set locally."
+  (when-let ((hash (setq erc-track--shortened-names-current-hash
+                         (sxhash-equal (list channel-names
+                                             (buffer-list)
+                                             erc-track-shorten-function))))
+             (erc-track--shortened-names)
+             ((= hash (car erc-track--shortened-names))))
+    (cdr erc-track--shortened-names)))
+
+(gv-define-simple-setter erc-track--shortened-names-get
+                         erc-track--shortened-names-set)
+
 (defun erc-track-shorten-names (channel-names)
   "Call `erc-unique-channel-names' with the correct parameters.
 This function is a good value for `erc-track-shorten-function'.
@@ -739,10 +770,13 @@ erc-modified-channels-display
                                            (or (buffer-name buf)
                                                ""))
 					 buffers))
-		     (short-names (if (functionp erc-track-shorten-function)
-				      (funcall erc-track-shorten-function
-					       long-names)
-				    long-names))
+                     (erc-track--shortened-names-current-hash nil)
+                     (short-names
+                      (if (functionp erc-track-shorten-function)
+                          (with-memoization
+                              (erc-track--shortened-names-get long-names)
+                            (funcall erc-track-shorten-function long-names))
+                        long-names))
 		     strings)
 		(while buffers
 		  (when (car short-names)
diff --git a/test/lisp/erc/erc-track-tests.el b/test/lisp/erc/erc-track-tests.el
index 4477727be8a..ed3d190928f 100644
--- a/test/lisp/erc/erc-track-tests.el
+++ b/test/lisp/erc/erc-track-tests.el
@@ -104,6 +104,42 @@ erc-track--shorten-aggressive-max
                                       '("#emacs" "#vi"))
             '("#e" "#v"))) ))
 
+(ert-deftest erc-track--shortened-names ()
+  (let (erc-track--shortened-names
+        erc-track--shortened-names-current-hash
+        results)
+
+    (with-memoization (erc-track--shortened-names-get
+                       '("apple" "banana" "cherries"))
+      '("a" "b" "c"))
+    (should (integerp (car erc-track--shortened-names)))
+    (should (equal (cdr erc-track--shortened-names) '("a" "b" "c")))
+    (push erc-track--shortened-names results)
+
+    ;; Redundant call doesn't run.
+    (with-memoization (erc-track--shortened-names-get
+                       '("apple" "banana" "cherries"))
+      (should-not 'run)
+      '("a" "b" "c"))
+    (should (equal erc-track--shortened-names (car results)))
+
+    ;; Change in environment or context forces run.
+    (with-temp-buffer
+      (with-memoization (erc-track--shortened-names-get
+                         '("apple" "banana" "cherries"))
+        '("x" "y" "z")))
+    (should (and (integerp (car erc-track--shortened-names))
+                 (/= (car erc-track--shortened-names) (caar results))))
+    (should (equal (cdr erc-track--shortened-names) '("x" "y" "z")))
+    (push erc-track--shortened-names results)
+
+    (with-memoization (erc-track--shortened-names-get
+                       '("apple" "banana" "cherries"))
+      '("1" "2" "3"))
+    (should (and (integerp (car erc-track--shortened-names))
+                 (/= (car erc-track--shortened-names) (caar results))))
+    (should (equal (cdr erc-track--shortened-names) '("1" "2" "3")))))
+
 (ert-deftest erc-track--erc-faces-in ()
   "`erc-faces-in' should pick up both 'face and 'font-lock-face properties."
   (let ((str0 (copy-sequence "is bold"))
-- 
2.42.0


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From 9466b7ebb1ac4a8316f764e76cc57406d15d0f18 Mon Sep 17 00:00:00 2001
From: "F. Jason Park" <jp@neverwas.me>
Date: Mon, 11 Dec 2023 01:30:48 -0800
Subject: [PATCH 3/3] [5.6] Add erc-track integration to erc-nicks

* lisp/erc/erc-button.el (erc-button-add-button): Use
`erc--merge-prop' instead of `erc-button-add-face' to apply button
faces.  Hold off on deprecating the latter because it provides unique
functionality for nesting faces.
* lisp/erc/erc-nicks.el (erc-nicks-track-faces): New option.
(erc-nicks--highlight-button): Add faces to `erc-track' "normal" table.
(erc-nicks-mode, erc-nicks-enable, erc-nicks-disable): Add and remove
`track' integration.
(erc-nicks--reject-uninterned-faces): New function to remove faces
created by `nicks' from buttonized speakers and mentions.  Conform
to `erc-track--face-reject-function' interface.
(erc-nicks--setup-track-integration): New function.
(erc-nicks--track-nick-face-as-normal): New function to add newly
created face and known likely combination working store of "normal"
faces maintained by `track'.
---
 lisp/erc/erc-button.el |  4 ++--
 lisp/erc/erc-nicks.el  | 33 +++++++++++++++++++++++++++++++++
 2 files changed, 35 insertions(+), 2 deletions(-)

diff --git a/lisp/erc/erc-button.el b/lisp/erc/erc-button.el
index e1c10be53f6..e72ceb705de 100644
--- a/lisp/erc/erc-button.el
+++ b/lisp/erc/erc-button.el
@@ -535,9 +535,9 @@ erc-button-add-button
           (move-marker pos (point))))))
   (if nick-p
       (when erc-button-nickname-face
-        (erc-button-add-face from to erc-button-nickname-face))
+        (erc--merge-prop from to 'font-lock-face erc-button-nickname-face))
     (when erc-button-face
-      (erc-button-add-face from to erc-button-face)))
+      (erc--merge-prop from to 'font-lock-face erc-button-face)))
   (add-text-properties
    from to
    (nconc (and erc-button-mouse-face
diff --git a/lisp/erc/erc-nicks.el b/lisp/erc/erc-nicks.el
index fcd3afdbbc4..3043ad37f78 100644
--- a/lisp/erc/erc-nicks.el
+++ b/lisp/erc/erc-nicks.el
@@ -173,6 +173,10 @@ erc-nicks-key-suffix-format
 like \"@%-012n\"."
   :type 'string)
 
+(defcustom erc-nicks-track-faces t
+  "Show nick faces in the `track' module's portion of the mode line."
+  :type 'boolean)
+
 (defvar erc-nicks--max-skip-search 3 ; make this an option?
   "Max number of faces to visit when testing `erc-nicks-skip-faces'.")
 
@@ -518,6 +522,8 @@ erc-nicks--highlight-button
                                 'font-lock-face))
        (nick (erc-server-user-nickname (erc-button--nick-user nick-object)))
        (out (erc-nicks--highlight nick face)))
+    (when erc-nicks-track-faces
+      (erc-nicks--track-nick-face-as-normal out))
     (setf (erc-button--nick-nickname-face nick-object) out))
   nick-object)
 
@@ -561,6 +567,9 @@ nicks
        erc-nicks--face-table (make-hash-table :test #'equal)))
    (setf (alist-get "Edit face" erc-button--nick-popup-alist nil nil #'equal)
          #'erc-nicks-customize-face)
+   (unless erc-nicks-track-faces
+     (erc-nicks--setup-track-integration)
+     (add-hook 'erc-track-mode #'erc-nicks--setup-track-integration 50 t))
    (advice-add 'widget-create-child-and-convert :filter-args
                #'erc-nicks--redirect-face-widget-link))
   ((kill-local-variable 'erc-nicks--face-table)
@@ -572,6 +581,8 @@ nicks
    (kill-local-variable 'erc-nicks--downcased-skip-nicks)
    (when (fboundp 'erc-button--phantom-users-mode)
      (erc-button--phantom-users-mode -1))
+   (remove-function (local 'erc-track--face-reject-function)
+                    #'erc-nicks--reject-uninterned-faces)
    (remove-function (local 'erc-button--modify-nick-function)
                     #'erc-nicks--highlight-button)
    (setf (alist-get "Edit face"
@@ -693,6 +704,28 @@ erc-nicks--colors-from-faces
                  (color (face-foreground face)))
         (push color out)))))
 
+(defun erc-nicks--reject-uninterned-faces (candidate)
+  "Remove own faces from CANDIDATE if it's a combination of faces."
+  (while-let ((next (car-safe candidate))
+              ((facep next))
+              ((not (intern-soft next))))
+    (setq candidate (cdr candidate)))
+  (if (and (consp candidate) (not (cdr candidate))) (car candidate) candidate))
+
+(defun erc-nicks--setup-track-integration ()
+  "Restore traditional \"alternating normal\" face functionality to mode-line."
+  (cl-assert (not erc-nicks-track-faces))
+  (when (bound-and-true-p erc-track-mode)
+    (add-function :override (local 'erc-track--face-reject-function)
+                  #'erc-nicks--reject-uninterned-faces)))
+
+(defun erc-nicks--track-nick-face-as-normal (face)
+  "Add FACE to local hash table maintained by `track' module."
+  (when (bound-and-true-p erc-track--normal-faces)
+    (puthash `(,@(ensure-list face) erc-default-face) t
+             erc-track--normal-faces)
+    (puthash face t erc-track--normal-faces)))
+
 (provide 'erc-nicks)
 
 ;;; erc-nicks.el ends here
-- 
2.42.0


^ permalink raw reply related	[flat|nested] 9+ messages in thread

* bug#67767: 30.0.50; ERC 5.6: Add track integration to the nicks module
  2023-12-11 15:28 bug#67767: 30.0.50; ERC 5.6: Add track integration to the nicks module J.P.
@ 2023-12-12  2:18 ` J.P.
  2023-12-12 14:49 ` J.P.
                   ` (4 subsequent siblings)
  5 siblings, 0 replies; 9+ messages in thread
From: J.P. @ 2023-12-12  2:18 UTC (permalink / raw)
  To: 67767; +Cc: emacs-erc

"J.P." <jp@neverwas.me> writes:

> [2] Users will have to toggle the module's minor-mode to update the
>     variable mid-session, but we can provide a Custom :set function to
>     help with this. Also, there's actually a resource penalty that comes
>     with this change too. We can probably use per-server instead of
>     per-channel hash tables, or only go per-channel if a local value for
>     `erc-track-faces-normal-list' exists on `erc-track-mode' init.

It turns out these changes may require more planning than originally
budgeted. There's a growing dependency on aspects of the `button' module
that haven't been fully sorted, along with a rather heightened potential
for leaking memory, so I'd rather not move too hastily without good
reason. As such, I'll likely be putting a hold on this until 5.7 and
retitling the bug accordingly.





^ permalink raw reply	[flat|nested] 9+ messages in thread

* bug#67767: 30.0.50; ERC 5.6: Add track integration to the nicks module
  2023-12-11 15:28 bug#67767: 30.0.50; ERC 5.6: Add track integration to the nicks module J.P.
  2023-12-12  2:18 ` J.P.
@ 2023-12-12 14:49 ` J.P.
  2023-12-13 14:06 ` J.P.
                   ` (3 subsequent siblings)
  5 siblings, 0 replies; 9+ messages in thread
From: J.P. @ 2023-12-12 14:49 UTC (permalink / raw)
  To: 67767; +Cc: emacs-erc

[-- Attachment #1: Type: text/plain, Size: 521 bytes --]

v2. Make "normal"-face hash table local to server buffers and double as
cache for inserted `nicks' faces. "Pre-combine" generated `nicks' faces
with `erc-nicks-backing-face' via :include. Overload
`erc-button-add-button' NICKP param (internally) for conveying current
`erc-button--nick' object. Remove `match'-based combo faces from
`erc-track-faces-priority-list' and `erc-track-faces-normal-list'.
Change default of `erc-button-nickname-face' to new face for
distinguishing between button-applied and "speaker" faces.


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From 41117716e971088c62a48ca638102cca069c6751 Mon Sep 17 00:00:00 2001
From: "F. Jason Park" <jp@neverwas.me>
Date: Tue, 12 Dec 2023 06:06:10 -0800
Subject: [PATCH 0/4] *** NOT A PATCH ***

*** BLURB HERE ***

F. Jason Park (4):
  [5.6] Have nick faces :inherit from erc-nicks-backing-face
  [5.7] Promote "normal" faces in erc-track
  [5.7] Cache shortened channel names in erc-track
  [5.7] Add erc-track integration to erc-nicks

 etc/ERC-NEWS                     |  39 +++++
 lisp/erc/erc-button.el           |  49 +++---
 lisp/erc/erc-nicks.el            |  54 ++++++-
 lisp/erc/erc-track.el            | 261 ++++++++++++++++++++++++++++---
 lisp/erc/erc.el                  |   8 +-
 test/lisp/erc/erc-nicks-tests.el |   2 +-
 test/lisp/erc/erc-track-tests.el | 166 ++++++++++++++++++++
 7 files changed, 522 insertions(+), 57 deletions(-)

Interdiff:
diff --git a/etc/ERC-NEWS b/etc/ERC-NEWS
index a5ebdef508e..40e3d5d5638 100644
--- a/etc/ERC-NEWS
+++ b/etc/ERC-NEWS
@@ -197,6 +197,23 @@ s-expressions, which ERC will continue to honor.  Although the default
 lineup remains functionally equivalent, its members have all been
 updated accordingly.
 
+** 'erc-track-faces-priority-list' and 'erc-track-faces-normal-list' slimmed.
+These options have been purged of certain 'button'-related face
+combinations.  Originally added in ERC 5.3, these combinations
+described the effect of "buttonizing" atop faces added by the 'match'
+module, like '(erc-nick-default-face erc-pal-face)'.  However, since
+at least Emacs 27, 'match' has run before 'button' in
+'erc-insert-modify-hook', meaning such permutations aren't possible.
+
+More importantly, users who've customized either of these options
+should update them with the new default value of the option
+'erc-button-nickname-face'.  Like 'erc-nick-default-face', which it
+replaces, the new 'erc-button-nick-default-face' is also a "real"
+face.  Its sole reason for existing is to make it easier for users and
+modules to distinguish between basic buttonized faces and
+'erc-nick-default-face', which is now reserved to mean the base
+"speaker" face.
+
 ** Option 'erc-query-on-unjoined-chan-privmsg' restored and renamed.
 This option was accidentally removed from the default client in ERC
 5.5 and was thus prevented from influencing PRIVMSG routing.  It's now
diff --git a/lisp/erc/erc-button.el b/lisp/erc/erc-button.el
index e72ceb705de..fc2511bad42 100644
--- a/lisp/erc/erc-button.el
+++ b/lisp/erc/erc-button.el
@@ -70,6 +70,11 @@ erc-button
   "ERC button face."
   :group 'erc-faces)
 
+(defface erc-button-nick-default-face '((t :inherit erc-nick-default-face))
+  "Default face for a buttonized nickname."
+  :package-version '(ERC . "5.7") ; FIXME sync on release
+  :group 'erc-faces)
+
 (defcustom erc-button-face 'erc-button
   "Face used for highlighting buttons in ERC buffers.
 
@@ -78,8 +83,9 @@ erc-button-face
   :type 'face
   :group 'erc-faces)
 
-(defcustom erc-button-nickname-face 'erc-nick-default-face
+(defcustom erc-button-nickname-face 'erc-button-nick-default-face
   "Face used for ERC nickname buttons."
+  :package-version '(ERC . "5.7") ; FIXME sync on release
   :type 'face
   :group 'erc-faces)
 
@@ -363,7 +369,8 @@ erc-button--nick
   ( nickname-face erc-button-nickname-face :type symbol
     :documentation "Temp `erc-button-nickname-face' while buttonizing.")
   ( mouse-face erc-button-mouse-face :type symbol
-    :documentation "Temp `erc-button-mouse-face' while buttonizing."))
+    :documentation "Function to return possibly cached face.")
+  ( face-cache nil :type (or null function)))
 
 ;; This variable is intended to serve as a "core" to be wrapped by
 ;; (built-in) modules during setup.  It's unclear whether
@@ -454,8 +461,7 @@ erc-button-add-nickname-buttons
                      (erc-bounds-of-word-at-point)))
          (word (buffer-substring-no-properties (car bounds) (cdr bounds)))
          (down (erc-downcase word)))
-      (let* ((erc-button-mouse-face erc-button-mouse-face)
-             (erc-button-nickname-face erc-button-nickname-face)
+      (let* ((nick-obj t)
              (cuser (and erc-channel-users
                          (or (gethash down erc-channel-users)
                              (funcall erc-button--fallback-cmem-function
@@ -464,19 +470,15 @@ erc-button-add-nickname-buttons
                        (and erc-server-users (gethash down erc-server-users))))
              (data (list word)))
         (when (or (not (functionp form))
-                  (and-let* ((user)
-                             (obj (funcall form (make-erc-button--nick
-                                                 :bounds bounds :data data
-                                                 :downcased down :user user
-                                                 :cuser (cdr cuser)))))
-                    (setq erc-button-mouse-face ; might be null
-                          (erc-button--nick-mouse-face obj)
-                          erc-button-nickname-face ; might be null
-                          (erc-button--nick-nickname-face obj)
-                          data (erc-button--nick-data obj)
-                          bounds (erc-button--nick-bounds obj))))
+                  (and user
+                       (setq nick-obj (funcall form (make-erc-button--nick
+                                                     :bounds bounds :data data
+                                                     :downcased down :user user
+                                                     :cuser (cdr cuser)))
+                             data (erc-button--nick-data nick-obj)
+                             bounds (erc-button--nick-bounds nick-obj))))
           (erc-button-add-button (car bounds) (cdr bounds) (nth 3 entry)
-                                 'nickp data))))))
+                                 nick-obj data))))))
 
 (defun erc-button-add-buttons-1 (regexp entry)
   "Search through the buffer for matches to ENTRY and add buttons."
@@ -535,13 +537,20 @@ erc-button-add-button
           (move-marker pos (point))))))
   (if nick-p
       (when erc-button-nickname-face
-        (erc--merge-prop from to 'font-lock-face erc-button-nickname-face))
+        (erc--merge-prop from to 'font-lock-face
+                         (or (and (erc-button--nick-p nick-p)
+                                  (erc-button--nick-nickname-face nick-p))
+                             erc-button-nickname-face)
+                         nil (and (erc-button--nick-p nick-p)
+                                  (erc-button--nick-face-cache nick-p))))
     (when erc-button-face
       (erc--merge-prop from to 'font-lock-face erc-button-face)))
   (add-text-properties
    from to
-   (nconc (and erc-button-mouse-face
-               (list 'mouse-face erc-button-mouse-face))
+   (nconc (and-let* ((face (or (and (erc-button--nick-p nick-p)
+                                    (erc-button--nick-mouse-face nick-p))
+                               erc-button-mouse-face)))
+            (list 'mouse-face face))
           (list 'erc-callback fun)
           (list 'keymap erc-button-keymap)
           (list 'rear-nonsticky t)
diff --git a/lisp/erc/erc-nicks.el b/lisp/erc/erc-nicks.el
index 3043ad37f78..92dd03912e6 100644
--- a/lisp/erc/erc-nicks.el
+++ b/lisp/erc/erc-nicks.el
@@ -458,7 +458,9 @@ erc-nicks--get-face
           (put new-face 'erc-nicks--nick nick)
           (put new-face 'erc-nicks--netid erc-networks--id)
           (put new-face 'erc-nicks--key key)
-          (face-spec-set new-face `((t :foreground ,color)) 'face-defface-spec)
+          (face-spec-set new-face `((t :foreground ,color
+                                       :inherit ,erc-nicks-backing-face))
+                         'face-defface-spec)
           (set-face-documentation
            new-face (format "Internal face for %s on %s." nick (erc-network)))
           (puthash nick new-face table)))))
@@ -507,12 +509,8 @@ erc-nicks--highlight
              ((not (and base-face
                         (erc-nicks--skip-p base-face erc-nicks-skip-faces
                                            erc-nicks--max-skip-search))))
-             (key (erc-nicks--gen-key-from-format-spec trimmed))
-             (out (erc-nicks--get-face trimmed key)))
-    (if (or (null erc-nicks-backing-face)
-            (eq base-face erc-nicks-backing-face))
-        out
-      (cons out (erc-list erc-nicks-backing-face)))))
+             (key (erc-nicks--gen-key-from-format-spec trimmed)))
+    (erc-nicks--get-face trimmed key)))
 
 (defun erc-nicks--highlight-button (nick-object)
   "Possibly add face to `erc-button--nick-user' NICK-OBJECT."
@@ -522,9 +520,12 @@ erc-nicks--highlight-button
                                 'font-lock-face))
        (nick (erc-server-user-nickname (erc-button--nick-user nick-object)))
        (out (erc-nicks--highlight nick face)))
-    (when erc-nicks-track-faces
-      (erc-nicks--track-nick-face-as-normal out))
-    (setf (erc-button--nick-nickname-face nick-object) out))
+    (setf (erc-button--nick-nickname-face nick-object) out
+          ;;
+          (erc-button--nick-face-cache nick-object)
+          (and erc-nicks-track-faces
+               (bound-and-true-p erc-track--normal-faces)
+               #'erc-nicks--remember-face-for-track)))
   nick-object)
 
 (define-erc-module nicks nil
@@ -719,12 +720,16 @@ erc-nicks--setup-track-integration
     (add-function :override (local 'erc-track--face-reject-function)
                   #'erc-nicks--reject-uninterned-faces)))
 
-(defun erc-nicks--track-nick-face-as-normal (face)
+(defun erc-nicks--remember-face-for-track (face)
   "Add FACE to local hash table maintained by `track' module."
-  (when (bound-and-true-p erc-track--normal-faces)
-    (puthash `(,@(ensure-list face) erc-default-face) t
-             erc-track--normal-faces)
-    (puthash face t erc-track--normal-faces)))
+  (defvar erc-track--normal-faces)
+  (cl-assert erc-track--normal-faces)
+  (or (gethash face erc-track--normal-faces)
+      (if-let ((sym (or (car-safe face) face))
+               ((symbolp sym))
+               ((get sym 'erc-nicks--key)))
+          (puthash face face erc-track--normal-faces)
+        face)))
 
 (provide 'erc-nicks)
 
diff --git a/lisp/erc/erc-track.el b/lisp/erc/erc-track.el
index 85e7b398573..4c3c7ca49a5 100644
--- a/lisp/erc/erc-track.el
+++ b/lisp/erc/erc-track.el
@@ -161,23 +161,39 @@ erc-track-use-faces
 \(e.g. `erc-pal-face' is used if a pal sent a message to that channel.)"
   :type 'boolean)
 
+;; Historically, `erc-track-faces-priority-list' had members
+;; describing the effect of buttonizing atop faces from `match', e.g.,
+;; (erc-nick-default-face erc-pal-face).  However, since at least
+;; Emacs 27, `match' has done its damage after `button' in
+;; `erc-insert-modify-hook', meaning such permutations cannot exist.
+(defvar erc-track--old-nick-button-faces
+  '((erc-nick-default-face erc-default-face))
+  "List of obsolete nick button faces.")
+
+(defun erc-track--massage-nick-button-faces (val)
+  "Update members of face list VAL to have the default nick button face.
+In ERC 5.7, it changed from `erc-current-nick-face' to
+`erc-button-nick-default-face'."
+  (mapcar (lambda (f)
+            (if (and (eq (car-safe f) 'erc-nick-default-face)
+                     (member f erc-track--old-nick-button-faces))
+                (cons 'erc-button-nick-default-face (cdr f))
+              f))
+          val))
+
 (defcustom erc-track-faces-priority-list
   '(erc-error-face
-    (erc-nick-default-face erc-current-nick-face)
     erc-current-nick-face
     erc-keyword-face
-    (erc-nick-default-face erc-pal-face)
     erc-pal-face
     erc-nick-msg-face
     erc-direct-msg-face
     (erc-button erc-default-face)
-    (erc-nick-default-face erc-dangerous-host-face)
     erc-dangerous-host-face
     erc-nick-default-face
-    (erc-nick-default-face erc-default-face)
+    (erc-button-nick-default-face erc-default-face)
     erc-default-face
     erc-action-face
-    (erc-nick-default-face erc-fool-face)
     erc-fool-face
     erc-notice-face
     erc-input-face
@@ -188,6 +204,9 @@ erc-track-faces-priority-list
 
 Note that ERC prioritizes certain faces reserved for critical
 messages regardless of this option's value."
+  :package-version '(ERC . "5.7") ; FIXME sync on release
+  :set (lambda (sym val)
+         (set-default sym (erc-track--massage-nick-button-faces val)))
   :type (erc--with-dependent-type-match
          (repeat (choice face (repeat :tag "Combination" face)))
          erc-button))
@@ -209,10 +228,9 @@ erc-track-priority-faces-only
 
 (defcustom erc-track-faces-normal-list
   '((erc-button erc-default-face)
-    (erc-nick-default-face erc-dangerous-host-face)
     erc-dangerous-host-face
     erc-nick-default-face
-    (erc-nick-default-face erc-default-face)
+    (erc-button-nick-default-face erc-default-face)
     erc-default-face
     erc-action-face)
   "A list of faces considered to be part of normal conversations.
@@ -229,6 +247,9 @@ erc-track-faces-normal-list
 \\[erc-track-mode].
 
 The effect may be disabled by setting this variable to nil."
+  :package-version '(ERC . "5.7") ; FIXME sync on release
+  :set (lambda (sym val)
+         (set-default sym (erc-track--massage-nick-button-faces val)))
   :type '(repeat (choice face
 			 (repeat :tag "Combination" face))))
 
@@ -619,12 +640,46 @@ erc-track--normal-faces
   "Local copy of `erc-track-faces-normal-list' as a hash table.")
 
 (defun erc-track--setup ()
-  "Initialize a buffer for use with the `track' module."
+  "Initialize a buffer for use with the `track' module.
+If this is a server buffer or `erc-track-faces-normal-list' is
+locally bound, create a new `erc-track--normal-faces' for the
+current buffer.  Otherwise, set the local value to the server
+buffer's."
   (if erc-track-mode
-      (setq erc-track--normal-faces
-            (map-into (mapcar (lambda (f) (cons f t))
-                              erc-track-faces-normal-list)
-                      '(hash-table :test equal)))
+      (let ((existing (erc-with-server-buffer erc-track--normal-faces))
+            (localp (and erc--target
+                         (local-variable-p 'erc-track-faces-normal-list)))
+            warnp table)
+        (unless (or erc--target (not (or (bound-and-true-p erc-button-mode)
+                                         (memq 'button erc-modules))))
+          (dolist (opt '(erc-track-faces-normal-list
+                         erc-track-faces-priority-list))
+            (when (seq-some
+                   (lambda (f)
+                     (and (eq (car-safe f) 'erc-nick-default-face)
+                          (member f erc-track--old-nick-button-faces)))
+                   (symbol-value opt))
+              (push opt warnp)
+              (set opt (erc-track--massage-nick-button-faces
+                        (symbol-value opt)))))
+          (when warnp
+            (erc--warn-once-before-connect 'erc-track-mode
+              (if (cdr warnp) "Options " "Option ")
+              (mapconcat (lambda (o) (format "`%S'" o)) warnp " and ")
+              (if (cdr warnp) " contain" " contains")
+              " obsolete list-style faces intended to match buttonized"
+              " nicknames. To silence this warning, please update members"
+              " with `%S' at their head, like %S, by converting them to %S."
+              " ERC has done this for you for this session."
+              'erc-nick-default-face '(erc-nick-default-face foo)
+              '(erc-button-nick-default-face foo))))
+        (when (or (null existing) localp)
+          (setq table (map-into (mapcar (lambda (f) (cons f f))
+                                        erc-track-faces-normal-list)
+                                '(hash-table :test equal :weakness value))))
+        (setq erc-track--normal-faces (or table existing))
+        (unless (or localp existing)
+          (erc-with-server-buffer (setq erc-track--normal-faces table))))
     (kill-local-variable 'erc-track--normal-faces)))
 
 ;;; Visibility
@@ -858,40 +913,47 @@ erc-track-select-mode-line-face
               choice))
         choice))))
 
-(defun erc-track--select-mode-line-face (cur-face new-faces ranked normals)
+(define-inline erc-track--gett (table-or-function key)
+  "Look up KEY via TABLE-OR-FUNCTION."
+  (inline-quote
+   (if (functionp ,table-or-function)
+       (funcall ,table-or-function ,key)
+     (gethash ,key ,table-or-function))))
+
+(defun erc-track--select-mode-line-face (cur-face new-faces ranks normals)
   "Return CUR-FACE or a replacement for displaying in the mode-line, or nil.
-Expect RANKED to be a list of faces and both NORMALS and the car
+Expect RANKS to be a list of faces and both NORMALS and the car
 of NEW-FACES to be hash tables mapping faces to non-nil values.
-Assume the latter's makeup and that of RANKED to resemble
+Assume the latter's makeup and that of RANKS to resemble
 `erc-track-face-normal-list' and `erc-track-faces-priority-list'.
 If NEW-FACES has a cdr, expect it to be its car's contents
 ordered from most recently seen (later in the buffer) to
 earliest.  In general, act like `erc-track-select-mode-line-face'
 except reconsider NEW-FACES when CUR-FACE outranks all its
-members.  That is, choose the highest RANKED among NEW-FACES not
+members.  That is, choose the highest RANKS among NEW-FACES not
 equal to CUR-FACE.  Failing that, choose the first face in
 NORMALS to appear anywhere in NEW-FACES, but only if NEW-FACES
-has a cdr."
+has a cdr.  If NORMALS is a function, call it with the name of a
+face to query membership."
   (cl-check-type erc-track-ignore-normal-contenders-p null)
   (cl-check-type new-faces cons)
-  (cl-check-type normals hash-table)
   (when-let ((choice (catch 'face
-                       (dolist (candidate ranked)
+                       (dolist (candidate ranks)
                          (when (or (equal candidate cur-face)
                                    (gethash candidate (car new-faces)))
                            (throw 'face candidate))))))
     (when-let (((equal choice cur-face))
-               ((gethash choice normals))
+               ((erc-track--gett normals choice))
                (contender (catch 'face
                             (progn
-                              (dolist (candidate ranked)
+                              (dolist (candidate ranks)
                                 (when (and (not (equal candidate choice))
                                            (gethash candidate (car new-faces))
-                                           (gethash candidate normals))
+                                           (erc-track--gett normals candidate))
                                   (throw 'face candidate)))
                               (dolist (f (cdr new-faces))
                                 (when (and (not (equal f choice))
-                                           (gethash f normals))
+                                           (erc-track--gett normals f))
                                   (throw 'face f)))))))
       (setq choice contender))
     choice))
@@ -934,15 +996,15 @@ erc-track-modified-channels
             ((faces (if erc-track-ignore-normal-contenders-p
                         (erc-faces-in (buffer-string))
                       (erc-track--get-faces-in-current-message)))
-             (ranked erc-track-faces-priority-list)
              (normals erc-track--normal-faces)
              (erc-track-faces-priority-list
               `(,@erc-track--attn-faces ,@erc-track-faces-priority-list))
+             (ranks erc-track-faces-priority-list)
              ((not (and
                     (or (eq erc-track-priority-faces-only 'all)
                         (member this-channel erc-track-priority-faces-only))
                     (not (catch 'found
-                           (dolist (f erc-track-faces-priority-list)
+                           (dolist (f ranks)
                              (when (gethash f (or (car-safe faces) faces))
                                (throw 'found t)))))))))
           (progn ; FIXME remove `progn' on next major edit
@@ -955,7 +1017,7 @@ erc-track-modified-channels
                                          (erc-track-select-mode-line-face
                                           nil faces)
                                        (erc-track--select-mode-line-face
-                                        nil faces ranked normals))))
+                                        nil faces ranks normals))))
 			    erc-modified-channels-alist))
 	      ;; Else modify the face for the buffer, if necessary.
 	      (when faces
@@ -966,7 +1028,7 @@ erc-track-modified-channels
                                      (erc-track-select-mode-line-face
                                       old-face faces)
                                    (erc-track--select-mode-line-face
-                                    old-face faces ranked normals))))
+                                    old-face faces ranks normals))))
 		  (setcdr cell (cons (1+ (cadr cell)) new-face)))))
 	    ;; And display it
 	    (erc-modified-channels-display)))
diff --git a/lisp/erc/erc.el b/lisp/erc/erc.el
index 62fdc0ad6e8..2734c602fa2 100644
--- a/lisp/erc/erc.el
+++ b/lisp/erc/erc.el
@@ -3351,12 +3351,14 @@ erc--merge-text-properties-p
 ;; values and optionally dispense archetypal constants in their place
 ;; in order to ensure all occurrences of some list (a b) across all
 ;; text-properties in all ERC buffers are actually the same object.
-(defun erc--merge-prop (from to prop val &optional object)
+(defun erc--merge-prop (from to prop val &optional object cache-fn)
   "Combine existing PROP values with VAL between FROM and TO in OBJECT.
 For spans where PROP is non-nil, cons VAL onto the existing
 value, ensuring a proper list.  Otherwise, just set PROP to VAL.
 When VAL is itself a list, prepend its members onto an existing
-value.  See also `erc-button-add-face'."
+value.  Call CACHE-FN, when given, with the new value for prop.
+It must return a suitable replacement or the same value.  See
+also `erc-button-add-face'."
   (let ((old (get-text-property from prop object))
         (pos from)
         (end (next-single-property-change from prop object to))
@@ -3370,6 +3372,8 @@ erc--merge-prop
                           (append val (ensure-list old))
                         (cons val (ensure-list old))))
                   val))
+      (when cache-fn
+        (setq new (funcall cache-fn new)))
       (put-text-property pos end prop new object)
       (setq pos end
             old (get-text-property pos prop object)
diff --git a/test/lisp/erc/erc-nicks-tests.el b/test/lisp/erc/erc-nicks-tests.el
index 35264a23caa..54882278139 100644
--- a/test/lisp/erc/erc-nicks-tests.el
+++ b/test/lisp/erc/erc-nicks-tests.el
@@ -409,7 +409,7 @@ erc-nicks-list-faces
              (push-button)
              (should (search-forward-regexp
                       (rx "Foreground: #" (group (+ xdigit)) eol)))
-             (forward-button 1)
+             (forward-button 2) ; skip Inherit:...
              (push-button))
 
            (ert-info ("First entry's sample is rendered correctly")
-- 
2.42.0


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From 214ad79b5cfdb8e9baa9ad7f7ec2a38634b46081 Mon Sep 17 00:00:00 2001
From: "F. Jason Park" <jp@neverwas.me>
Date: Mon, 11 Dec 2023 20:24:17 -0800
Subject: [PATCH 1/4] [5.6] Have nick faces :inherit from
 erc-nicks-backing-face

* lisp/erc/erc-nicks.el (erc-nicks--get-face): Make generated face
:inherit from `erc-nicks-backing-face'.
(erc-nicks--highlight): Just return the generated face instead of
combining it with `erc-nicks-backing-face' or the existing face in the
buffer.
* test/lisp/erc/erc-nicks-tests.el (erc-nicks-list-faces): Skip
"Inherit: " button.
---
 lisp/erc/erc-nicks.el            | 12 +++++-------
 test/lisp/erc/erc-nicks-tests.el |  2 +-
 2 files changed, 6 insertions(+), 8 deletions(-)

diff --git a/lisp/erc/erc-nicks.el b/lisp/erc/erc-nicks.el
index fcd3afdbbc4..2f0c3261266 100644
--- a/lisp/erc/erc-nicks.el
+++ b/lisp/erc/erc-nicks.el
@@ -454,7 +454,9 @@ erc-nicks--get-face
           (put new-face 'erc-nicks--nick nick)
           (put new-face 'erc-nicks--netid erc-networks--id)
           (put new-face 'erc-nicks--key key)
-          (face-spec-set new-face `((t :foreground ,color)) 'face-defface-spec)
+          (face-spec-set new-face `((t :foreground ,color
+                                       :inherit ,erc-nicks-backing-face))
+                         'face-defface-spec)
           (set-face-documentation
            new-face (format "Internal face for %s on %s." nick (erc-network)))
           (puthash nick new-face table)))))
@@ -503,12 +505,8 @@ erc-nicks--highlight
              ((not (and base-face
                         (erc-nicks--skip-p base-face erc-nicks-skip-faces
                                            erc-nicks--max-skip-search))))
-             (key (erc-nicks--gen-key-from-format-spec trimmed))
-             (out (erc-nicks--get-face trimmed key)))
-    (if (or (null erc-nicks-backing-face)
-            (eq base-face erc-nicks-backing-face))
-        out
-      (cons out (erc-list erc-nicks-backing-face)))))
+             (key (erc-nicks--gen-key-from-format-spec trimmed)))
+    (erc-nicks--get-face trimmed key)))
 
 (defun erc-nicks--highlight-button (nick-object)
   "Possibly add face to `erc-button--nick-user' NICK-OBJECT."
diff --git a/test/lisp/erc/erc-nicks-tests.el b/test/lisp/erc/erc-nicks-tests.el
index 35264a23caa..54882278139 100644
--- a/test/lisp/erc/erc-nicks-tests.el
+++ b/test/lisp/erc/erc-nicks-tests.el
@@ -409,7 +409,7 @@ erc-nicks-list-faces
              (push-button)
              (should (search-forward-regexp
                       (rx "Foreground: #" (group (+ xdigit)) eol)))
-             (forward-button 1)
+             (forward-button 2) ; skip Inherit:...
              (push-button))
 
            (ert-info ("First entry's sample is rendered correctly")
-- 
2.42.0


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From 666e2cd2546c7a9bda48f5857b032f97accac6fb Mon Sep 17 00:00:00 2001
From: "F. Jason Park" <jp@neverwas.me>
Date: Sun, 10 Dec 2023 05:33:48 -0800
Subject: [PATCH 2/4] [5.7] Promote "normal" faces in erc-track

* etc/ERC-NEWS: Add entry for new behavior involving the option
`erc-track-faces-normal-list'.
* lisp/erc/erc-button.el (erc-button-nick-default-face): New face to
serve as default for `erc-button-nickname-face'.
(erc-button-nickname-face): Change default value to
`erc-button-nick-default-face'.
* lisp/erc/erc-track.el (erc-track--old-nick-button-faces,
erc-track--massage-nick-button-faces): New supporting variable and
function to serve as Custom :set function for priority and "normal"
face-list options.
(erc-track-faces-priority-list, erc-track-faces-normal-list): Change
values for `match' module faces to feature
`erc-button-nick-default-face' instead of `erc-nick-default-face'.
(erc-track-ignore-normal-contenders-p): New compatibility switch to
access pre-5.6 behavior, in which faces in
`erc-track-faces-normal-list' were only considered for promotion to
the mode line if the current face occupying that pole position wasn't
present.
(erc-track-mode, erc-track-enable, erc-track-disable): Add FIXME
comments regarding perceived futility of `erc-server-001-functions and
likely unneeded hook removal.  Run common buffer-local setup and
teardown.
(erc-track--normal-faces): New local variable, a snapshot of
`erc-track-faces-normal-list'.
(erc-track--setup): New function to stash
`erc-track-faces-normal-list' on init.
(erc-track-select-mode-line-face): Offer alternate explanation of
certain particulars in doc string.
(erc-track--gett): New helper function.
(erc-track--select-mode-line-face): New function similar to its public
namesake except that it considers other viable candidates among the
"normal" alternatives.
(erc-track-modified-channels): Only run face selection portion when
faces are actually found.  Use `erc-track--select-mode-line-face'
instead of `erc-track-select-mode-line-face'.
* test/lisp/erc/erc-track-tests.el
(erc-track-select-mode-line-face): New test.
(erc-track-tests--select-mode-line-face): New function.
(erc-track--select-mode-line-face): New test.  (Bug#67767)
---
 etc/ERC-NEWS                     |  39 ++++++
 lisp/erc/erc-button.el           |   8 +-
 lisp/erc/erc-track.el            | 219 +++++++++++++++++++++++++++----
 test/lisp/erc/erc-track-tests.el | 130 ++++++++++++++++++
 4 files changed, 373 insertions(+), 23 deletions(-)

diff --git a/etc/ERC-NEWS b/etc/ERC-NEWS
index 4642c742b0f..40e3d5d5638 100644
--- a/etc/ERC-NEWS
+++ b/etc/ERC-NEWS
@@ -170,6 +170,19 @@ options, like 'erc-command-indicator', have moved to the 'erc-goodies'
 library, although their Custom groups remain the same.  Add
 'command-indicator' to 'erc-modules' to get started.
 
+** Option 'erc-track-faces-normal-list' slightly more influential.
+This option has always been a source of confusion for users, mainly
+because its influence rode heavily on the makeup of faces in a given
+message.  Historically, when a buffer's current mode-line face was a
+member of this option's value, ERC would only swap it out for a fellow
+"normal" if it was absent from message being processed.  Beginning
+with this release, ERC now looks to other ranked and (if necessary)
+unranked "normals" instead of sustaining the same face between
+messages.  This was done to better honor the stated purpose of the
+option, which is to provide consistent visual feedback when buffer
+activity occurs.  If you experience problems with this development,
+see the compatibility flag 'erc-track-ignore-normal-contenders-p'.
+
 ** 'erc-button-alist' and 'erc-nick-popup-alist' have evolved slightly.
 It's no secret that the 'buttons' module treats potential nicknames
 specially.  This is perhaps most evident in its treatment of the
@@ -184,6 +197,23 @@ s-expressions, which ERC will continue to honor.  Although the default
 lineup remains functionally equivalent, its members have all been
 updated accordingly.
 
+** 'erc-track-faces-priority-list' and 'erc-track-faces-normal-list' slimmed.
+These options have been purged of certain 'button'-related face
+combinations.  Originally added in ERC 5.3, these combinations
+described the effect of "buttonizing" atop faces added by the 'match'
+module, like '(erc-nick-default-face erc-pal-face)'.  However, since
+at least Emacs 27, 'match' has run before 'button' in
+'erc-insert-modify-hook', meaning such permutations aren't possible.
+
+More importantly, users who've customized either of these options
+should update them with the new default value of the option
+'erc-button-nickname-face'.  Like 'erc-nick-default-face', which it
+replaces, the new 'erc-button-nick-default-face' is also a "real"
+face.  Its sole reason for existing is to make it easier for users and
+modules to distinguish between basic buttonized faces and
+'erc-nick-default-face', which is now reserved to mean the base
+"speaker" face.
+
 ** Option 'erc-query-on-unjoined-chan-privmsg' restored and renamed.
 This option was accidentally removed from the default client in ERC
 5.5 and was thus prevented from influencing PRIVMSG routing.  It's now
@@ -306,6 +336,15 @@ from 't' to the more useful 'erc-prompt', although the property of the
 same name has been retained and now has a value of 'hidden' when
 disconnected.
 
+*** Lists of faces in buttonized text are no longer nested.
+Previously, when "buttonizing" a new region, ERC would combine faces
+by blindly consing the new onto the existing.  In theory, this kept a
+nice record of all modifications to a given region.  However, it also
+complicated life for other modules wanting to analyze and operate on
+these regions.  Beginning with this release, ERC now merges combined
+faces together when creating buttons, although the odd nested list may
+still crop up here and there.
+
 *** Members of insert- and send-related hooks have been reordered.
 As anyone reading this is no doubt aware, both built-in and
 third-party modules rely on certain hooks for adjusting incoming and
diff --git a/lisp/erc/erc-button.el b/lisp/erc/erc-button.el
index e1c10be53f6..f10d7a2fce7 100644
--- a/lisp/erc/erc-button.el
+++ b/lisp/erc/erc-button.el
@@ -70,6 +70,11 @@ erc-button
   "ERC button face."
   :group 'erc-faces)
 
+(defface erc-button-nick-default-face '((t :inherit erc-nick-default-face))
+  "Default face for a buttonized nickname."
+  :package-version '(ERC . "5.7") ; FIXME sync on release
+  :group 'erc-faces)
+
 (defcustom erc-button-face 'erc-button
   "Face used for highlighting buttons in ERC buffers.
 
@@ -78,8 +83,9 @@ erc-button-face
   :type 'face
   :group 'erc-faces)
 
-(defcustom erc-button-nickname-face 'erc-nick-default-face
+(defcustom erc-button-nickname-face 'erc-button-nick-default-face
   "Face used for ERC nickname buttons."
+  :package-version '(ERC . "5.7") ; FIXME sync on release
   :type 'face
   :group 'erc-faces)
 
diff --git a/lisp/erc/erc-track.el b/lisp/erc/erc-track.el
index a36b781e04d..478eabaa961 100644
--- a/lisp/erc/erc-track.el
+++ b/lisp/erc/erc-track.el
@@ -161,23 +161,39 @@ erc-track-use-faces
 \(e.g. `erc-pal-face' is used if a pal sent a message to that channel.)"
   :type 'boolean)
 
+;; Historically, `erc-track-faces-priority-list' had members
+;; describing the effect of buttonizing atop faces from `match', e.g.,
+;; (erc-nick-default-face erc-pal-face).  However, since at least
+;; Emacs 27, `match' has done its damage after `button' in
+;; `erc-insert-modify-hook', meaning such permutations cannot exist.
+(defvar erc-track--old-nick-button-faces
+  '((erc-nick-default-face erc-default-face))
+  "List of obsolete nick button faces.")
+
+(defun erc-track--massage-nick-button-faces (val)
+  "Update members of face list VAL to have the default nick button face.
+In ERC 5.7, it changed from `erc-current-nick-face' to
+`erc-button-nick-default-face'."
+  (mapcar (lambda (f)
+            (if (and (eq (car-safe f) 'erc-nick-default-face)
+                     (member f erc-track--old-nick-button-faces))
+                (cons 'erc-button-nick-default-face (cdr f))
+              f))
+          val))
+
 (defcustom erc-track-faces-priority-list
   '(erc-error-face
-    (erc-nick-default-face erc-current-nick-face)
     erc-current-nick-face
     erc-keyword-face
-    (erc-nick-default-face erc-pal-face)
     erc-pal-face
     erc-nick-msg-face
     erc-direct-msg-face
     (erc-button erc-default-face)
-    (erc-nick-default-face erc-dangerous-host-face)
     erc-dangerous-host-face
     erc-nick-default-face
-    (erc-nick-default-face erc-default-face)
+    (erc-button-nick-default-face erc-default-face)
     erc-default-face
     erc-action-face
-    (erc-nick-default-face erc-fool-face)
     erc-fool-face
     erc-notice-face
     erc-input-face
@@ -188,6 +204,9 @@ erc-track-faces-priority-list
 
 Note that ERC prioritizes certain faces reserved for critical
 messages regardless of this option's value."
+  :package-version '(ERC . "5.7") ; FIXME sync on release
+  :set (lambda (sym val)
+         (set-default sym (erc-track--massage-nick-button-faces val)))
   :type (erc--with-dependent-type-match
          (repeat (choice face (repeat :tag "Combination" face)))
          erc-button))
@@ -209,10 +228,9 @@ erc-track-priority-faces-only
 
 (defcustom erc-track-faces-normal-list
   '((erc-button erc-default-face)
-    (erc-nick-default-face erc-dangerous-host-face)
     erc-dangerous-host-face
     erc-nick-default-face
-    (erc-nick-default-face erc-default-face)
+    (erc-button-nick-default-face erc-default-face)
     erc-default-face
     erc-action-face)
   "A list of faces considered to be part of normal conversations.
@@ -224,10 +242,26 @@ erc-track-faces-normal-list
 message.  This gives a rough indication that active conversations
 are occurring in these channels.
 
+Note that ERC makes a copy of this option when initializing the
+module.  To see your changes reflected mid-session, cycle
+\\[erc-track-mode].
+
 The effect may be disabled by setting this variable to nil."
+  :package-version '(ERC . "5.7") ; FIXME sync on release
+  :set (lambda (sym val)
+         (set-default sym (erc-track--massage-nick-button-faces val)))
   :type '(repeat (choice face
 			 (repeat :tag "Combination" face))))
 
+(defvar erc-track-ignore-normal-contenders-p nil
+  "Compatibility flag to promote only exclusively new \"normal\" faces.
+When non-nil, revert to pre-5.6 behavior in which a current
+mode-line face that both outranks and is absent from the current
+message is eligible for replacement with a fellow face from
+`erc-track-faces-normal-list' that does appear in the message.
+By extension, when enabled, never replace the current, reigning
+mode-line face if it's present in the current message.")
+
 (defcustom erc-track-position-in-mode-line 'before-modes
   "Where to show modified channel information in the mode-line.
 
@@ -518,6 +552,9 @@ track
 	 (progn
 	   (add-hook 'window-configuration-change-hook #'erc-user-is-active)
 	   (add-hook 'erc-send-completed-hook #'erc-user-is-active)
+           ;; FIXME find out why this uses `erc-server-001-functions'.
+           ;; `erc-user-is-active' runs when `erc-server-connected' is
+           ;; non-nil.  But this hook usually only runs when it's nil.
 	   (add-hook 'erc-server-001-functions #'erc-user-is-active))
        (erc-track-add-to-mode-line erc-track-position-in-mode-line)
        (erc-update-mode-line)
@@ -528,6 +565,8 @@ track
      ;; enable the tracking keybindings
      (add-hook 'erc-connect-pre-hook #'erc-track-minor-mode-maybe)
      (erc-track-minor-mode-maybe))
+   (add-hook 'erc-mode-hook #'erc-track--setup)
+   (unless erc--updating-modules-p (erc-buffer-do #'erc-track--setup))
    (add-hook 'erc-networks--copy-server-buffer-functions
              #'erc-track--replace-killed-buffer))
   ;; Disable:
@@ -539,6 +578,7 @@ track
 			#'erc-user-is-active)
 	   (remove-hook 'erc-send-completed-hook #'erc-user-is-active)
 	   (remove-hook 'erc-server-001-functions #'erc-user-is-active)
+           ;; FIXME remove this if unused.
 	   (remove-hook 'erc-timer-hook #'erc-user-is-active))
        (remove-hook 'window-configuration-change-hook
 		    #'erc-window-configuration-change)
@@ -548,9 +588,12 @@ track
      (remove-hook 'erc-connect-pre-hook #'erc-track-minor-mode-maybe)
      (when erc-track-minor-mode
        (erc-track-minor-mode -1)))
+   (remove-hook 'erc-mode-hook #'erc-track--setup)
+   (erc-buffer-do #'erc-track--setup)
    (remove-hook 'erc-networks--copy-server-buffer-functions
                 #'erc-track--replace-killed-buffer)))
 
+;; FIXME move this above the module definition.
 (defcustom erc-track-when-inactive nil
   "Enable channel tracking even for visible buffers, if you are inactive."
   :type 'boolean
@@ -562,6 +605,52 @@ erc-track-when-inactive
 	       (erc-track-enable))
 	   (set sym val))))
 
+(defvar-local erc-track--normal-faces nil
+  "Local copy of `erc-track-faces-normal-list' as a hash table.")
+
+(defun erc-track--setup ()
+  "Initialize a buffer for use with the `track' module.
+If this is a server buffer or `erc-track-faces-normal-list' is
+locally bound, create a new `erc-track--normal-faces' for the
+current buffer.  Otherwise, set the local value to the server
+buffer's."
+  (if erc-track-mode
+      (let ((existing (erc-with-server-buffer erc-track--normal-faces))
+            (localp (and erc--target
+                         (local-variable-p 'erc-track-faces-normal-list)))
+            warnp table)
+        (unless (or erc--target (not (or (bound-and-true-p erc-button-mode)
+                                         (memq 'button erc-modules))))
+          (dolist (opt '(erc-track-faces-normal-list
+                         erc-track-faces-priority-list))
+            (when (seq-some
+                   (lambda (f)
+                     (and (eq (car-safe f) 'erc-nick-default-face)
+                          (member f erc-track--old-nick-button-faces)))
+                   (symbol-value opt))
+              (push opt warnp)
+              (set opt (erc-track--massage-nick-button-faces
+                        (symbol-value opt)))))
+          (when warnp
+            (erc--warn-once-before-connect 'erc-track-mode
+              (if (cdr warnp) "Options " "Option ")
+              (mapconcat (lambda (o) (format "`%S'" o)) warnp " and ")
+              (if (cdr warnp) " contain" " contains")
+              " obsolete list-style faces intended to match buttonized"
+              " nicknames. To silence this warning, please update members"
+              " with `%S' at their head, like %S, by converting them to %S."
+              " ERC has done this for you for this session."
+              'erc-nick-default-face '(erc-nick-default-face foo)
+              '(erc-button-nick-default-face foo))))
+        (when (or (null existing) localp)
+          (setq table (map-into (mapcar (lambda (f) (cons f f))
+                                        erc-track-faces-normal-list)
+                                '(hash-table :test equal :weakness value))))
+        (setq erc-track--normal-faces (or table existing))
+        (unless (or localp existing)
+          (erc-with-server-buffer (setq erc-track--normal-faces table))))
+    (kill-local-variable 'erc-track--normal-faces)))
+
 ;;; Visibility
 
 (defvar erc-buffer-activity nil
@@ -766,7 +855,12 @@ erc-track-select-mode-line-face
 face, if a member of `erc-track-faces-normal-list', to be
 replaced with another with lower priority face from NEW-FACES, if
 that face with highest priority in NEW-FACES is also a member of
-`erc-track-faces-normal-list'."
+`erc-track-faces-normal-list'.
+
+To put it another way, when CUR-FACE outranks all NEW-FACES and
+doesn't appear among them, it's eligible to be replaced with a
+fellow \"normal\" from NEW-FACES.  But if it does appear among
+them, it can't be replaced."
   (let ((choice (catch 'face
                   (dolist (candidate erc-track-faces-priority-list)
                     (when (or (equal candidate cur-face)
@@ -785,6 +879,51 @@ erc-track-select-mode-line-face
               choice))
         choice))))
 
+(define-inline erc-track--gett (table-or-function key)
+  "Look up KEY via TABLE-OR-FUNCTION."
+  (inline-quote
+   (if (functionp ,table-or-function)
+       (funcall ,table-or-function ,key)
+     (gethash ,key ,table-or-function))))
+
+(defun erc-track--select-mode-line-face (cur-face new-faces ranks normals)
+  "Return CUR-FACE or a replacement for displaying in the mode-line, or nil.
+Expect RANKS to be a list of faces and both NORMALS and the car
+of NEW-FACES to be hash tables mapping faces to non-nil values.
+Assume the latter's makeup and that of RANKS to resemble
+`erc-track-face-normal-list' and `erc-track-faces-priority-list'.
+If NEW-FACES has a cdr, expect it to be its car's contents
+ordered from most recently seen (later in the buffer) to
+earliest.  In general, act like `erc-track-select-mode-line-face'
+except reconsider NEW-FACES when CUR-FACE outranks all its
+members.  That is, choose the highest RANKS among NEW-FACES not
+equal to CUR-FACE.  Failing that, choose the first face in
+NORMALS to appear anywhere in NEW-FACES, but only if NEW-FACES
+has a cdr.  If NORMALS is a function, call it with the name of a
+face to query membership."
+  (cl-check-type erc-track-ignore-normal-contenders-p null)
+  (cl-check-type new-faces cons)
+  (when-let ((choice (catch 'face
+                       (dolist (candidate ranks)
+                         (when (or (equal candidate cur-face)
+                                   (gethash candidate (car new-faces)))
+                           (throw 'face candidate))))))
+    (when-let (((equal choice cur-face))
+               ((erc-track--gett normals choice))
+               (contender (catch 'face
+                            (progn
+                              (dolist (candidate ranks)
+                                (when (and (not (equal candidate choice))
+                                           (gethash candidate (car new-faces))
+                                           (erc-track--gett normals candidate))
+                                  (throw 'face candidate)))
+                              (dolist (f (cdr new-faces))
+                                (when (and (not (equal f choice))
+                                           (erc-track--gett normals f))
+                                  (throw 'face f)))))))
+      (setq choice contender))
+    choice))
+
 (defvar erc-track--skipped-msgs '(datestamp)
   "Values of `erc-msg' text prop to ignore.")
 
@@ -819,31 +958,43 @@ erc-track-modified-channels
 	;; (in the car), change its face attribute (in the cddr) if
 	;; necessary.  See `erc-modified-channels-alist' for the
 	;; exact data structure used.
-        (let ((faces (erc-faces-in (buffer-string)))
-              (erc-track-faces-priority-list
-               `(,@erc-track--attn-faces ,@erc-track-faces-priority-list)))
-	  (unless (and
-		   (or (eq erc-track-priority-faces-only 'all)
-		       (member this-channel erc-track-priority-faces-only))
-		   (not (catch 'found
-			  (dolist (f faces)
-			    (when (member f erc-track-faces-priority-list)
-			      (throw 'found t))))))
+        (when-let
+            ((faces (if erc-track-ignore-normal-contenders-p
+                        (erc-faces-in (buffer-string))
+                      (erc-track--get-faces-in-current-message)))
+             (normals erc-track--normal-faces)
+             (erc-track-faces-priority-list
+              `(,@erc-track--attn-faces ,@erc-track-faces-priority-list))
+             (ranks erc-track-faces-priority-list)
+             ((not (and
+                    (or (eq erc-track-priority-faces-only 'all)
+                        (member this-channel erc-track-priority-faces-only))
+                    (not (catch 'found
+                           (dolist (f ranks)
+                             (when (gethash f (or (car-safe faces) faces))
+                               (throw 'found t)))))))))
+          (progn ; FIXME remove `progn' on next major edit
 	    (if (not (assq (current-buffer) erc-modified-channels-alist))
 		;; Add buffer, faces and counts
 		(setq erc-modified-channels-alist
 		      (cons (cons (current-buffer)
 				  (cons
-                                   1 (erc-track-select-mode-line-face
-                                      nil faces)))
+                                   1 (if erc-track-ignore-normal-contenders-p
+                                         (erc-track-select-mode-line-face
+                                          nil faces)
+                                       (erc-track--select-mode-line-face
+                                        nil faces ranks normals))))
 			    erc-modified-channels-alist))
 	      ;; Else modify the face for the buffer, if necessary.
 	      (when faces
 		(let* ((cell (assq (current-buffer)
 				   erc-modified-channels-alist))
 		       (old-face (cddr cell))
-		       (new-face (erc-track-select-mode-line-face
-                                  old-face faces)))
+                       (new-face (if erc-track-ignore-normal-contenders-p
+                                     (erc-track-select-mode-line-face
+                                      old-face faces)
+                                   (erc-track--select-mode-line-face
+                                    old-face faces ranks normals))))
 		  (setcdr cell (cons (1+ (cadr cell)) new-face)))))
 	    ;; And display it
 	    (erc-modified-channels-display)))
@@ -872,6 +1023,30 @@ erc-faces-in
 	   (push cur faces)))
     faces))
 
+(defvar erc-track--face-reject-function nil
+  "Function called with face in current buffer to massage or reject.")
+
+(defun erc-track--get-faces-in-current-message ()
+  "Collect all faces in the narrowed buffer.
+Return a cons of a hash table and a list ordered from most
+recently seen to earliest seen."
+  (let ((i (text-property-not-all (point-min) (point-max) 'font-lock-face nil))
+        (seen (make-hash-table :test #'equal))
+        ;;
+        (rfaces ())
+        (faces (make-hash-table :test #'equal)))
+    (while-let ((i)
+                (cur (get-text-property i 'face)))
+      (unless (gethash cur seen)
+        (puthash cur t seen)
+        (when erc-track--face-reject-function
+          (setq cur (funcall erc-track--face-reject-function cur)))
+        (when cur
+          (push cur rfaces)
+          (puthash cur t faces)))
+      (setq i (next-single-property-change i 'font-lock-face)))
+    (cons faces rfaces)))
+
 ;;; Buffer switching
 
 (defvar erc-track-last-non-erc-buffer nil
diff --git a/test/lisp/erc/erc-track-tests.el b/test/lisp/erc/erc-track-tests.el
index ab8d708b721..4477727be8a 100644
--- a/test/lisp/erc/erc-track-tests.el
+++ b/test/lisp/erc/erc-track-tests.el
@@ -120,4 +120,134 @@ erc-track--erc-faces-in
     (should (erc-faces-in str0))
     (should (erc-faces-in str1)) ))
 
+;; This simulates an alternating bold/non-bold [#c] in the mode-line,
+;; i.e., an `erc-modified-channels-alist' that vacillates between
+;;
+;;   ((#<buffer #chan> 42 . erc-default-face))
+;;
+;; and
+;;
+;;   ((#<buffer #chan> 42 erc-nick-default-face erc-default-face))
+;;
+;; This is a fairly typical scenario where consecutive messages
+;; feature speaker and addressee button highlighting and otherwise
+;; plain message bodies.  This mapping of phony to real faces
+;; describes the picture in 5.6:
+;;
+;;   `1': (erc-button erc-default-face)                 ; URL
+;;   `2': (erc-nick-default-face erc-default-face)      ; mention
+;;   `3': erc-default-face                              ; body
+;;   `_': (erc-nick-default-face erc-nick-default-face) ; speaker
+;;
+;; The `_' represents a commonly occurring face (a <speaker>) that's
+;; not present in either option's default (standard) value.  It's a
+;; no-op from the POV of `erc-track-select-mode-line-face'.
+
+(ert-deftest erc-track-select-mode-line-face ()
+
+  ;; Observed (see key above).
+  (let ((erc-track-faces-priority-list '(1 2 3))
+        (erc-track-faces-normal-list   '(1 2 3)))
+
+    (should (equal 2 (erc-track-select-mode-line-face 3 '(2 _ 3))))
+    (should (equal 2 (erc-track-select-mode-line-face 2 '(2 _ 3))))
+    (should (equal 3 (erc-track-select-mode-line-face 2 '(_ 3))))
+    (should (equal 2 (erc-track-select-mode-line-face 3 '(2 3))))
+    (should (equal 3 (erc-track-select-mode-line-face 2 '(3))))
+
+    (should (equal 1 (erc-track-select-mode-line-face 1 '(2 1 3))))
+    (should (equal 1 (erc-track-select-mode-line-face 1 '(1 3))))
+    (should (equal 1 (erc-track-select-mode-line-face 1 '(1 3 2))))
+    (should (equal 1 (erc-track-select-mode-line-face 1 '(3 1)))))
+
+  ;; When the current face outranks all new faces and doesn't appear
+  ;; among them, it's eligible to be replaced with a fellow "normal"
+  ;; from those new faces.  But if it does appear among them, it's
+  ;; never replaced.
+  (let ((erc-track-faces-priority-list '(a b))
+        (erc-track-faces-normal-list   '(a b)))
+
+    (should (equal 'a (erc-track-select-mode-line-face 'a '(b a))))
+    (should (equal 'a (erc-track-select-mode-line-face 'a '(a b))))
+    (should (equal 'a (erc-track-select-mode-line-face 'b '(b a))))
+    (should (equal 'a (erc-track-select-mode-line-face 'b '(a b))))
+
+    (should (equal 'a (erc-track-select-mode-line-face 'b '(a))))
+    (should (equal 'b (erc-track-select-mode-line-face 'a '(b)))))
+
+  ;; The ordering of the "normal" list doesn't matter.
+  (let ((erc-track-faces-priority-list '(a b))
+        (erc-track-faces-normal-list   '(b a)))
+
+    (should (equal 'a (erc-track-select-mode-line-face 'a '(b a))))
+    (should (equal 'a (erc-track-select-mode-line-face 'a '(a b))))
+    (should (equal 'a (erc-track-select-mode-line-face 'b '(b a))))
+    (should (equal 'a (erc-track-select-mode-line-face 'b '(a b))))))
+
+(defun erc-track-tests--select-mode-line-face (ranked normals cases)
+  (setq normals (map-into (mapcar (lambda (f) (cons f t)) normals)
+                          '(hash-table :test equal)))
+  (pcase-dolist (`(,want ,cur-face ,new-faces) cases)
+
+    (ert-info ((format "Observed: {cur: %S, new: %S, want: %S}"
+                       cur-face new-faces want))
+      (setq new-faces (cons (map-into
+                             (mapcar (lambda (f) (cons f t)) new-faces)
+                             '(hash-table :test equal))
+                            (reverse new-faces)))
+      (should (equal want (funcall #'erc-track--select-mode-line-face
+                                   cur-face new-faces ranked normals))))))
+
+;; The main difference between these variants is that with the above,
+;; when given alternating lines like
+;;
+;;  CUR      NEW                          CHOICE
+;;   text     (mention $speaker text)  =>   mention
+;;   mention  ($speaker text)          =>   text
+;;
+;; we see the effect of alternating faces in the indicator.  But when
+;; given consecutive lines with a similar composition, like
+;;
+;;   text     (mention $speaker text)  =>   mention
+;;   text     (mention $speaker text)  =>   mention
+;;
+;; we lose the effect.  With the variant below, we get
+;;
+;;   text     (mention $speaker text)  =>   mention
+;;   text     (mention $speaker text)  =>   text
+;;
+
+(ert-deftest erc-track--select-mode-line-face ()
+  (should-not erc-track-ignore-normal-contenders-p)
+
+  ;; These are the same test cases from the previous test.  The syntax
+  ;; is (expected cur-face new-faces).
+  (erc-track-tests--select-mode-line-face
+   '(1 2 3) '(1 2 3)
+   '((2 3 (2 _ 3))
+     (3 2 (2 _ 3))
+     (3 2 (_ 3))
+     (2 3 (2 3))
+     (3 2 (3))
+     (2 1 (2 1 3))
+     (3 1 (1 3))
+     (2 1 (1 3 2))
+     (3 1 (3 1))))
+
+  (erc-track-tests--select-mode-line-face
+   '(a b) '(a b)
+   '((b a (b a))
+     (b a (a b))
+     (a b (b a))
+     (a b (a b))
+     (a b (a))
+     (b a (b))))
+
+  (erc-track-tests--select-mode-line-face
+   '(a b) '(b a)
+   '((b a (b a))
+     (b a (a b))
+     (a b (b a))
+     (a b (a b)))))
+
 ;;; erc-track-tests.el ends here
-- 
2.42.0


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From 712d8426f1fe86e141485698dee2c71f960fd8ce Mon Sep 17 00:00:00 2001
From: "F. Jason Park" <jp@neverwas.me>
Date: Mon, 13 Jun 2022 00:26:22 -0700
Subject: [PATCH 3/4] [5.7] Cache shortened channel names in erc-track

* lisp/erc/erc-track.el (erc-track--shortened-names): New variable to
stash both the latest inputs and most recent result of
`erc-track-shorten-function'.
(erc-track--shortened-names-current-hash,
erc-track--shortened-names-set, erc-track--shortened-names-get): New
pair of generalized-variable functions and helper variable for
accessing and mutating `erc-track--shorten-prefixes'.
(erc-modified-channels-display): Avoid redundant calls to
`erc-track-shorten-function'.  Mainly for use during batch processing.
* test/lisp/erc/erc-track-tests.el
(erc-track--shortened-names): New test.  (Bug#67767)
---
 lisp/erc/erc-track.el            | 42 +++++++++++++++++++++++++++++---
 test/lisp/erc/erc-track-tests.el | 36 +++++++++++++++++++++++++++
 2 files changed, 74 insertions(+), 4 deletions(-)

diff --git a/lisp/erc/erc-track.el b/lisp/erc/erc-track.el
index 478eabaa961..4c3c7ca49a5 100644
--- a/lisp/erc/erc-track.el
+++ b/lisp/erc/erc-track.el
@@ -378,6 +378,37 @@ erc-track-add-to-mode-line
 
 ;;; Shortening of names
 
+(defvar erc-track--shortened-names nil
+  "A cons of the last novel name-shortening params and the result.
+The CAR is a hash of environmental inputs such as options and
+parameters passed to `erc-track-shorten-function'.  Its effect is
+only really noticeable during batch processing.")
+
+(defvar erc-track--shortened-names-current-hash nil)
+
+(defun erc-track--shortened-names-set (_ shortened)
+  "Remember SHORTENED names with hash of contextual params."
+  (cl-assert erc-track--shortened-names-current-hash)
+  (setq erc-track--shortened-names
+        (cons erc-track--shortened-names-current-hash shortened)))
+
+(defun erc-track--shortened-names-get (channel-names)
+  "Cache CHANNEL-NAMES with various contextual parameters.
+For now, omit relevant options like `erc-track-shorten-start' and
+friends, even though they do affect the outcome, because they
+likely change too infrequently to matter over sub-second
+intervals and are unlikely to be let-bound or set locally."
+  (when-let ((hash (setq erc-track--shortened-names-current-hash
+                         (sxhash-equal (list channel-names
+                                             (buffer-list)
+                                             erc-track-shorten-function))))
+             (erc-track--shortened-names)
+             ((= hash (car erc-track--shortened-names))))
+    (cdr erc-track--shortened-names)))
+
+(gv-define-simple-setter erc-track--shortened-names-get
+                         erc-track--shortened-names-set)
+
 (defun erc-track-shorten-names (channel-names)
   "Call `erc-unique-channel-names' with the correct parameters.
 This function is a good value for `erc-track-shorten-function'.
@@ -794,10 +825,13 @@ erc-modified-channels-display
                                            (or (buffer-name buf)
                                                ""))
 					 buffers))
-		     (short-names (if (functionp erc-track-shorten-function)
-				      (funcall erc-track-shorten-function
-					       long-names)
-				    long-names))
+                     (erc-track--shortened-names-current-hash nil)
+                     (short-names
+                      (if (functionp erc-track-shorten-function)
+                          (with-memoization
+                              (erc-track--shortened-names-get long-names)
+                            (funcall erc-track-shorten-function long-names))
+                        long-names))
 		     strings)
 		(while buffers
 		  (when (car short-names)
diff --git a/test/lisp/erc/erc-track-tests.el b/test/lisp/erc/erc-track-tests.el
index 4477727be8a..ed3d190928f 100644
--- a/test/lisp/erc/erc-track-tests.el
+++ b/test/lisp/erc/erc-track-tests.el
@@ -104,6 +104,42 @@ erc-track--shorten-aggressive-max
                                       '("#emacs" "#vi"))
             '("#e" "#v"))) ))
 
+(ert-deftest erc-track--shortened-names ()
+  (let (erc-track--shortened-names
+        erc-track--shortened-names-current-hash
+        results)
+
+    (with-memoization (erc-track--shortened-names-get
+                       '("apple" "banana" "cherries"))
+      '("a" "b" "c"))
+    (should (integerp (car erc-track--shortened-names)))
+    (should (equal (cdr erc-track--shortened-names) '("a" "b" "c")))
+    (push erc-track--shortened-names results)
+
+    ;; Redundant call doesn't run.
+    (with-memoization (erc-track--shortened-names-get
+                       '("apple" "banana" "cherries"))
+      (should-not 'run)
+      '("a" "b" "c"))
+    (should (equal erc-track--shortened-names (car results)))
+
+    ;; Change in environment or context forces run.
+    (with-temp-buffer
+      (with-memoization (erc-track--shortened-names-get
+                         '("apple" "banana" "cherries"))
+        '("x" "y" "z")))
+    (should (and (integerp (car erc-track--shortened-names))
+                 (/= (car erc-track--shortened-names) (caar results))))
+    (should (equal (cdr erc-track--shortened-names) '("x" "y" "z")))
+    (push erc-track--shortened-names results)
+
+    (with-memoization (erc-track--shortened-names-get
+                       '("apple" "banana" "cherries"))
+      '("1" "2" "3"))
+    (should (and (integerp (car erc-track--shortened-names))
+                 (/= (car erc-track--shortened-names) (caar results))))
+    (should (equal (cdr erc-track--shortened-names) '("1" "2" "3")))))
+
 (ert-deftest erc-track--erc-faces-in ()
   "`erc-faces-in' should pick up both 'face and 'font-lock-face properties."
   (let ((str0 (copy-sequence "is bold"))
-- 
2.42.0


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From 41117716e971088c62a48ca638102cca069c6751 Mon Sep 17 00:00:00 2001
From: "F. Jason Park" <jp@neverwas.me>
Date: Mon, 11 Dec 2023 01:30:48 -0800
Subject: [PATCH 4/4] [5.7] Add erc-track integration to erc-nicks

* lisp/erc/erc-button.el (erc-button--nick): Add `face-cache' slot.
(erc-button-add-nickname-buttons): Pass `erc-button--nick' object, if
created' as the boolean NICK-P parameter when calling
`erc-button-add-button'.  Keeping the latter ignorant
`erc-button--nick' is of course preferable, but some coordination is
now required to convey and use the face cache.  We could introduce an
abstraction, like a local variable, if this becomes an issue.
(erc-button-add-button): Use `erc--merge-prop' instead of
`erc-button-add-face' to apply button faces.  Hold off on deprecating
the latter because it provides unique functionality for nesting faces.
Also, consult NICK-P if it's an `erc-button--nick' object for the
various overriding faces it knows about.
* lisp/erc/erc-nicks.el (erc-nicks-track-faces): New option.
(erc-nicks--highlight-button): Set the `face-cache' slot of the
`erc-button--nick' object when `track' is loaded and initialized.
(erc-nicks-mode, erc-nicks-enable, erc-nicks-disable): Add and remove
`track' integration.
(erc-nicks--reject-uninterned-faces): New function to remove faces
created by `nicks' from buttonized speakers and mentions.  Conform
to `erc-track--face-reject-function' interface.
(erc-nicks--setup-track-integration): New function.
(erc-nicks--remember-face-for-track): New function to cache
nick faces owned by this module.  (Bug#67767)
---
 lisp/erc/erc-button.el | 41 ++++++++++++++++++++++-------------------
 lisp/erc/erc-nicks.el  | 42 +++++++++++++++++++++++++++++++++++++++++-
 lisp/erc/erc.el        |  8 ++++++--
 3 files changed, 69 insertions(+), 22 deletions(-)

diff --git a/lisp/erc/erc-button.el b/lisp/erc/erc-button.el
index f10d7a2fce7..fc2511bad42 100644
--- a/lisp/erc/erc-button.el
+++ b/lisp/erc/erc-button.el
@@ -369,7 +369,8 @@ erc-button--nick
   ( nickname-face erc-button-nickname-face :type symbol
     :documentation "Temp `erc-button-nickname-face' while buttonizing.")
   ( mouse-face erc-button-mouse-face :type symbol
-    :documentation "Temp `erc-button-mouse-face' while buttonizing."))
+    :documentation "Function to return possibly cached face.")
+  ( face-cache nil :type (or null function)))
 
 ;; This variable is intended to serve as a "core" to be wrapped by
 ;; (built-in) modules during setup.  It's unclear whether
@@ -460,8 +461,7 @@ erc-button-add-nickname-buttons
                      (erc-bounds-of-word-at-point)))
          (word (buffer-substring-no-properties (car bounds) (cdr bounds)))
          (down (erc-downcase word)))
-      (let* ((erc-button-mouse-face erc-button-mouse-face)
-             (erc-button-nickname-face erc-button-nickname-face)
+      (let* ((nick-obj t)
              (cuser (and erc-channel-users
                          (or (gethash down erc-channel-users)
                              (funcall erc-button--fallback-cmem-function
@@ -470,19 +470,15 @@ erc-button-add-nickname-buttons
                        (and erc-server-users (gethash down erc-server-users))))
              (data (list word)))
         (when (or (not (functionp form))
-                  (and-let* ((user)
-                             (obj (funcall form (make-erc-button--nick
-                                                 :bounds bounds :data data
-                                                 :downcased down :user user
-                                                 :cuser (cdr cuser)))))
-                    (setq erc-button-mouse-face ; might be null
-                          (erc-button--nick-mouse-face obj)
-                          erc-button-nickname-face ; might be null
-                          (erc-button--nick-nickname-face obj)
-                          data (erc-button--nick-data obj)
-                          bounds (erc-button--nick-bounds obj))))
+                  (and user
+                       (setq nick-obj (funcall form (make-erc-button--nick
+                                                     :bounds bounds :data data
+                                                     :downcased down :user user
+                                                     :cuser (cdr cuser)))
+                             data (erc-button--nick-data nick-obj)
+                             bounds (erc-button--nick-bounds nick-obj))))
           (erc-button-add-button (car bounds) (cdr bounds) (nth 3 entry)
-                                 'nickp data))))))
+                                 nick-obj data))))))
 
 (defun erc-button-add-buttons-1 (regexp entry)
   "Search through the buffer for matches to ENTRY and add buttons."
@@ -541,13 +537,20 @@ erc-button-add-button
           (move-marker pos (point))))))
   (if nick-p
       (when erc-button-nickname-face
-        (erc-button-add-face from to erc-button-nickname-face))
+        (erc--merge-prop from to 'font-lock-face
+                         (or (and (erc-button--nick-p nick-p)
+                                  (erc-button--nick-nickname-face nick-p))
+                             erc-button-nickname-face)
+                         nil (and (erc-button--nick-p nick-p)
+                                  (erc-button--nick-face-cache nick-p))))
     (when erc-button-face
-      (erc-button-add-face from to erc-button-face)))
+      (erc--merge-prop from to 'font-lock-face erc-button-face)))
   (add-text-properties
    from to
-   (nconc (and erc-button-mouse-face
-               (list 'mouse-face erc-button-mouse-face))
+   (nconc (and-let* ((face (or (and (erc-button--nick-p nick-p)
+                                    (erc-button--nick-mouse-face nick-p))
+                               erc-button-mouse-face)))
+            (list 'mouse-face face))
           (list 'erc-callback fun)
           (list 'keymap erc-button-keymap)
           (list 'rear-nonsticky t)
diff --git a/lisp/erc/erc-nicks.el b/lisp/erc/erc-nicks.el
index 2f0c3261266..92dd03912e6 100644
--- a/lisp/erc/erc-nicks.el
+++ b/lisp/erc/erc-nicks.el
@@ -173,6 +173,10 @@ erc-nicks-key-suffix-format
 like \"@%-012n\"."
   :type 'string)
 
+(defcustom erc-nicks-track-faces t
+  "Show nick faces in the `track' module's portion of the mode line."
+  :type 'boolean)
+
 (defvar erc-nicks--max-skip-search 3 ; make this an option?
   "Max number of faces to visit when testing `erc-nicks-skip-faces'.")
 
@@ -516,7 +520,12 @@ erc-nicks--highlight-button
                                 'font-lock-face))
        (nick (erc-server-user-nickname (erc-button--nick-user nick-object)))
        (out (erc-nicks--highlight nick face)))
-    (setf (erc-button--nick-nickname-face nick-object) out))
+    (setf (erc-button--nick-nickname-face nick-object) out
+          ;;
+          (erc-button--nick-face-cache nick-object)
+          (and erc-nicks-track-faces
+               (bound-and-true-p erc-track--normal-faces)
+               #'erc-nicks--remember-face-for-track)))
   nick-object)
 
 (define-erc-module nicks nil
@@ -559,6 +568,9 @@ nicks
        erc-nicks--face-table (make-hash-table :test #'equal)))
    (setf (alist-get "Edit face" erc-button--nick-popup-alist nil nil #'equal)
          #'erc-nicks-customize-face)
+   (unless erc-nicks-track-faces
+     (erc-nicks--setup-track-integration)
+     (add-hook 'erc-track-mode #'erc-nicks--setup-track-integration 50 t))
    (advice-add 'widget-create-child-and-convert :filter-args
                #'erc-nicks--redirect-face-widget-link))
   ((kill-local-variable 'erc-nicks--face-table)
@@ -570,6 +582,8 @@ nicks
    (kill-local-variable 'erc-nicks--downcased-skip-nicks)
    (when (fboundp 'erc-button--phantom-users-mode)
      (erc-button--phantom-users-mode -1))
+   (remove-function (local 'erc-track--face-reject-function)
+                    #'erc-nicks--reject-uninterned-faces)
    (remove-function (local 'erc-button--modify-nick-function)
                     #'erc-nicks--highlight-button)
    (setf (alist-get "Edit face"
@@ -691,6 +705,32 @@ erc-nicks--colors-from-faces
                  (color (face-foreground face)))
         (push color out)))))
 
+(defun erc-nicks--reject-uninterned-faces (candidate)
+  "Remove own faces from CANDIDATE if it's a combination of faces."
+  (while-let ((next (car-safe candidate))
+              ((facep next))
+              ((not (intern-soft next))))
+    (setq candidate (cdr candidate)))
+  (if (and (consp candidate) (not (cdr candidate))) (car candidate) candidate))
+
+(defun erc-nicks--setup-track-integration ()
+  "Restore traditional \"alternating normal\" face functionality to mode-line."
+  (cl-assert (not erc-nicks-track-faces))
+  (when (bound-and-true-p erc-track-mode)
+    (add-function :override (local 'erc-track--face-reject-function)
+                  #'erc-nicks--reject-uninterned-faces)))
+
+(defun erc-nicks--remember-face-for-track (face)
+  "Add FACE to local hash table maintained by `track' module."
+  (defvar erc-track--normal-faces)
+  (cl-assert erc-track--normal-faces)
+  (or (gethash face erc-track--normal-faces)
+      (if-let ((sym (or (car-safe face) face))
+               ((symbolp sym))
+               ((get sym 'erc-nicks--key)))
+          (puthash face face erc-track--normal-faces)
+        face)))
+
 (provide 'erc-nicks)
 
 ;;; erc-nicks.el ends here
diff --git a/lisp/erc/erc.el b/lisp/erc/erc.el
index 62fdc0ad6e8..2734c602fa2 100644
--- a/lisp/erc/erc.el
+++ b/lisp/erc/erc.el
@@ -3351,12 +3351,14 @@ erc--merge-text-properties-p
 ;; values and optionally dispense archetypal constants in their place
 ;; in order to ensure all occurrences of some list (a b) across all
 ;; text-properties in all ERC buffers are actually the same object.
-(defun erc--merge-prop (from to prop val &optional object)
+(defun erc--merge-prop (from to prop val &optional object cache-fn)
   "Combine existing PROP values with VAL between FROM and TO in OBJECT.
 For spans where PROP is non-nil, cons VAL onto the existing
 value, ensuring a proper list.  Otherwise, just set PROP to VAL.
 When VAL is itself a list, prepend its members onto an existing
-value.  See also `erc-button-add-face'."
+value.  Call CACHE-FN, when given, with the new value for prop.
+It must return a suitable replacement or the same value.  See
+also `erc-button-add-face'."
   (let ((old (get-text-property from prop object))
         (pos from)
         (end (next-single-property-change from prop object to))
@@ -3370,6 +3372,8 @@ erc--merge-prop
                           (append val (ensure-list old))
                         (cons val (ensure-list old))))
                   val))
+      (when cache-fn
+        (setq new (funcall cache-fn new)))
       (put-text-property pos end prop new object)
       (setq pos end
             old (get-text-property pos prop object)
-- 
2.42.0


^ permalink raw reply related	[flat|nested] 9+ messages in thread

* bug#67767: 30.0.50; ERC 5.6: Add track integration to the nicks module
  2023-12-11 15:28 bug#67767: 30.0.50; ERC 5.6: Add track integration to the nicks module J.P.
  2023-12-12  2:18 ` J.P.
  2023-12-12 14:49 ` J.P.
@ 2023-12-13 14:06 ` J.P.
       [not found] ` <8734w6yz76.fsf@neverwas.me>
                   ` (2 subsequent siblings)
  5 siblings, 0 replies; 9+ messages in thread
From: J.P. @ 2023-12-13 14:06 UTC (permalink / raw)
  To: 67767; +Cc: emacs-erc

[-- Attachment #1: Type: text/plain, Size: 206 bytes --]

v3. Make default behavior of `erc-nicks-track-faces' more intuitive. Fix
issue with detection of obsolete button face in `track' options. Make
`erc-track--select-mode-line-face' more convenient to modify.


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From e14973511bf0c845ceaac2121c95cc47c6b17ae5 Mon Sep 17 00:00:00 2001
From: "F. Jason Park" <jp@neverwas.me>
Date: Wed, 13 Dec 2023 00:00:42 -0800
Subject: [PATCH 0/5] *** NOT A PATCH ***

*** BLURB HERE ***

F. Jason Park (5):
  [5.6] Include rather than combine erc-nicks-backing-face
  [5.6] Fix Custom :type of erc-track-faces-normal-list
  [5.7] Promote "normal" faces in erc-track
  [5.7] Cache shortened channel names in erc-track
  [5.7] Add erc-track integration to erc-nicks

 etc/ERC-NEWS                     |  39 +++++
 lisp/erc/erc-button.el           |  49 +++---
 lisp/erc/erc-nicks.el            |  95 ++++++++++-
 lisp/erc/erc-track.el            | 270 +++++++++++++++++++++++++++----
 lisp/erc/erc.el                  |   8 +-
 test/lisp/erc/erc-nicks-tests.el |   2 +-
 test/lisp/erc/erc-track-tests.el | 166 +++++++++++++++++++
 7 files changed, 570 insertions(+), 59 deletions(-)

Interdiff:
diff --git a/lisp/erc/erc-nicks.el b/lisp/erc/erc-nicks.el
index 92dd03912e6..0b1e5e0c050 100644
--- a/lisp/erc/erc-nicks.el
+++ b/lisp/erc/erc-nicks.el
@@ -173,9 +173,19 @@ erc-nicks-key-suffix-format
 like \"@%-012n\"."
   :type 'string)
 
-(defcustom erc-nicks-track-faces t
-  "Show nick faces in the `track' module's portion of the mode line."
-  :type 'boolean)
+(defcustom erc-nicks-track-faces 'prioritize
+  "Show nick faces in the `track' module's portion of the mode line.
+A value of nil means don't show nick faces at all.  A value of
+`defer' means have `track' consider nick faces only after those
+ranked faces in `erc-track-faces-normal-list'.  This has the
+effect of \"alternating\" between a ranked \"normal\" and a nick.
+The value `prioritize' means have `track' consider nick faces to
+be \"normal\" unless the current speaker is the same as the
+previous one, in which case pretend the value is `defer'.  Like
+most options in this module, updating the value mid-session is
+not officially supported, although cycling \\[erc-nicks-mode] may
+be worth a shot."
+  :type '(choice (const nil) (const defer) (const prioritize)))
 
 (defvar erc-nicks--max-skip-search 3 ; make this an option?
   "Max number of faces to visit when testing `erc-nicks-skip-faces'.")
@@ -568,9 +578,8 @@ nicks
        erc-nicks--face-table (make-hash-table :test #'equal)))
    (setf (alist-get "Edit face" erc-button--nick-popup-alist nil nil #'equal)
          #'erc-nicks-customize-face)
-   (unless erc-nicks-track-faces
-     (erc-nicks--setup-track-integration)
-     (add-hook 'erc-track-mode #'erc-nicks--setup-track-integration 50 t))
+   (erc-nicks--setup-track-integration)
+   (add-hook 'erc-track-mode #'erc-nicks--setup-track-integration 50 t)
    (advice-add 'widget-create-child-and-convert :filter-args
                #'erc-nicks--redirect-face-widget-link))
   ((kill-local-variable 'erc-nicks--face-table)
@@ -586,6 +595,8 @@ nicks
                     #'erc-nicks--reject-uninterned-faces)
    (remove-function (local 'erc-button--modify-nick-function)
                     #'erc-nicks--highlight-button)
+   (remove-function (local 'erc-track--alt-normals-function)
+                    #'erc-nicks--check-normals)
    (setf (alist-get "Edit face"
                     erc-button--nick-popup-alist nil 'remove #'equal)
          nil)
@@ -713,12 +724,42 @@ erc-nicks--reject-uninterned-faces
     (setq candidate (cdr candidate)))
   (if (and (consp candidate) (not (cdr candidate))) (car candidate) candidate))
 
+(define-inline erc-nicks--oursp (face)
+  (inline-quote
+   (and-let* ((sym (car-safe ,face))
+              ((symbolp sym))
+              ((get sym 'erc-nicks--key)))
+     sym)))
+
+(defun erc-nicks--check-normals (current contender contenders normals)
+  "Return a viable `nicks'-owned face from NORMALS in CONTENDERS.
+But only do so if the CURRENT face is also one of ours and in
+NORMALS and if the highest ranked CONTENDER among new faces is
+`erc-default-face', the lowest ranking default priority face."
+  (defvar erc-track--normal-faces)
+  (cl-assert erc-track--normal-faces)
+  (and-let* (((eq contender 'erc-default-face))
+             ((gethash current normals))
+             (spkr (erc-nicks--oursp current)))
+    (catch 'contender
+      (dolist (candidate (cdr contenders) contender)
+        (when-let (((not (equal candidate current)))
+                   ((gethash candidate normals))
+                   (s (erc-nicks--oursp candidate))
+                   ((not (eq s spkr))))
+          (throw 'contender candidate))))))
+
 (defun erc-nicks--setup-track-integration ()
   "Restore traditional \"alternating normal\" face functionality to mode-line."
-  (cl-assert (not erc-nicks-track-faces))
   (when (bound-and-true-p erc-track-mode)
-    (add-function :override (local 'erc-track--face-reject-function)
-                  #'erc-nicks--reject-uninterned-faces)))
+    (pcase erc-nicks-track-faces
+      ;; Variant `defer' is handled elsewhere.
+      ('prioritize
+       (add-function :override (local 'erc-track--alt-normals-function)
+                     #'erc-nicks--check-normals))
+      ('nil
+       (add-function :override (local 'erc-track--face-reject-function)
+                     #'erc-nicks--reject-uninterned-faces)))))
 
 (defun erc-nicks--remember-face-for-track (face)
   "Add FACE to local hash table maintained by `track' module."
diff --git a/lisp/erc/erc-track.el b/lisp/erc/erc-track.el
index 4c3c7ca49a5..a6a1539b044 100644
--- a/lisp/erc/erc-track.el
+++ b/lisp/erc/erc-track.el
@@ -166,20 +166,25 @@ erc-track-use-faces
 ;; (erc-nick-default-face erc-pal-face).  However, since at least
 ;; Emacs 27, `match' has done its damage after `button' in
 ;; `erc-insert-modify-hook', meaning such permutations cannot exist.
-(defvar erc-track--old-nick-button-faces
-  '((erc-nick-default-face erc-default-face))
-  "List of obsolete nick button faces.")
-
-(defun erc-track--massage-nick-button-faces (val)
-  "Update members of face list VAL to have the default nick button face.
-In ERC 5.7, it changed from `erc-current-nick-face' to
-`erc-button-nick-default-face'."
-  (mapcar (lambda (f)
-            (if (and (eq (car-safe f) 'erc-nick-default-face)
-                     (member f erc-track--old-nick-button-faces))
-                (cons 'erc-button-nick-default-face (cdr f))
-              f))
-          val))
+(defun erc-track--massage-nick-button-faces (sym val &optional set-fn)
+  "Transform VAL of face-list option SYM to have new defaults.
+Use `set'-compatible SET-FN when given.  If an update was
+performed, stash a copy of the replaced VAL member in the symbol
+property `erc-track--obsolete-faces' of SYM."
+  (let* ((changedp nil)
+         (new (mapcar
+               (lambda (f)
+                 (if (and (eq (car-safe f) 'erc-nick-default-face)
+                          (equal f '(erc-nick-default-face erc-default-face)))
+                     (progn
+                       (setq changedp t)
+                       (put sym 'erc-track--obsolete-faces t)
+                       (cons 'erc-button-nick-default-face (cdr f)))
+                   f))
+               val)))
+    (if set-fn
+        (funcall set-fn sym (if changedp new val))
+      (set-default sym (if changedp new val)))))
 
 (defcustom erc-track-faces-priority-list
   '(erc-error-face
@@ -205,8 +210,7 @@ erc-track-faces-priority-list
 Note that ERC prioritizes certain faces reserved for critical
 messages regardless of this option's value."
   :package-version '(ERC . "5.7") ; FIXME sync on release
-  :set (lambda (sym val)
-         (set-default sym (erc-track--massage-nick-button-faces val)))
+  :set #'erc-track--massage-nick-button-faces
   :type (erc--with-dependent-type-match
          (repeat (choice face (repeat :tag "Combination" face)))
          erc-button))
@@ -248,10 +252,10 @@ erc-track-faces-normal-list
 
 The effect may be disabled by setting this variable to nil."
   :package-version '(ERC . "5.7") ; FIXME sync on release
-  :set (lambda (sym val)
-         (set-default sym (erc-track--massage-nick-button-faces val)))
-  :type '(repeat (choice face
-			 (repeat :tag "Combination" face))))
+  :set #'erc-track--massage-nick-button-faces
+  :type (erc--with-dependent-type-match
+         (repeat (choice face (repeat :tag "Combination" face)))
+         erc-button))
 
 (defvar erc-track-ignore-normal-contenders-p nil
   "Compatibility flag to promote only exclusively new \"normal\" faces.
@@ -649,30 +653,29 @@ erc-track--setup
       (let ((existing (erc-with-server-buffer erc-track--normal-faces))
             (localp (and erc--target
                          (local-variable-p 'erc-track-faces-normal-list)))
+            (opts '(erc-track-faces-normal-list erc-track-faces-priority-list))
             warnp table)
+        ;; Don't bother warning users who've disabled `button'.
         (unless (or erc--target (not (or (bound-and-true-p erc-button-mode)
                                          (memq 'button erc-modules))))
-          (dolist (opt '(erc-track-faces-normal-list
-                         erc-track-faces-priority-list))
-            (when (seq-some
-                   (lambda (f)
-                     (and (eq (car-safe f) 'erc-nick-default-face)
-                          (member f erc-track--old-nick-button-faces)))
-                   (symbol-value opt))
+          (when (or localp (local-variable-p 'erc-track-faces-priority-list))
+            (dolist (opt opts)
+              (erc-track--massage-nick-button-faces opt (symbol-value opt)
+                                                    #'set)))
+          (dolist (opt opts)
+            (when (get opt 'erc-track--obsolete-faces)
               (push opt warnp)
-              (set opt (erc-track--massage-nick-button-faces
-                        (symbol-value opt)))))
+              (put opt 'erc-track--obsolete-faces nil)))
           (when warnp
             (erc--warn-once-before-connect 'erc-track-mode
               (if (cdr warnp) "Options " "Option ")
               (mapconcat (lambda (o) (format "`%S'" o)) warnp " and ")
               (if (cdr warnp) " contain" " contains")
-              " obsolete list-style faces intended to match buttonized"
-              " nicknames. To silence this warning, please update members"
-              " with `%S' at their head, like %S, by converting them to %S."
-              " ERC has done this for you for this session."
-              'erc-nick-default-face '(erc-nick-default-face foo)
-              '(erc-button-nick-default-face foo))))
+              " an obsolete item, %S, intended to match buttonized nicknames."
+              " ERC has changed it to %S for the current session."
+              " Please save the current value to silence this message."
+              '(erc-nick-default-face erc-default-face)
+              '(erc-button-nick-default-face erc-default-face))))
         (when (or (null existing) localp)
           (setq table (map-into (mapcar (lambda (f) (cons f f))
                                         erc-track-faces-normal-list)
@@ -913,12 +916,12 @@ erc-track-select-mode-line-face
               choice))
         choice))))
 
-(define-inline erc-track--gett (table-or-function key)
-  "Look up KEY via TABLE-OR-FUNCTION."
-  (inline-quote
-   (if (functionp ,table-or-function)
-       (funcall ,table-or-function ,key)
-     (gethash ,key ,table-or-function))))
+(defvar erc-track--alt-normals-function nil
+  "A function to possibly elect a \"normal\" face.
+Called with the current incumbent and the worthiest new contender
+followed by all new contending faces and so-called \"normal\"
+faces.  See `erc-track--select-mode-line-face' for their meanings
+and expected types.  This function should return a face or nil.")
 
 (defun erc-track--select-mode-line-face (cur-face new-faces ranks normals)
   "Return CUR-FACE or a replacement for displaying in the mode-line, or nil.
@@ -929,12 +932,12 @@ erc-track--select-mode-line-face
 If NEW-FACES has a cdr, expect it to be its car's contents
 ordered from most recently seen (later in the buffer) to
 earliest.  In general, act like `erc-track-select-mode-line-face'
-except reconsider NEW-FACES when CUR-FACE outranks all its
-members.  That is, choose the highest RANKS among NEW-FACES not
-equal to CUR-FACE.  Failing that, choose the first face in
-NORMALS to appear anywhere in NEW-FACES, but only if NEW-FACES
-has a cdr.  If NORMALS is a function, call it with the name of a
-face to query membership."
+except appeal to `erc-track--alt-normals-function' if it's
+non-nil, falling back on reconsidering NEW-FACES when CUR-FACE
+outranks all its members.  That is, choose the first among RANKS
+in NEW-FACES not equal to CUR-FACE.  Failing that, choose the
+first face in NEW-FACES that's also in NORMALS, assuming
+NEW-FACES has a cdr."
   (cl-check-type erc-track-ignore-normal-contenders-p null)
   (cl-check-type new-faces cons)
   (when-let ((choice (catch 'face
@@ -942,21 +945,23 @@ erc-track--select-mode-line-face
                          (when (or (equal candidate cur-face)
                                    (gethash candidate (car new-faces)))
                            (throw 'face candidate))))))
-    (when-let (((equal choice cur-face))
-               ((erc-track--gett normals choice))
-               (contender (catch 'face
-                            (progn
-                              (dolist (candidate ranks)
-                                (when (and (not (equal candidate choice))
-                                           (gethash candidate (car new-faces))
-                                           (erc-track--gett normals candidate))
-                                  (throw 'face candidate)))
-                              (dolist (f (cdr new-faces))
-                                (when (and (not (equal f choice))
-                                           (erc-track--gett normals f))
-                                  (throw 'face f)))))))
-      (setq choice contender))
-    choice))
+    (or (and erc-track--alt-normals-function
+             (funcall erc-track--alt-normals-function
+                      cur-face choice new-faces normals))
+        (and (equal choice cur-face)
+             (gethash choice normals)
+             (catch 'face
+               (progn
+                 (dolist (candidate ranks)
+                   (when (and (not (equal candidate choice))
+                              (gethash candidate (car new-faces))
+                              (gethash choice normals))
+                     (throw 'face candidate)))
+                 (dolist (candidate (cdr new-faces))
+                   (when (and (not (equal candidate choice))
+                              (gethash candidate normals))
+                     (throw 'face candidate))))))
+        choice)))
 
 (defvar erc-track--skipped-msgs '(datestamp)
   "Values of `erc-msg' text prop to ignore.")
-- 
2.42.0


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From 8f3926d0dd13a430bf4d8492e0e418e9677c8091 Mon Sep 17 00:00:00 2001
From: "F. Jason Park" <jp@neverwas.me>
Date: Mon, 11 Dec 2023 20:24:17 -0800
Subject: [PATCH 1/5] [5.6] Include rather than combine erc-nicks-backing-face

* lisp/erc/erc-nicks.el (erc-nicks--get-face): Make generated face
:inherit from `erc-nicks-backing-face'.
(erc-nicks--highlight): Just return the generated face instead of
combining it with `erc-nicks-backing-face' or the existing face in the
buffer.
* test/lisp/erc/erc-nicks-tests.el (erc-nicks-list-faces): Skip
"Inherit: " button.
---
 lisp/erc/erc-nicks.el            | 12 +++++-------
 test/lisp/erc/erc-nicks-tests.el |  2 +-
 2 files changed, 6 insertions(+), 8 deletions(-)

diff --git a/lisp/erc/erc-nicks.el b/lisp/erc/erc-nicks.el
index fcd3afdbbc4..2f0c3261266 100644
--- a/lisp/erc/erc-nicks.el
+++ b/lisp/erc/erc-nicks.el
@@ -454,7 +454,9 @@ erc-nicks--get-face
           (put new-face 'erc-nicks--nick nick)
           (put new-face 'erc-nicks--netid erc-networks--id)
           (put new-face 'erc-nicks--key key)
-          (face-spec-set new-face `((t :foreground ,color)) 'face-defface-spec)
+          (face-spec-set new-face `((t :foreground ,color
+                                       :inherit ,erc-nicks-backing-face))
+                         'face-defface-spec)
           (set-face-documentation
            new-face (format "Internal face for %s on %s." nick (erc-network)))
           (puthash nick new-face table)))))
@@ -503,12 +505,8 @@ erc-nicks--highlight
              ((not (and base-face
                         (erc-nicks--skip-p base-face erc-nicks-skip-faces
                                            erc-nicks--max-skip-search))))
-             (key (erc-nicks--gen-key-from-format-spec trimmed))
-             (out (erc-nicks--get-face trimmed key)))
-    (if (or (null erc-nicks-backing-face)
-            (eq base-face erc-nicks-backing-face))
-        out
-      (cons out (erc-list erc-nicks-backing-face)))))
+             (key (erc-nicks--gen-key-from-format-spec trimmed)))
+    (erc-nicks--get-face trimmed key)))
 
 (defun erc-nicks--highlight-button (nick-object)
   "Possibly add face to `erc-button--nick-user' NICK-OBJECT."
diff --git a/test/lisp/erc/erc-nicks-tests.el b/test/lisp/erc/erc-nicks-tests.el
index 35264a23caa..54882278139 100644
--- a/test/lisp/erc/erc-nicks-tests.el
+++ b/test/lisp/erc/erc-nicks-tests.el
@@ -409,7 +409,7 @@ erc-nicks-list-faces
              (push-button)
              (should (search-forward-regexp
                       (rx "Foreground: #" (group (+ xdigit)) eol)))
-             (forward-button 1)
+             (forward-button 2) ; skip Inherit:...
              (push-button))
 
            (ert-info ("First entry's sample is rendered correctly")
-- 
2.42.0


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From be105b8d876c4e0bace6049726302bde1cae7cdd Mon Sep 17 00:00:00 2001
From: "F. Jason Park" <jp@neverwas.me>
Date: Tue, 12 Dec 2023 19:04:12 -0800
Subject: [PATCH 2/5] [5.6] Fix Custom :type of erc-track-faces-normal-list

* lisp/erc/erc-track.el (erc-modified-channels-object):
Load `erc-button' during validation so that Customize chooses the
correct UI instead of a generic field with "(mismatch)" printed
alongside the "STATE" button.
---
 lisp/erc/erc-track.el | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/lisp/erc/erc-track.el b/lisp/erc/erc-track.el
index a36b781e04d..db10063cafe 100644
--- a/lisp/erc/erc-track.el
+++ b/lisp/erc/erc-track.el
@@ -225,8 +225,9 @@ erc-track-faces-normal-list
 are occurring in these channels.
 
 The effect may be disabled by setting this variable to nil."
-  :type '(repeat (choice face
-			 (repeat :tag "Combination" face))))
+  :type (erc--with-dependent-type-match
+         (repeat (choice face (repeat :tag "Combination" face)))
+         erc-button))
 
 (defcustom erc-track-position-in-mode-line 'before-modes
   "Where to show modified channel information in the mode-line.
-- 
2.42.0


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From 60e297cf14c873bd55a73e80bb77c71a78f6a5e3 Mon Sep 17 00:00:00 2001
From: "F. Jason Park" <jp@neverwas.me>
Date: Sun, 10 Dec 2023 05:33:48 -0800
Subject: [PATCH 3/5] [5.7] Promote "normal" faces in erc-track

* etc/ERC-NEWS: Add entry for new behavior involving the option
`erc-track-faces-normal-list'.
* lisp/erc/erc-button.el (erc-button-nick-default-face): New face to
serve as default for `erc-button-nickname-face'.
(erc-button-nickname-face): Change default value to
`erc-button-nick-default-face'.
* lisp/erc/erc-track.el (erc-track--massage-nick-button-faces): New
function to serve as Custom :set function for priority and "normal"
face-list options.
(erc-track-faces-priority-list, erc-track-faces-normal-list): Change
values for `match' module faces to feature
`erc-button-nick-default-face' instead of `erc-nick-default-face'.
Use :set function to massage saved user values.
(erc-track-ignore-normal-contenders-p): New compatibility switch to
access pre-5.6 behavior, in which faces in
`erc-track-faces-normal-list' were only considered for promotion to
the mode line if the current face occupying that pole position wasn't
present.
(erc-track-mode, erc-track-enable, erc-track-disable): Add FIXME
comments regarding perceived futility of `erc-server-001-functions and
likely unneeded hook removal.  Run common buffer-local setup and
teardown.
(erc-track--normal-faces): New local variable, a snapshot of
`erc-track-faces-normal-list'.
(erc-track--setup): New function to stash
`erc-track-faces-normal-list' on init.
(erc-track-select-mode-line-face): Offer alternate explanation of
certain particulars in doc string.
(erc-track--alt-normals-function): New function-valued variable to
allow other modules to intervene in deciding whether to pursue and
promote a "normal" contending face.
(erc-track--select-mode-line-face): New function similar to its public
namesake except that it considers other viable candidates among the
"normal" alternatives.
(erc-track-modified-channels): Only run face selection portion when
faces are actually found.  Use `erc-track--select-mode-line-face'
instead of `erc-track-select-mode-line-face'.
* test/lisp/erc/erc-track-tests.el
(erc-track-select-mode-line-face): New test.
(erc-track-tests--select-mode-line-face): New function.
(erc-track--select-mode-line-face): New test.  (Bug#67767)
---
 etc/ERC-NEWS                     |  39 ++++++
 lisp/erc/erc-button.el           |   8 +-
 lisp/erc/erc-track.el            | 223 ++++++++++++++++++++++++++++---
 test/lisp/erc/erc-track-tests.el | 130 ++++++++++++++++++
 4 files changed, 377 insertions(+), 23 deletions(-)

diff --git a/etc/ERC-NEWS b/etc/ERC-NEWS
index 4642c742b0f..40e3d5d5638 100644
--- a/etc/ERC-NEWS
+++ b/etc/ERC-NEWS
@@ -170,6 +170,19 @@ options, like 'erc-command-indicator', have moved to the 'erc-goodies'
 library, although their Custom groups remain the same.  Add
 'command-indicator' to 'erc-modules' to get started.
 
+** Option 'erc-track-faces-normal-list' slightly more influential.
+This option has always been a source of confusion for users, mainly
+because its influence rode heavily on the makeup of faces in a given
+message.  Historically, when a buffer's current mode-line face was a
+member of this option's value, ERC would only swap it out for a fellow
+"normal" if it was absent from message being processed.  Beginning
+with this release, ERC now looks to other ranked and (if necessary)
+unranked "normals" instead of sustaining the same face between
+messages.  This was done to better honor the stated purpose of the
+option, which is to provide consistent visual feedback when buffer
+activity occurs.  If you experience problems with this development,
+see the compatibility flag 'erc-track-ignore-normal-contenders-p'.
+
 ** 'erc-button-alist' and 'erc-nick-popup-alist' have evolved slightly.
 It's no secret that the 'buttons' module treats potential nicknames
 specially.  This is perhaps most evident in its treatment of the
@@ -184,6 +197,23 @@ s-expressions, which ERC will continue to honor.  Although the default
 lineup remains functionally equivalent, its members have all been
 updated accordingly.
 
+** 'erc-track-faces-priority-list' and 'erc-track-faces-normal-list' slimmed.
+These options have been purged of certain 'button'-related face
+combinations.  Originally added in ERC 5.3, these combinations
+described the effect of "buttonizing" atop faces added by the 'match'
+module, like '(erc-nick-default-face erc-pal-face)'.  However, since
+at least Emacs 27, 'match' has run before 'button' in
+'erc-insert-modify-hook', meaning such permutations aren't possible.
+
+More importantly, users who've customized either of these options
+should update them with the new default value of the option
+'erc-button-nickname-face'.  Like 'erc-nick-default-face', which it
+replaces, the new 'erc-button-nick-default-face' is also a "real"
+face.  Its sole reason for existing is to make it easier for users and
+modules to distinguish between basic buttonized faces and
+'erc-nick-default-face', which is now reserved to mean the base
+"speaker" face.
+
 ** Option 'erc-query-on-unjoined-chan-privmsg' restored and renamed.
 This option was accidentally removed from the default client in ERC
 5.5 and was thus prevented from influencing PRIVMSG routing.  It's now
@@ -306,6 +336,15 @@ from 't' to the more useful 'erc-prompt', although the property of the
 same name has been retained and now has a value of 'hidden' when
 disconnected.
 
+*** Lists of faces in buttonized text are no longer nested.
+Previously, when "buttonizing" a new region, ERC would combine faces
+by blindly consing the new onto the existing.  In theory, this kept a
+nice record of all modifications to a given region.  However, it also
+complicated life for other modules wanting to analyze and operate on
+these regions.  Beginning with this release, ERC now merges combined
+faces together when creating buttons, although the odd nested list may
+still crop up here and there.
+
 *** Members of insert- and send-related hooks have been reordered.
 As anyone reading this is no doubt aware, both built-in and
 third-party modules rely on certain hooks for adjusting incoming and
diff --git a/lisp/erc/erc-button.el b/lisp/erc/erc-button.el
index e1c10be53f6..f10d7a2fce7 100644
--- a/lisp/erc/erc-button.el
+++ b/lisp/erc/erc-button.el
@@ -70,6 +70,11 @@ erc-button
   "ERC button face."
   :group 'erc-faces)
 
+(defface erc-button-nick-default-face '((t :inherit erc-nick-default-face))
+  "Default face for a buttonized nickname."
+  :package-version '(ERC . "5.7") ; FIXME sync on release
+  :group 'erc-faces)
+
 (defcustom erc-button-face 'erc-button
   "Face used for highlighting buttons in ERC buffers.
 
@@ -78,8 +83,9 @@ erc-button-face
   :type 'face
   :group 'erc-faces)
 
-(defcustom erc-button-nickname-face 'erc-nick-default-face
+(defcustom erc-button-nickname-face 'erc-button-nick-default-face
   "Face used for ERC nickname buttons."
+  :package-version '(ERC . "5.7") ; FIXME sync on release
   :type 'face
   :group 'erc-faces)
 
diff --git a/lisp/erc/erc-track.el b/lisp/erc/erc-track.el
index db10063cafe..490fc52d42c 100644
--- a/lisp/erc/erc-track.el
+++ b/lisp/erc/erc-track.el
@@ -161,23 +161,44 @@ erc-track-use-faces
 \(e.g. `erc-pal-face' is used if a pal sent a message to that channel.)"
   :type 'boolean)
 
+;; Historically, `erc-track-faces-priority-list' had members
+;; describing the effect of buttonizing atop faces from `match', e.g.,
+;; (erc-nick-default-face erc-pal-face).  However, since at least
+;; Emacs 27, `match' has done its damage after `button' in
+;; `erc-insert-modify-hook', meaning such permutations cannot exist.
+(defun erc-track--massage-nick-button-faces (sym val &optional set-fn)
+  "Transform VAL of face-list option SYM to have new defaults.
+Use `set'-compatible SET-FN when given.  If an update was
+performed, stash a copy of the replaced VAL member in the symbol
+property `erc-track--obsolete-faces' of SYM."
+  (let* ((changedp nil)
+         (new (mapcar
+               (lambda (f)
+                 (if (and (eq (car-safe f) 'erc-nick-default-face)
+                          (equal f '(erc-nick-default-face erc-default-face)))
+                     (progn
+                       (setq changedp t)
+                       (put sym 'erc-track--obsolete-faces t)
+                       (cons 'erc-button-nick-default-face (cdr f)))
+                   f))
+               val)))
+    (if set-fn
+        (funcall set-fn sym (if changedp new val))
+      (set-default sym (if changedp new val)))))
+
 (defcustom erc-track-faces-priority-list
   '(erc-error-face
-    (erc-nick-default-face erc-current-nick-face)
     erc-current-nick-face
     erc-keyword-face
-    (erc-nick-default-face erc-pal-face)
     erc-pal-face
     erc-nick-msg-face
     erc-direct-msg-face
     (erc-button erc-default-face)
-    (erc-nick-default-face erc-dangerous-host-face)
     erc-dangerous-host-face
     erc-nick-default-face
-    (erc-nick-default-face erc-default-face)
+    (erc-button-nick-default-face erc-default-face)
     erc-default-face
     erc-action-face
-    (erc-nick-default-face erc-fool-face)
     erc-fool-face
     erc-notice-face
     erc-input-face
@@ -188,6 +209,8 @@ erc-track-faces-priority-list
 
 Note that ERC prioritizes certain faces reserved for critical
 messages regardless of this option's value."
+  :package-version '(ERC . "5.7") ; FIXME sync on release
+  :set #'erc-track--massage-nick-button-faces
   :type (erc--with-dependent-type-match
          (repeat (choice face (repeat :tag "Combination" face)))
          erc-button))
@@ -209,10 +232,9 @@ erc-track-priority-faces-only
 
 (defcustom erc-track-faces-normal-list
   '((erc-button erc-default-face)
-    (erc-nick-default-face erc-dangerous-host-face)
     erc-dangerous-host-face
     erc-nick-default-face
-    (erc-nick-default-face erc-default-face)
+    (erc-button-nick-default-face erc-default-face)
     erc-default-face
     erc-action-face)
   "A list of faces considered to be part of normal conversations.
@@ -224,11 +246,26 @@ erc-track-faces-normal-list
 message.  This gives a rough indication that active conversations
 are occurring in these channels.
 
+Note that ERC makes a copy of this option when initializing the
+module.  To see your changes reflected mid-session, cycle
+\\[erc-track-mode].
+
 The effect may be disabled by setting this variable to nil."
+  :package-version '(ERC . "5.7") ; FIXME sync on release
+  :set #'erc-track--massage-nick-button-faces
   :type (erc--with-dependent-type-match
          (repeat (choice face (repeat :tag "Combination" face)))
          erc-button))
 
+(defvar erc-track-ignore-normal-contenders-p nil
+  "Compatibility flag to promote only exclusively new \"normal\" faces.
+When non-nil, revert to pre-5.6 behavior in which a current
+mode-line face that both outranks and is absent from the current
+message is eligible for replacement with a fellow face from
+`erc-track-faces-normal-list' that does appear in the message.
+By extension, when enabled, never replace the current, reigning
+mode-line face if it's present in the current message.")
+
 (defcustom erc-track-position-in-mode-line 'before-modes
   "Where to show modified channel information in the mode-line.
 
@@ -519,6 +556,9 @@ track
 	 (progn
 	   (add-hook 'window-configuration-change-hook #'erc-user-is-active)
 	   (add-hook 'erc-send-completed-hook #'erc-user-is-active)
+           ;; FIXME find out why this uses `erc-server-001-functions'.
+           ;; `erc-user-is-active' runs when `erc-server-connected' is
+           ;; non-nil.  But this hook usually only runs when it's nil.
 	   (add-hook 'erc-server-001-functions #'erc-user-is-active))
        (erc-track-add-to-mode-line erc-track-position-in-mode-line)
        (erc-update-mode-line)
@@ -529,6 +569,8 @@ track
      ;; enable the tracking keybindings
      (add-hook 'erc-connect-pre-hook #'erc-track-minor-mode-maybe)
      (erc-track-minor-mode-maybe))
+   (add-hook 'erc-mode-hook #'erc-track--setup)
+   (unless erc--updating-modules-p (erc-buffer-do #'erc-track--setup))
    (add-hook 'erc-networks--copy-server-buffer-functions
              #'erc-track--replace-killed-buffer))
   ;; Disable:
@@ -540,6 +582,7 @@ track
 			#'erc-user-is-active)
 	   (remove-hook 'erc-send-completed-hook #'erc-user-is-active)
 	   (remove-hook 'erc-server-001-functions #'erc-user-is-active)
+           ;; FIXME remove this if unused.
 	   (remove-hook 'erc-timer-hook #'erc-user-is-active))
        (remove-hook 'window-configuration-change-hook
 		    #'erc-window-configuration-change)
@@ -549,9 +592,12 @@ track
      (remove-hook 'erc-connect-pre-hook #'erc-track-minor-mode-maybe)
      (when erc-track-minor-mode
        (erc-track-minor-mode -1)))
+   (remove-hook 'erc-mode-hook #'erc-track--setup)
+   (erc-buffer-do #'erc-track--setup)
    (remove-hook 'erc-networks--copy-server-buffer-functions
                 #'erc-track--replace-killed-buffer)))
 
+;; FIXME move this above the module definition.
 (defcustom erc-track-when-inactive nil
   "Enable channel tracking even for visible buffers, if you are inactive."
   :type 'boolean
@@ -563,6 +609,51 @@ erc-track-when-inactive
 	       (erc-track-enable))
 	   (set sym val))))
 
+(defvar-local erc-track--normal-faces nil
+  "Local copy of `erc-track-faces-normal-list' as a hash table.")
+
+(defun erc-track--setup ()
+  "Initialize a buffer for use with the `track' module.
+If this is a server buffer or `erc-track-faces-normal-list' is
+locally bound, create a new `erc-track--normal-faces' for the
+current buffer.  Otherwise, set the local value to the server
+buffer's."
+  (if erc-track-mode
+      (let ((existing (erc-with-server-buffer erc-track--normal-faces))
+            (localp (and erc--target
+                         (local-variable-p 'erc-track-faces-normal-list)))
+            (opts '(erc-track-faces-normal-list erc-track-faces-priority-list))
+            warnp table)
+        ;; Don't bother warning users who've disabled `button'.
+        (unless (or erc--target (not (or (bound-and-true-p erc-button-mode)
+                                         (memq 'button erc-modules))))
+          (when (or localp (local-variable-p 'erc-track-faces-priority-list))
+            (dolist (opt opts)
+              (erc-track--massage-nick-button-faces opt (symbol-value opt)
+                                                    #'set)))
+          (dolist (opt opts)
+            (when (get opt 'erc-track--obsolete-faces)
+              (push opt warnp)
+              (put opt 'erc-track--obsolete-faces nil)))
+          (when warnp
+            (erc--warn-once-before-connect 'erc-track-mode
+              (if (cdr warnp) "Options " "Option ")
+              (mapconcat (lambda (o) (format "`%S'" o)) warnp " and ")
+              (if (cdr warnp) " contain" " contains")
+              " an obsolete item, %S, intended to match buttonized nicknames."
+              " ERC has changed it to %S for the current session."
+              " Please save the current value to silence this message."
+              '(erc-nick-default-face erc-default-face)
+              '(erc-button-nick-default-face erc-default-face))))
+        (when (or (null existing) localp)
+          (setq table (map-into (mapcar (lambda (f) (cons f f))
+                                        erc-track-faces-normal-list)
+                                '(hash-table :test equal :weakness value))))
+        (setq erc-track--normal-faces (or table existing))
+        (unless (or localp existing)
+          (erc-with-server-buffer (setq erc-track--normal-faces table))))
+    (kill-local-variable 'erc-track--normal-faces)))
+
 ;;; Visibility
 
 (defvar erc-buffer-activity nil
@@ -767,7 +858,12 @@ erc-track-select-mode-line-face
 face, if a member of `erc-track-faces-normal-list', to be
 replaced with another with lower priority face from NEW-FACES, if
 that face with highest priority in NEW-FACES is also a member of
-`erc-track-faces-normal-list'."
+`erc-track-faces-normal-list'.
+
+To put it another way, when CUR-FACE outranks all NEW-FACES and
+doesn't appear among them, it's eligible to be replaced with a
+fellow \"normal\" from NEW-FACES.  But if it does appear among
+them, it can't be replaced."
   (let ((choice (catch 'face
                   (dolist (candidate erc-track-faces-priority-list)
                     (when (or (equal candidate cur-face)
@@ -786,6 +882,53 @@ erc-track-select-mode-line-face
               choice))
         choice))))
 
+(defvar erc-track--alt-normals-function nil
+  "A function to possibly elect a \"normal\" face.
+Called with the current incumbent and the worthiest new contender
+followed by all new contending faces and so-called \"normal\"
+faces.  See `erc-track--select-mode-line-face' for their meanings
+and expected types.  This function should return a face or nil.")
+
+(defun erc-track--select-mode-line-face (cur-face new-faces ranks normals)
+  "Return CUR-FACE or a replacement for displaying in the mode-line, or nil.
+Expect RANKS to be a list of faces and both NORMALS and the car
+of NEW-FACES to be hash tables mapping faces to non-nil values.
+Assume the latter's makeup and that of RANKS to resemble
+`erc-track-face-normal-list' and `erc-track-faces-priority-list'.
+If NEW-FACES has a cdr, expect it to be its car's contents
+ordered from most recently seen (later in the buffer) to
+earliest.  In general, act like `erc-track-select-mode-line-face'
+except appeal to `erc-track--alt-normals-function' if it's
+non-nil, falling back on reconsidering NEW-FACES when CUR-FACE
+outranks all its members.  That is, choose the first among RANKS
+in NEW-FACES not equal to CUR-FACE.  Failing that, choose the
+first face in NEW-FACES that's also in NORMALS, assuming
+NEW-FACES has a cdr."
+  (cl-check-type erc-track-ignore-normal-contenders-p null)
+  (cl-check-type new-faces cons)
+  (when-let ((choice (catch 'face
+                       (dolist (candidate ranks)
+                         (when (or (equal candidate cur-face)
+                                   (gethash candidate (car new-faces)))
+                           (throw 'face candidate))))))
+    (or (and erc-track--alt-normals-function
+             (funcall erc-track--alt-normals-function
+                      cur-face choice new-faces normals))
+        (and (equal choice cur-face)
+             (gethash choice normals)
+             (catch 'face
+               (progn
+                 (dolist (candidate ranks)
+                   (when (and (not (equal candidate choice))
+                              (gethash candidate (car new-faces))
+                              (gethash choice normals))
+                     (throw 'face candidate)))
+                 (dolist (candidate (cdr new-faces))
+                   (when (and (not (equal candidate choice))
+                              (gethash candidate normals))
+                     (throw 'face candidate))))))
+        choice)))
+
 (defvar erc-track--skipped-msgs '(datestamp)
   "Values of `erc-msg' text prop to ignore.")
 
@@ -820,31 +963,43 @@ erc-track-modified-channels
 	;; (in the car), change its face attribute (in the cddr) if
 	;; necessary.  See `erc-modified-channels-alist' for the
 	;; exact data structure used.
-        (let ((faces (erc-faces-in (buffer-string)))
-              (erc-track-faces-priority-list
-               `(,@erc-track--attn-faces ,@erc-track-faces-priority-list)))
-	  (unless (and
-		   (or (eq erc-track-priority-faces-only 'all)
-		       (member this-channel erc-track-priority-faces-only))
-		   (not (catch 'found
-			  (dolist (f faces)
-			    (when (member f erc-track-faces-priority-list)
-			      (throw 'found t))))))
+        (when-let
+            ((faces (if erc-track-ignore-normal-contenders-p
+                        (erc-faces-in (buffer-string))
+                      (erc-track--get-faces-in-current-message)))
+             (normals erc-track--normal-faces)
+             (erc-track-faces-priority-list
+              `(,@erc-track--attn-faces ,@erc-track-faces-priority-list))
+             (ranks erc-track-faces-priority-list)
+             ((not (and
+                    (or (eq erc-track-priority-faces-only 'all)
+                        (member this-channel erc-track-priority-faces-only))
+                    (not (catch 'found
+                           (dolist (f ranks)
+                             (when (gethash f (or (car-safe faces) faces))
+                               (throw 'found t)))))))))
+          (progn ; FIXME remove `progn' on next major edit
 	    (if (not (assq (current-buffer) erc-modified-channels-alist))
 		;; Add buffer, faces and counts
 		(setq erc-modified-channels-alist
 		      (cons (cons (current-buffer)
 				  (cons
-                                   1 (erc-track-select-mode-line-face
-                                      nil faces)))
+                                   1 (if erc-track-ignore-normal-contenders-p
+                                         (erc-track-select-mode-line-face
+                                          nil faces)
+                                       (erc-track--select-mode-line-face
+                                        nil faces ranks normals))))
 			    erc-modified-channels-alist))
 	      ;; Else modify the face for the buffer, if necessary.
 	      (when faces
 		(let* ((cell (assq (current-buffer)
 				   erc-modified-channels-alist))
 		       (old-face (cddr cell))
-		       (new-face (erc-track-select-mode-line-face
-                                  old-face faces)))
+                       (new-face (if erc-track-ignore-normal-contenders-p
+                                     (erc-track-select-mode-line-face
+                                      old-face faces)
+                                   (erc-track--select-mode-line-face
+                                    old-face faces ranks normals))))
 		  (setcdr cell (cons (1+ (cadr cell)) new-face)))))
 	    ;; And display it
 	    (erc-modified-channels-display)))
@@ -873,6 +1028,30 @@ erc-faces-in
 	   (push cur faces)))
     faces))
 
+(defvar erc-track--face-reject-function nil
+  "Function called with face in current buffer to massage or reject.")
+
+(defun erc-track--get-faces-in-current-message ()
+  "Collect all faces in the narrowed buffer.
+Return a cons of a hash table and a list ordered from most
+recently seen to earliest seen."
+  (let ((i (text-property-not-all (point-min) (point-max) 'font-lock-face nil))
+        (seen (make-hash-table :test #'equal))
+        ;;
+        (rfaces ())
+        (faces (make-hash-table :test #'equal)))
+    (while-let ((i)
+                (cur (get-text-property i 'face)))
+      (unless (gethash cur seen)
+        (puthash cur t seen)
+        (when erc-track--face-reject-function
+          (setq cur (funcall erc-track--face-reject-function cur)))
+        (when cur
+          (push cur rfaces)
+          (puthash cur t faces)))
+      (setq i (next-single-property-change i 'font-lock-face)))
+    (cons faces rfaces)))
+
 ;;; Buffer switching
 
 (defvar erc-track-last-non-erc-buffer nil
diff --git a/test/lisp/erc/erc-track-tests.el b/test/lisp/erc/erc-track-tests.el
index ab8d708b721..4477727be8a 100644
--- a/test/lisp/erc/erc-track-tests.el
+++ b/test/lisp/erc/erc-track-tests.el
@@ -120,4 +120,134 @@ erc-track--erc-faces-in
     (should (erc-faces-in str0))
     (should (erc-faces-in str1)) ))
 
+;; This simulates an alternating bold/non-bold [#c] in the mode-line,
+;; i.e., an `erc-modified-channels-alist' that vacillates between
+;;
+;;   ((#<buffer #chan> 42 . erc-default-face))
+;;
+;; and
+;;
+;;   ((#<buffer #chan> 42 erc-nick-default-face erc-default-face))
+;;
+;; This is a fairly typical scenario where consecutive messages
+;; feature speaker and addressee button highlighting and otherwise
+;; plain message bodies.  This mapping of phony to real faces
+;; describes the picture in 5.6:
+;;
+;;   `1': (erc-button erc-default-face)                 ; URL
+;;   `2': (erc-nick-default-face erc-default-face)      ; mention
+;;   `3': erc-default-face                              ; body
+;;   `_': (erc-nick-default-face erc-nick-default-face) ; speaker
+;;
+;; The `_' represents a commonly occurring face (a <speaker>) that's
+;; not present in either option's default (standard) value.  It's a
+;; no-op from the POV of `erc-track-select-mode-line-face'.
+
+(ert-deftest erc-track-select-mode-line-face ()
+
+  ;; Observed (see key above).
+  (let ((erc-track-faces-priority-list '(1 2 3))
+        (erc-track-faces-normal-list   '(1 2 3)))
+
+    (should (equal 2 (erc-track-select-mode-line-face 3 '(2 _ 3))))
+    (should (equal 2 (erc-track-select-mode-line-face 2 '(2 _ 3))))
+    (should (equal 3 (erc-track-select-mode-line-face 2 '(_ 3))))
+    (should (equal 2 (erc-track-select-mode-line-face 3 '(2 3))))
+    (should (equal 3 (erc-track-select-mode-line-face 2 '(3))))
+
+    (should (equal 1 (erc-track-select-mode-line-face 1 '(2 1 3))))
+    (should (equal 1 (erc-track-select-mode-line-face 1 '(1 3))))
+    (should (equal 1 (erc-track-select-mode-line-face 1 '(1 3 2))))
+    (should (equal 1 (erc-track-select-mode-line-face 1 '(3 1)))))
+
+  ;; When the current face outranks all new faces and doesn't appear
+  ;; among them, it's eligible to be replaced with a fellow "normal"
+  ;; from those new faces.  But if it does appear among them, it's
+  ;; never replaced.
+  (let ((erc-track-faces-priority-list '(a b))
+        (erc-track-faces-normal-list   '(a b)))
+
+    (should (equal 'a (erc-track-select-mode-line-face 'a '(b a))))
+    (should (equal 'a (erc-track-select-mode-line-face 'a '(a b))))
+    (should (equal 'a (erc-track-select-mode-line-face 'b '(b a))))
+    (should (equal 'a (erc-track-select-mode-line-face 'b '(a b))))
+
+    (should (equal 'a (erc-track-select-mode-line-face 'b '(a))))
+    (should (equal 'b (erc-track-select-mode-line-face 'a '(b)))))
+
+  ;; The ordering of the "normal" list doesn't matter.
+  (let ((erc-track-faces-priority-list '(a b))
+        (erc-track-faces-normal-list   '(b a)))
+
+    (should (equal 'a (erc-track-select-mode-line-face 'a '(b a))))
+    (should (equal 'a (erc-track-select-mode-line-face 'a '(a b))))
+    (should (equal 'a (erc-track-select-mode-line-face 'b '(b a))))
+    (should (equal 'a (erc-track-select-mode-line-face 'b '(a b))))))
+
+(defun erc-track-tests--select-mode-line-face (ranked normals cases)
+  (setq normals (map-into (mapcar (lambda (f) (cons f t)) normals)
+                          '(hash-table :test equal)))
+  (pcase-dolist (`(,want ,cur-face ,new-faces) cases)
+
+    (ert-info ((format "Observed: {cur: %S, new: %S, want: %S}"
+                       cur-face new-faces want))
+      (setq new-faces (cons (map-into
+                             (mapcar (lambda (f) (cons f t)) new-faces)
+                             '(hash-table :test equal))
+                            (reverse new-faces)))
+      (should (equal want (funcall #'erc-track--select-mode-line-face
+                                   cur-face new-faces ranked normals))))))
+
+;; The main difference between these variants is that with the above,
+;; when given alternating lines like
+;;
+;;  CUR      NEW                          CHOICE
+;;   text     (mention $speaker text)  =>   mention
+;;   mention  ($speaker text)          =>   text
+;;
+;; we see the effect of alternating faces in the indicator.  But when
+;; given consecutive lines with a similar composition, like
+;;
+;;   text     (mention $speaker text)  =>   mention
+;;   text     (mention $speaker text)  =>   mention
+;;
+;; we lose the effect.  With the variant below, we get
+;;
+;;   text     (mention $speaker text)  =>   mention
+;;   text     (mention $speaker text)  =>   text
+;;
+
+(ert-deftest erc-track--select-mode-line-face ()
+  (should-not erc-track-ignore-normal-contenders-p)
+
+  ;; These are the same test cases from the previous test.  The syntax
+  ;; is (expected cur-face new-faces).
+  (erc-track-tests--select-mode-line-face
+   '(1 2 3) '(1 2 3)
+   '((2 3 (2 _ 3))
+     (3 2 (2 _ 3))
+     (3 2 (_ 3))
+     (2 3 (2 3))
+     (3 2 (3))
+     (2 1 (2 1 3))
+     (3 1 (1 3))
+     (2 1 (1 3 2))
+     (3 1 (3 1))))
+
+  (erc-track-tests--select-mode-line-face
+   '(a b) '(a b)
+   '((b a (b a))
+     (b a (a b))
+     (a b (b a))
+     (a b (a b))
+     (a b (a))
+     (b a (b))))
+
+  (erc-track-tests--select-mode-line-face
+   '(a b) '(b a)
+   '((b a (b a))
+     (b a (a b))
+     (a b (b a))
+     (a b (a b)))))
+
 ;;; erc-track-tests.el ends here
-- 
2.42.0


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From 105d66146f71f7d1060d845255d81c4fb9b9919d Mon Sep 17 00:00:00 2001
From: "F. Jason Park" <jp@neverwas.me>
Date: Mon, 13 Jun 2022 00:26:22 -0700
Subject: [PATCH 4/5] [5.7] Cache shortened channel names in erc-track

* lisp/erc/erc-track.el (erc-track--shortened-names): New variable to
stash both the latest inputs and most recent result of
`erc-track-shorten-function'.
(erc-track--shortened-names-current-hash,
erc-track--shortened-names-set, erc-track--shortened-names-get): New
pair of generalized-variable functions and helper variable for
accessing and mutating `erc-track--shorten-prefixes'.
(erc-modified-channels-display): Avoid redundant calls to
`erc-track-shorten-function'.  Mainly for use during batch processing.
* test/lisp/erc/erc-track-tests.el
(erc-track--shortened-names): New test.  (Bug#67767)
---
 lisp/erc/erc-track.el            | 42 +++++++++++++++++++++++++++++---
 test/lisp/erc/erc-track-tests.el | 36 +++++++++++++++++++++++++++
 2 files changed, 74 insertions(+), 4 deletions(-)

diff --git a/lisp/erc/erc-track.el b/lisp/erc/erc-track.el
index 490fc52d42c..a6a1539b044 100644
--- a/lisp/erc/erc-track.el
+++ b/lisp/erc/erc-track.el
@@ -382,6 +382,37 @@ erc-track-add-to-mode-line
 
 ;;; Shortening of names
 
+(defvar erc-track--shortened-names nil
+  "A cons of the last novel name-shortening params and the result.
+The CAR is a hash of environmental inputs such as options and
+parameters passed to `erc-track-shorten-function'.  Its effect is
+only really noticeable during batch processing.")
+
+(defvar erc-track--shortened-names-current-hash nil)
+
+(defun erc-track--shortened-names-set (_ shortened)
+  "Remember SHORTENED names with hash of contextual params."
+  (cl-assert erc-track--shortened-names-current-hash)
+  (setq erc-track--shortened-names
+        (cons erc-track--shortened-names-current-hash shortened)))
+
+(defun erc-track--shortened-names-get (channel-names)
+  "Cache CHANNEL-NAMES with various contextual parameters.
+For now, omit relevant options like `erc-track-shorten-start' and
+friends, even though they do affect the outcome, because they
+likely change too infrequently to matter over sub-second
+intervals and are unlikely to be let-bound or set locally."
+  (when-let ((hash (setq erc-track--shortened-names-current-hash
+                         (sxhash-equal (list channel-names
+                                             (buffer-list)
+                                             erc-track-shorten-function))))
+             (erc-track--shortened-names)
+             ((= hash (car erc-track--shortened-names))))
+    (cdr erc-track--shortened-names)))
+
+(gv-define-simple-setter erc-track--shortened-names-get
+                         erc-track--shortened-names-set)
+
 (defun erc-track-shorten-names (channel-names)
   "Call `erc-unique-channel-names' with the correct parameters.
 This function is a good value for `erc-track-shorten-function'.
@@ -797,10 +828,13 @@ erc-modified-channels-display
                                            (or (buffer-name buf)
                                                ""))
 					 buffers))
-		     (short-names (if (functionp erc-track-shorten-function)
-				      (funcall erc-track-shorten-function
-					       long-names)
-				    long-names))
+                     (erc-track--shortened-names-current-hash nil)
+                     (short-names
+                      (if (functionp erc-track-shorten-function)
+                          (with-memoization
+                              (erc-track--shortened-names-get long-names)
+                            (funcall erc-track-shorten-function long-names))
+                        long-names))
 		     strings)
 		(while buffers
 		  (when (car short-names)
diff --git a/test/lisp/erc/erc-track-tests.el b/test/lisp/erc/erc-track-tests.el
index 4477727be8a..ed3d190928f 100644
--- a/test/lisp/erc/erc-track-tests.el
+++ b/test/lisp/erc/erc-track-tests.el
@@ -104,6 +104,42 @@ erc-track--shorten-aggressive-max
                                       '("#emacs" "#vi"))
             '("#e" "#v"))) ))
 
+(ert-deftest erc-track--shortened-names ()
+  (let (erc-track--shortened-names
+        erc-track--shortened-names-current-hash
+        results)
+
+    (with-memoization (erc-track--shortened-names-get
+                       '("apple" "banana" "cherries"))
+      '("a" "b" "c"))
+    (should (integerp (car erc-track--shortened-names)))
+    (should (equal (cdr erc-track--shortened-names) '("a" "b" "c")))
+    (push erc-track--shortened-names results)
+
+    ;; Redundant call doesn't run.
+    (with-memoization (erc-track--shortened-names-get
+                       '("apple" "banana" "cherries"))
+      (should-not 'run)
+      '("a" "b" "c"))
+    (should (equal erc-track--shortened-names (car results)))
+
+    ;; Change in environment or context forces run.
+    (with-temp-buffer
+      (with-memoization (erc-track--shortened-names-get
+                         '("apple" "banana" "cherries"))
+        '("x" "y" "z")))
+    (should (and (integerp (car erc-track--shortened-names))
+                 (/= (car erc-track--shortened-names) (caar results))))
+    (should (equal (cdr erc-track--shortened-names) '("x" "y" "z")))
+    (push erc-track--shortened-names results)
+
+    (with-memoization (erc-track--shortened-names-get
+                       '("apple" "banana" "cherries"))
+      '("1" "2" "3"))
+    (should (and (integerp (car erc-track--shortened-names))
+                 (/= (car erc-track--shortened-names) (caar results))))
+    (should (equal (cdr erc-track--shortened-names) '("1" "2" "3")))))
+
 (ert-deftest erc-track--erc-faces-in ()
   "`erc-faces-in' should pick up both 'face and 'font-lock-face properties."
   (let ((str0 (copy-sequence "is bold"))
-- 
2.42.0


[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #7: 0005-5.7-Add-erc-track-integration-to-erc-nicks.patch --]
[-- Type: text/x-patch, Size: 13091 bytes --]

From e14973511bf0c845ceaac2121c95cc47c6b17ae5 Mon Sep 17 00:00:00 2001
From: "F. Jason Park" <jp@neverwas.me>
Date: Mon, 11 Dec 2023 01:30:48 -0800
Subject: [PATCH 5/5] [5.7] Add erc-track integration to erc-nicks

* lisp/erc/erc-button.el (erc-button--nick): Add `face-cache' slot.
(erc-button-add-nickname-buttons): Pass `erc-button--nick' object, if
created' as the boolean NICK-P parameter when calling
`erc-button-add-button'.  Keeping the latter ignorant
`erc-button--nick' is of course preferable, but some coordination is
now required to convey and use the face cache.  We could introduce an
abstraction, like a local variable, if this becomes an issue.
(erc-button-add-button): Use `erc--merge-prop' instead of
`erc-button-add-face' to apply button faces.  Hold off on deprecating
the latter because it provides unique functionality for nesting faces.
Also, consult NICK-P if it's an `erc-button--nick' object for the
various overriding faces it knows about.
* lisp/erc/erc-nicks.el (erc-nicks-track-faces): New option.
(erc-nicks--highlight-button): Set the `face-cache' slot of the
`erc-button--nick' object when `track' is loaded and initialized.
(erc-nicks-mode, erc-nicks-enable, erc-nicks-disable): Add and remove
`track' integration.
(erc-nicks--reject-uninterned-faces): New function to remove faces
created by `nicks' from buttonized speakers and mentions.  Conform
to `erc-track--face-reject-function' interface.
(erc-nicks--ourps, erc-nicks--check-normals): New function and helper
for `erc-track--alt-normals-function' interface.
(erc-nicks--setup-track-integration): New function.
(erc-nicks--remember-face-for-track): New function to cache
nick faces owned by this module.  (Bug#67767)
---
 lisp/erc/erc-button.el | 41 +++++++++++----------
 lisp/erc/erc-nicks.el  | 83 +++++++++++++++++++++++++++++++++++++++++-
 lisp/erc/erc.el        |  8 +++-
 3 files changed, 110 insertions(+), 22 deletions(-)

diff --git a/lisp/erc/erc-button.el b/lisp/erc/erc-button.el
index f10d7a2fce7..fc2511bad42 100644
--- a/lisp/erc/erc-button.el
+++ b/lisp/erc/erc-button.el
@@ -369,7 +369,8 @@ erc-button--nick
   ( nickname-face erc-button-nickname-face :type symbol
     :documentation "Temp `erc-button-nickname-face' while buttonizing.")
   ( mouse-face erc-button-mouse-face :type symbol
-    :documentation "Temp `erc-button-mouse-face' while buttonizing."))
+    :documentation "Function to return possibly cached face.")
+  ( face-cache nil :type (or null function)))
 
 ;; This variable is intended to serve as a "core" to be wrapped by
 ;; (built-in) modules during setup.  It's unclear whether
@@ -460,8 +461,7 @@ erc-button-add-nickname-buttons
                      (erc-bounds-of-word-at-point)))
          (word (buffer-substring-no-properties (car bounds) (cdr bounds)))
          (down (erc-downcase word)))
-      (let* ((erc-button-mouse-face erc-button-mouse-face)
-             (erc-button-nickname-face erc-button-nickname-face)
+      (let* ((nick-obj t)
              (cuser (and erc-channel-users
                          (or (gethash down erc-channel-users)
                              (funcall erc-button--fallback-cmem-function
@@ -470,19 +470,15 @@ erc-button-add-nickname-buttons
                        (and erc-server-users (gethash down erc-server-users))))
              (data (list word)))
         (when (or (not (functionp form))
-                  (and-let* ((user)
-                             (obj (funcall form (make-erc-button--nick
-                                                 :bounds bounds :data data
-                                                 :downcased down :user user
-                                                 :cuser (cdr cuser)))))
-                    (setq erc-button-mouse-face ; might be null
-                          (erc-button--nick-mouse-face obj)
-                          erc-button-nickname-face ; might be null
-                          (erc-button--nick-nickname-face obj)
-                          data (erc-button--nick-data obj)
-                          bounds (erc-button--nick-bounds obj))))
+                  (and user
+                       (setq nick-obj (funcall form (make-erc-button--nick
+                                                     :bounds bounds :data data
+                                                     :downcased down :user user
+                                                     :cuser (cdr cuser)))
+                             data (erc-button--nick-data nick-obj)
+                             bounds (erc-button--nick-bounds nick-obj))))
           (erc-button-add-button (car bounds) (cdr bounds) (nth 3 entry)
-                                 'nickp data))))))
+                                 nick-obj data))))))
 
 (defun erc-button-add-buttons-1 (regexp entry)
   "Search through the buffer for matches to ENTRY and add buttons."
@@ -541,13 +537,20 @@ erc-button-add-button
           (move-marker pos (point))))))
   (if nick-p
       (when erc-button-nickname-face
-        (erc-button-add-face from to erc-button-nickname-face))
+        (erc--merge-prop from to 'font-lock-face
+                         (or (and (erc-button--nick-p nick-p)
+                                  (erc-button--nick-nickname-face nick-p))
+                             erc-button-nickname-face)
+                         nil (and (erc-button--nick-p nick-p)
+                                  (erc-button--nick-face-cache nick-p))))
     (when erc-button-face
-      (erc-button-add-face from to erc-button-face)))
+      (erc--merge-prop from to 'font-lock-face erc-button-face)))
   (add-text-properties
    from to
-   (nconc (and erc-button-mouse-face
-               (list 'mouse-face erc-button-mouse-face))
+   (nconc (and-let* ((face (or (and (erc-button--nick-p nick-p)
+                                    (erc-button--nick-mouse-face nick-p))
+                               erc-button-mouse-face)))
+            (list 'mouse-face face))
           (list 'erc-callback fun)
           (list 'keymap erc-button-keymap)
           (list 'rear-nonsticky t)
diff --git a/lisp/erc/erc-nicks.el b/lisp/erc/erc-nicks.el
index 2f0c3261266..0b1e5e0c050 100644
--- a/lisp/erc/erc-nicks.el
+++ b/lisp/erc/erc-nicks.el
@@ -173,6 +173,20 @@ erc-nicks-key-suffix-format
 like \"@%-012n\"."
   :type 'string)
 
+(defcustom erc-nicks-track-faces 'prioritize
+  "Show nick faces in the `track' module's portion of the mode line.
+A value of nil means don't show nick faces at all.  A value of
+`defer' means have `track' consider nick faces only after those
+ranked faces in `erc-track-faces-normal-list'.  This has the
+effect of \"alternating\" between a ranked \"normal\" and a nick.
+The value `prioritize' means have `track' consider nick faces to
+be \"normal\" unless the current speaker is the same as the
+previous one, in which case pretend the value is `defer'.  Like
+most options in this module, updating the value mid-session is
+not officially supported, although cycling \\[erc-nicks-mode] may
+be worth a shot."
+  :type '(choice (const nil) (const defer) (const prioritize)))
+
 (defvar erc-nicks--max-skip-search 3 ; make this an option?
   "Max number of faces to visit when testing `erc-nicks-skip-faces'.")
 
@@ -516,7 +530,12 @@ erc-nicks--highlight-button
                                 'font-lock-face))
        (nick (erc-server-user-nickname (erc-button--nick-user nick-object)))
        (out (erc-nicks--highlight nick face)))
-    (setf (erc-button--nick-nickname-face nick-object) out))
+    (setf (erc-button--nick-nickname-face nick-object) out
+          ;;
+          (erc-button--nick-face-cache nick-object)
+          (and erc-nicks-track-faces
+               (bound-and-true-p erc-track--normal-faces)
+               #'erc-nicks--remember-face-for-track)))
   nick-object)
 
 (define-erc-module nicks nil
@@ -559,6 +578,8 @@ nicks
        erc-nicks--face-table (make-hash-table :test #'equal)))
    (setf (alist-get "Edit face" erc-button--nick-popup-alist nil nil #'equal)
          #'erc-nicks-customize-face)
+   (erc-nicks--setup-track-integration)
+   (add-hook 'erc-track-mode #'erc-nicks--setup-track-integration 50 t)
    (advice-add 'widget-create-child-and-convert :filter-args
                #'erc-nicks--redirect-face-widget-link))
   ((kill-local-variable 'erc-nicks--face-table)
@@ -570,8 +591,12 @@ nicks
    (kill-local-variable 'erc-nicks--downcased-skip-nicks)
    (when (fboundp 'erc-button--phantom-users-mode)
      (erc-button--phantom-users-mode -1))
+   (remove-function (local 'erc-track--face-reject-function)
+                    #'erc-nicks--reject-uninterned-faces)
    (remove-function (local 'erc-button--modify-nick-function)
                     #'erc-nicks--highlight-button)
+   (remove-function (local 'erc-track--alt-normals-function)
+                    #'erc-nicks--check-normals)
    (setf (alist-get "Edit face"
                     erc-button--nick-popup-alist nil 'remove #'equal)
          nil)
@@ -691,6 +716,62 @@ erc-nicks--colors-from-faces
                  (color (face-foreground face)))
         (push color out)))))
 
+(defun erc-nicks--reject-uninterned-faces (candidate)
+  "Remove own faces from CANDIDATE if it's a combination of faces."
+  (while-let ((next (car-safe candidate))
+              ((facep next))
+              ((not (intern-soft next))))
+    (setq candidate (cdr candidate)))
+  (if (and (consp candidate) (not (cdr candidate))) (car candidate) candidate))
+
+(define-inline erc-nicks--oursp (face)
+  (inline-quote
+   (and-let* ((sym (car-safe ,face))
+              ((symbolp sym))
+              ((get sym 'erc-nicks--key)))
+     sym)))
+
+(defun erc-nicks--check-normals (current contender contenders normals)
+  "Return a viable `nicks'-owned face from NORMALS in CONTENDERS.
+But only do so if the CURRENT face is also one of ours and in
+NORMALS and if the highest ranked CONTENDER among new faces is
+`erc-default-face', the lowest ranking default priority face."
+  (defvar erc-track--normal-faces)
+  (cl-assert erc-track--normal-faces)
+  (and-let* (((eq contender 'erc-default-face))
+             ((gethash current normals))
+             (spkr (erc-nicks--oursp current)))
+    (catch 'contender
+      (dolist (candidate (cdr contenders) contender)
+        (when-let (((not (equal candidate current)))
+                   ((gethash candidate normals))
+                   (s (erc-nicks--oursp candidate))
+                   ((not (eq s spkr))))
+          (throw 'contender candidate))))))
+
+(defun erc-nicks--setup-track-integration ()
+  "Restore traditional \"alternating normal\" face functionality to mode-line."
+  (when (bound-and-true-p erc-track-mode)
+    (pcase erc-nicks-track-faces
+      ;; Variant `defer' is handled elsewhere.
+      ('prioritize
+       (add-function :override (local 'erc-track--alt-normals-function)
+                     #'erc-nicks--check-normals))
+      ('nil
+       (add-function :override (local 'erc-track--face-reject-function)
+                     #'erc-nicks--reject-uninterned-faces)))))
+
+(defun erc-nicks--remember-face-for-track (face)
+  "Add FACE to local hash table maintained by `track' module."
+  (defvar erc-track--normal-faces)
+  (cl-assert erc-track--normal-faces)
+  (or (gethash face erc-track--normal-faces)
+      (if-let ((sym (or (car-safe face) face))
+               ((symbolp sym))
+               ((get sym 'erc-nicks--key)))
+          (puthash face face erc-track--normal-faces)
+        face)))
+
 (provide 'erc-nicks)
 
 ;;; erc-nicks.el ends here
diff --git a/lisp/erc/erc.el b/lisp/erc/erc.el
index 62fdc0ad6e8..2734c602fa2 100644
--- a/lisp/erc/erc.el
+++ b/lisp/erc/erc.el
@@ -3351,12 +3351,14 @@ erc--merge-text-properties-p
 ;; values and optionally dispense archetypal constants in their place
 ;; in order to ensure all occurrences of some list (a b) across all
 ;; text-properties in all ERC buffers are actually the same object.
-(defun erc--merge-prop (from to prop val &optional object)
+(defun erc--merge-prop (from to prop val &optional object cache-fn)
   "Combine existing PROP values with VAL between FROM and TO in OBJECT.
 For spans where PROP is non-nil, cons VAL onto the existing
 value, ensuring a proper list.  Otherwise, just set PROP to VAL.
 When VAL is itself a list, prepend its members onto an existing
-value.  See also `erc-button-add-face'."
+value.  Call CACHE-FN, when given, with the new value for prop.
+It must return a suitable replacement or the same value.  See
+also `erc-button-add-face'."
   (let ((old (get-text-property from prop object))
         (pos from)
         (end (next-single-property-change from prop object to))
@@ -3370,6 +3372,8 @@ erc--merge-prop
                           (append val (ensure-list old))
                         (cons val (ensure-list old))))
                   val))
+      (when cache-fn
+        (setq new (funcall cache-fn new)))
       (put-text-property pos end prop new object)
       (setq pos end
             old (get-text-property pos prop object)
-- 
2.42.0


^ permalink raw reply related	[flat|nested] 9+ messages in thread

* bug#67767: 30.0.50; ERC 5.6: Add track integration to the nicks module
       [not found] ` <8734w6yz76.fsf@neverwas.me>
@ 2023-12-18 14:51   ` J.P.
  0 siblings, 0 replies; 9+ messages in thread
From: J.P. @ 2023-12-18 14:51 UTC (permalink / raw)
  To: 67767-done; +Cc: emacs-erc

A version of this has been installed (perhaps prematurely) as

  8e06f224a9e * Add erc-track integration to erc-nicks

Also included are some superficial changes to a few essential variables
and data structures, such as `erc-channel-users'. See etc/ERC-NEWS for
details.

Closing for now.





^ permalink raw reply	[flat|nested] 9+ messages in thread

* bug#67767: 30.0.50; ERC 5.6: Add track integration to the nicks module
  2023-12-11 15:28 bug#67767: 30.0.50; ERC 5.6: Add track integration to the nicks module J.P.
                   ` (3 preceding siblings ...)
       [not found] ` <8734w6yz76.fsf@neverwas.me>
@ 2024-09-30  0:34 ` J.P.
       [not found] ` <87ed52q8rd.fsf@neverwas.me>
  5 siblings, 0 replies; 9+ messages in thread
From: J.P. @ 2024-09-30  0:34 UTC (permalink / raw)
  To: 67767; +Cc: emacs-erc

[-- Attachment #1: Type: text/plain, Size: 1798 bytes --]

"J.P." <jp@neverwas.me> writes:

> ERC's `nicks' module doesn't currently play nice with `track'. Enabling
> it breaks the cycling effect normally occurring among faces in
> `erc-track-faces-normal-list' [1].
>
[...]
>
> [1] Although, what we typically perceive as this effect is somewhat
>     illusory, if not underrealized. See comments preceding the new tests
>     in the first patch.

It's been pointed out that the most recent attempt at improving the
situation, especially with regard to the option `erc-nicks-track-faces',
ended up perpetuating rather unintuitive aspects of the original
behavior in certain common situations. While the particulars are tedious
to lay out, a somewhat relatable example is a speaker with a
`nicks'-owned face speaking immediately after an inserted JOIN message
(displayed in `erc-notice-face'). Based on the doc string of
`erc-nicks-track-faces', you'd think the `track' segment would favor the
`nicks'-owned face, but that's not currently so. The attached patch aims
to rectify this as well as address other, similar surprises.

Another problem with the current "normals" behavior is that it fails to
adequately exhibit the "flickering" effect when `nicks' _isn't_ enabled.
You can see this by connecting using the default configuration. Notice
that the mode-line segment stays on `erc-default-face while users are
conversing so long as they don't mention one another. However, the
"normals" feature was always meant to provide more responsive feedback
to clearly indicate active conversations (including monologuing). The
patch tries to address this by adding the default buttonized speaker
face to the related options `erc-track-faces-priority-list' and
`erc-track-faces-normal-list'. If there's a smarter way, hopefully
someone will speak up.

Thanks.


[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #2: 0001-5.6.1-Fix-prioritize-variant-of-erc-nicks-track-face.patch --]
[-- Type: text/x-patch, Size: 50950 bytes --]

From 75f12151384db0e257b6367ce357ef5d8bcfae6b Mon Sep 17 00:00:00 2001
From: "F. Jason Park" <jp@neverwas.me>
Date: Thu, 26 Sep 2024 21:34:25 -0700
Subject: [PATCH] [5.6.1] Fix prioritize variant of erc-nicks-track-faces

* etc/ERC-NEWS: Mention changes to `erc-track-faces-normal-list'
and `erc-track-faces-priority-list'.
* lisp/erc/erc-nicks.el (erc-nicks-track-faces): Update doc.
(erc-nicks--reject-uninterned-faces): Use helper.
(erc-nicks-track-normal-max-rank): New variable.
(erc-nicks--check-normals): Change behavior to also consider replacing
the current mode-line face when it's not `nicks' owned if it's
explicitly ranked lower than `erc-default-face'.
* lisp/erc/erc-track.el (erc-track--massage-nick-button-faces): Change
type of symbol property `erc-track--obsolete-faces' for options
`erc-track-faces-priority-list' and friends from a boolean to an alist.
(erc-track-faces-priority-list): Add new face for buttonized speakers.
(erc-track-faces-normal-list): Add new face for buttonized speakers.
Also add `erc-notice-face'.
(erc-track--priority-faces): New local variable to cache ranked faces.
(erc-track--setup): Initialize new `erc-track--priority-faces' variable
and refactor.
(erc-track--alt-normals-function): Doc.
(erc-track--select-mode-line-face): Update expected type of `ranks'
parameter.
(erc-track-modified-channels): Fix wrong-type bug occurring when
`erc-track-ignore-normal-contenders-p' and
`erc-track-priority-faces-only' are both non-nil.  Also fix subtle
compatibility oversight regarding an empty face list returned by
`erc-track--collect-faces-in'.
* test/lisp/erc/erc-nicks-tests.el: Load helpers and fixtures library.
(erc-nicks-tests--track-faces): New function.
(erc-nicks-track-faces/prioritize, erc-nicks-track-faces/defer)
(erc-nicks-track-faces/nil): New tests.
* test/lisp/erc/erc-track-tests.el
(erc-track-tests--select-mode-line-face): Update expected type of mocked
parameter.
(erc-track-tests--modified-channels/baseline): New function.
(erc-track-modified-channels/baseline)
(erc-track-modified-channels/baseline/mention)
(erc-track-modified-channels/baseline/ignore)
(erc-track-modified-channels/baseline/mention/ignore)
(erc-track-modified-channels/priority-only-all/baseline)
(erc-track-modified-channels/priority-only-all/sans-notice): New tests.
* test/lisp/erc/resources/erc-tests-common.el
(erc-tests-common-track-modified-channels)
(erc-tests-common-track-modified-channels-sans-setup): New functions.
(Bug67767)
---
 etc/ERC-NEWS                                |   7 +
 lisp/erc/erc-nicks.el                       |  44 ++--
 lisp/erc/erc-track.el                       | 219 ++++++++++------
 test/lisp/erc/erc-nicks-tests.el            | 222 ++++++++++++++++-
 test/lisp/erc/erc-track-tests.el            | 262 +++++++++++++++++++-
 test/lisp/erc/resources/erc-tests-common.el |  43 ++++
 6 files changed, 700 insertions(+), 97 deletions(-)

diff --git a/etc/ERC-NEWS b/etc/ERC-NEWS
index b267db5502e..d5df54256af 100644
--- a/etc/ERC-NEWS
+++ b/etc/ERC-NEWS
@@ -35,6 +35,13 @@ has been removed.
 Option 'erc-keep-place-indicator-truncation' manages the tension between
 truncation and place keeping, prioritizing one or the other.
 
+** Updated defaults for the 'track' module's face-list options.
+The default values of options 'erc-track-faces-priority-list' and
+'erc-track-faces-normal-list' have both gained a face for buttonized
+speaker names, with the latter option also gaining 'erc-notice-face'.
+This was done to provide a more frequent and practical indication of
+channel activity in keeping with the module's original design.
+
 \f
 * Changes in ERC 5.6
 
diff --git a/lisp/erc/erc-nicks.el b/lisp/erc/erc-nicks.el
index a0d6d17d732..a17900d9330 100644
--- a/lisp/erc/erc-nicks.el
+++ b/lisp/erc/erc-nicks.el
@@ -179,12 +179,12 @@ erc-nicks-track-faces
 `defer' means have `track' consider nick faces only after those
 ranked faces in `erc-track-faces-normal-list'.  This has the
 effect of \"alternating\" between a ranked \"normal\" and a nick.
-The value `prioritize' means have `track' consider nick faces to
-be \"normal\" unless the current speaker is the same as the
-previous one, in which case pretend the value is `defer'.  Like
-most options in this module, updating the value mid-session is
-not officially supported, although cycling \\[erc-nicks-mode] may
-be worth a shot."
+A value of `prioritize' works like `defer' when speakers stay the
+same but allows a new speaker's face to impersonate a ranked
+normal so nick faces can alternate back-to-back.  Like most
+options in this module, updating the value mid-session is not
+officially supported, although cycling \\[erc-nicks-mode] may be
+worth a shot."
   :type '(choice (const nil) (const defer) (const prioritize)))
 
 (defvar erc-nicks--max-skip-search 3 ; make this an option?
@@ -724,7 +724,7 @@ erc-nicks--reject-uninterned-faces
               ((facep next))
               ((not (intern-soft next))))
     (setq candidate (cdr candidate)))
-  (if (and (consp candidate) (not (cdr candidate))) (car candidate) candidate))
+  (erc--solo candidate))
 
 (define-inline erc-nicks--oursp (face)
   (inline-quote
@@ -733,16 +733,30 @@ erc-nicks--oursp
               ((get sym 'erc-nicks--key)))
      sym)))
 
-(defun erc-nicks--check-normals (current contender contenders normals)
-  "Return a viable `nicks'-owned face from NORMALS in CONTENDERS.
-But only do so if the CURRENT face is also one of ours and in
-NORMALS and if the highest ranked CONTENDER among new faces is
-`erc-default-face'."
-  (and-let* (((eq contender 'erc-default-face))
+(defvar erc-nicks-track-normal-max-rank 'erc-default-face
+  "Highest priority normal face still eligible to alternate with `nicks' faces.
+Must appear in both `erc-track-faces-priority-list' and
+`erc-track-faces-normal-list'.")
+
+(defun erc-nicks--check-normals (current contender contenders ranks normals)
+  "Return a viable non-CURRENT `nicks' face in CONTENDERS.
+But only do so if CURRENT and CONTENDER are \"normal\" faces either
+unranked or at or below `erc-nicks-track-normal-max-rank'.  See
+`erc-track--select-mode-line-face' for the expected types of CONTENDERS,
+RANKS, and NORMALS."
+  (and-let* (((or (null contender) (gethash contender normals)))
              ((or (null current) (gethash current normals)))
-             (spkr (or (null current) (erc-nicks--oursp current))))
+             (threshold (gethash erc-nicks-track-normal-max-rank (car ranks)))
+             ((<= threshold (or (gethash contender (car ranks))
+                                ;; Unranked `contender' always replaceable.
+                                most-positive-fixnum)))
+             (spkr (or (erc-nicks--oursp current)
+                       ;; Use t to mean `current' is not a nick face but
+                       ;; replaceable nonetheless.
+                       (null current)
+                       (<= threshold (or (gethash current (car ranks)) 0)))))
     (catch 'contender
-      (dolist (candidate (cdr contenders) contender)
+      (dolist (candidate (cdr contenders))
         (when-let (((not (equal candidate current)))
                    ((gethash candidate normals))
                    (s (erc-nicks--oursp candidate))
diff --git a/lisp/erc/erc-track.el b/lisp/erc/erc-track.el
index f40960e4a22..82e5f402910 100644
--- a/lisp/erc/erc-track.el
+++ b/lisp/erc/erc-track.el
@@ -161,25 +161,33 @@ erc-track-use-faces
 \(e.g. `erc-pal-face' is used if a pal sent a message to that channel.)"
   :type 'boolean)
 
+;; In an emergency, users can opt out of this migration with:
+;;
+;;   (put 'erc-track-faces-priority-list 'erc-track--obsolete-faces t)
+;;   (put 'erc-track-faces-normal-list 'erc-track--obsolete-faces t)
+;;
 (defun erc-track--massage-nick-button-faces (sym val &optional set-fn)
-  "Transform VAL of face-list option SYM to have new defaults.
-Use `set'-compatible SET-FN when given.  If an update was
-performed, set the symbol property `erc-track--obsolete-faces' of
-SYM to t."
-  (let* ((changedp nil)
-         (new (mapcar
-               (lambda (f)
-                 (if (and (eq (car-safe f) 'erc-nick-default-face)
-                          (equal f '(erc-nick-default-face erc-default-face)))
-                     (progn
-                       (setq changedp t)
-                       (put sym 'erc-track--obsolete-faces t)
-                       (cons 'erc-button-nick-default-face (cdr f)))
-                   f))
-               val)))
-    (if set-fn
-        (funcall set-fn sym (if changedp new val))
-      (set-default sym (if changedp new val)))))
+  "Transform VAL of face-list option SYM to remove/replace obsolete items.
+Use `set'-compatible SET-FN when given.  Record any migrations as cons
+cells of (OLD . NEW) in the symbol property `erc-track--obsolete-faces'
+of SYM."
+  (let* ((oldface '(erc-nick-default-face erc-default-face))
+         (newface '(erc-button-nick-default-face erc-default-face))
+         (migrations (get sym 'erc-track--obsolete-faces))
+         (new (if migrations
+                  val
+                (delq nil
+                      (mapcar
+                       (lambda (f)
+                         (if (equal f oldface)
+                             (setf (alist-get oldface migrations
+                                              nil nil #'equal)
+                                   (and (not (member newface val)) newface))
+                           f))
+                       val)))))
+    (when migrations
+      (put sym 'erc-track--obsolete-faces migrations))
+    (if set-fn (funcall set-fn sym new) (set-default sym new))))
 
 (defcustom erc-track-faces-priority-list
   '(erc-error-face
@@ -191,6 +199,7 @@ erc-track-faces-priority-list
     (erc-button erc-default-face)
     erc-dangerous-host-face
     erc-nick-default-face
+    (erc-button-nick-default-face erc-nick-default-face)
     (erc-button-nick-default-face erc-default-face)
     erc-default-face
     erc-action-face
@@ -204,7 +213,7 @@ erc-track-faces-priority-list
 
 Note that ERC prioritizes certain faces reserved for critical
 messages regardless of this option's value."
-  :package-version '(ERC . "5.6")
+  :package-version '(ERC . "5.6.1")
   :set #'erc-track--massage-nick-button-faces
   :type (erc--with-dependent-type-match
          (repeat (choice face (repeat :tag "Combination" face)))
@@ -229,8 +238,10 @@ erc-track-faces-normal-list
   '((erc-button erc-default-face)
     erc-dangerous-host-face
     erc-nick-default-face
+    (erc-button-nick-default-face erc-nick-default-face)
     (erc-button-nick-default-face erc-default-face)
     erc-default-face
+    erc-notice-face
     erc-action-face)
   "A list of faces considered to be part of normal conversations.
 This list is used to highlight active buffer names in the mode line.
@@ -246,7 +257,7 @@ erc-track-faces-normal-list
 \\[erc-track-mode].
 
 The effect may be disabled by setting this variable to nil."
-  :package-version '(ERC . "5.6")
+  :package-version '(ERC . "5.6.1")
   :set #'erc-track--massage-nick-button-faces
   :type (erc--with-dependent-type-match
          (repeat (choice face (repeat :tag "Combination" face)))
@@ -636,49 +647,79 @@ erc-track-when-inactive
 	       (erc-track-enable))
 	   (set sym val))))
 
+(defvar-local erc-track--priority-faces nil
+  "Local copy of `erc-track-faces-priority-list' as a hash table.
+Keys are faces and values are rank integers (smaller is more important).")
+
 (defvar-local erc-track--normal-faces nil
-  "Local copy of `erc-track-faces-normal-list' as a hash table.")
+  "Local copy of `erc-track-faces-normal-list' as a hash table.
+Keys and values are faces.  The table is weak valued so it can double as
+a buttonizing cache.  See `erc-button-add-button' and `erc--merge-prop'.")
 
 (defun erc-track--setup ()
   "Initialize a buffer for use with the `track' module.
-If this is a server buffer or `erc-track-faces-normal-list' is
-locally bound, create a new `erc-track--normal-faces' for the
-current buffer.  Otherwise, set the local value to the server
-buffer's."
+If this is a server buffer or either `erc-track-faces-normal-list' or
+`erc-track-faces-priority-list' is locally bound, create a new cache
+table with corresponding local variable `erc-track--normal-faces' or
+`erc-track--priority-faces'.  Otherwise, in target buffers with no local
+binding, set the cache variable's local value to that of server's."
   (if erc-track-mode
-      (let ((existing (erc-with-server-buffer erc-track--normal-faces))
-            (localp (and erc--target
-                         (local-variable-p 'erc-track-faces-normal-list)))
-            (opts '(erc-track-faces-normal-list erc-track-faces-priority-list))
-            warnp table)
+      (let (warnp)
         ;; Don't bother warning users who've disabled `button'.
-        (unless (or erc--target (not (or (bound-and-true-p erc-button-mode)
-                                         (memq 'button erc-modules))))
-          (when (or localp (local-variable-p 'erc-track-faces-priority-list))
-            (dolist (opt opts)
+        (unless (or erc--target
+                    (not (or (bound-and-true-p erc-button-mode)
+                             (memq 'button erc-modules))))
+          (dolist (opt '(erc-track-faces-normal-list
+                         erc-track-faces-priority-list))
+            (when (local-variable-p opt)
               (erc-track--massage-nick-button-faces opt (symbol-value opt)
-                                                    #'set)))
-          (dolist (opt opts)
-            (when (get opt 'erc-track--obsolete-faces)
-              (push opt warnp)
+                                                    #'set))
+            (when-let ((migrations (get opt 'erc-track--obsolete-faces))
+                       ((consp migrations)))
+              (push (cons opt
+                          (mapcar (pcase-lambda (`(,old . ,new))
+                                    (format (if new "changed %s to %s"
+                                              "removed %s")
+                                            old new))
+                                  migrations))
+                    warnp)
               (put opt 'erc-track--obsolete-faces nil)))
           (when warnp
-            (erc--warn-once-before-connect 'erc-track-mode
-              (if (cdr warnp) "Options " "Option ")
-              (mapconcat (lambda (o) (format "`%S'" o)) warnp " and ")
-              (if (cdr warnp) " contain" " contains")
-              " an obsolete item, %S, intended to match buttonized nicknames."
-              " ERC has changed it to %S for the current session."
-              " Please save the current value to silence this message."
-              '(erc-nick-default-face erc-default-face)
-              '(erc-button-nick-default-face erc-default-face))))
-        (when (or (null existing) localp)
-          (setq table (map-into (mapcar (lambda (f) (cons f f))
-                                        erc-track-faces-normal-list)
-                                '(hash-table :test equal :weakness value))))
-        (setq erc-track--normal-faces (or table existing))
-        (unless (or localp existing)
-          (erc-with-server-buffer (setq erc-track--normal-faces table))))
+            (pcase-dolist (`(,opt . ,migrations) warnp)
+              (erc--warn-once-before-connect 'erc-track-mode
+                "Option `%S' contains "
+                (if (cdr migrations) "obsolete items." "an obsolete item.")
+                " ERC has done the following for the current session: %s."
+                " Please review these changes and, if convinced,"
+                " silence this message by saving the current value."
+                opt (string-join migrations ", ")))))
+        ;; Set `erc-track--priority-faces' cache to new or shared value.
+        (let* ((localp (and erc--target
+                            (local-variable-p 'erc-track-faces-priority-list)))
+               (existing (erc-with-server-buffer erc-track--priority-faces))
+               (table (or (and (not localp) existing)
+                          (let ((p 0))
+                            (map-into
+                             (mapcar (lambda (f) (cons f (cl-incf p)))
+                                     (append erc-track--attn-faces
+                                             erc-track-faces-priority-list))
+                             `(hash-table :test equal))))))
+          (setq erc-track--priority-faces table)
+          (unless (or localp existing)
+            (erc-with-server-buffer (setq erc-track--priority-faces table))))
+        ;; Likewise for `erc-track--normal-faces' cache.
+        (let* ((localp (and erc--target
+                            (local-variable-p 'erc-track-faces-normal-list)))
+               (existing (erc-with-server-buffer erc-track--normal-faces))
+               (table (or (and (not localp) existing)
+                          (map-into (mapcar (lambda (f) (cons f f))
+                                            erc-track-faces-normal-list)
+                                    `(hash-table :test equal
+                                                 :weakness value)))))
+          (setq erc-track--normal-faces table)
+          (unless (or localp existing)
+            (erc-with-server-buffer (setq erc-track--normal-faces table)))))
+    (kill-local-variable 'erc-track--priority-faces)
     (kill-local-variable 'erc-track--normal-faces)))
 
 ;;; Visibility
@@ -915,44 +956,54 @@ erc-track-select-mode-line-face
 (defvar erc-track--alt-normals-function nil
   "A function to possibly elect a \"normal\" face.
 Called with the current incumbent and the worthiest new contender
-followed by all new contending faces and so-called \"normal\"
-faces.  See `erc-track--select-mode-line-face' for their meanings
-and expected types.  This function should return a face or nil.")
+followed by all new contending faces, ranked faces, and so-called
+\"normal\" faces.  See `erc-track--select-mode-line-face' for their
+meanings and expected types.  This function should return a face or nil.")
 
 (defun erc-track--select-mode-line-face (cur-face new-faces ranks normals)
   "Return CUR-FACE or a replacement for displaying in the mode-line, or nil.
-Expect RANKS to be a list of faces and both NORMALS and the car
-of NEW-FACES to be hash tables mapping faces to non-nil values.
-Assume the latter's makeup and that of RANKS to resemble
-`erc-track-faces-normal-list' and `erc-track-faces-priority-list'.
-If NEW-FACES has a cdr, expect it to be its car's contents
-ordered from most recently seen (later in the buffer) to
-earliest.  In general, act like `erc-track-select-mode-line-face'
-except appeal to `erc-track--alt-normals-function' if it's
-non-nil, falling back on reconsidering NEW-FACES when CUR-FACE
-outranks all its members.  That is, choose the first among RANKS
-in NEW-FACES not equal to CUR-FACE.  Failing that, choose the
-first face in NEW-FACES that's also in NORMALS, assuming
-NEW-FACES has a cdr."
+Expect NEW-FACES to be a cons cell whose car is a hash table mapping
+faces present in the applicable region to t and whose cdr is its car's
+contents ordered from most recently seen (later in the buffer) to
+earliest.  Expect RANKS to be a cons cell whose car is a hash table
+similar to `erc-track--priority-faces' and whose cdr is a list of
+prioritized faces resembling `erc-track-faces-priority-list'.  Expect
+NORMALS to be a hash table mapping faces to themselves.  In general, act
+identically to `erc-track-select-mode-line-face', except appeal to
+`erc-track--alt-normals-function' if it's non-nil, and fall back on
+reconsidering only NEW-FACES appearing in NORMALS when CUR-FACE is
+itself \"normal\" and outranks all NEW-FACES.  That is, choose the first
+among RANKS in both NEW-FACES and NORMALS not equal to CUR-FACE.
+Failing that, choose the first face in both NEW-FACES and NORMALS."
   (cl-check-type erc-track-ignore-normal-contenders-p null)
   (cl-check-type new-faces cons)
+  ;; Choose the highest ranked face in `erc-track-faces-priority-list'
+  ;; that's either `cur-face' itself or one appearing in the region
+  ;; being processed.
   (when-let ((choice (catch 'face
-                       (dolist (candidate ranks)
+                       (dolist (candidate (cdr ranks))
                          (when (or (equal candidate cur-face)
                                    (gethash candidate (car new-faces)))
                            (throw 'face candidate))))))
     (or (and erc-track--alt-normals-function
              (funcall erc-track--alt-normals-function
-                      cur-face choice new-faces normals))
+                      cur-face choice new-faces ranks normals))
+        ;; If `choice' is still `cur-face' and also a "normal", attempt
+        ;; to choose another normal in order to produce the flickering
+        ;; effect mentioned in the doc of `erc-track-faces-normal-list'.
         (and (equal choice cur-face)
              (gethash choice normals)
              (catch 'face
+               ;; If ranked "normal" faces other than `choice' appear in
+               ;; the region, return the most important one.
                (progn
-                 (dolist (candidate ranks)
+                 (dolist (candidate (cdr ranks))
                    (when (and (not (equal candidate choice))
                               (gethash candidate (car new-faces))
                               (gethash choice normals))
                      (throw 'face candidate)))
+                 ;; Otherwise, go with any "normal" face other than
+                 ;; `choice' in the region.
                  (dolist (candidate (cdr new-faces))
                    (when (and (not (equal candidate choice))
                               (gethash candidate normals))
@@ -996,14 +1047,24 @@ erc-track-modified-channels
              (normals erc-track--normal-faces)
              (erc-track-faces-priority-list
               `(,@erc-track--attn-faces ,@erc-track-faces-priority-list))
-             (ranks erc-track-faces-priority-list)
+             (ranks (cons erc-track--priority-faces
+                          erc-track-faces-priority-list))
              ((not (and
                     (or (eq erc-track-priority-faces-only 'all)
                         (member this-channel erc-track-priority-faces-only))
-                    (not (catch 'found
-                           (dolist (f ranks)
-                             (when (gethash f (or (car-safe faces) faces))
-                               (throw 'found t)))))))))
+                    ;; Iterate over the shorter of `ranks' and `faces'.
+                    (let* ((r>fp (or erc-track-ignore-normal-contenders-p
+                                     (> (hash-table-count (car ranks))
+                                        (hash-table-count (car faces)))))
+                           (elems (cond ((not r>fp) (cdr ranks)) ; f>=r
+                                        (erc-track-ignore-normal-contenders-p
+                                         faces)
+                                        ((cdr faces))))
+                           (table (if r>fp (car ranks) (car faces))))
+                      (not (catch 'found
+                             (dolist (f elems)
+                               (when (gethash f table)
+                                 (throw 'found t))))))))))
           (progn ; FIXME remove `progn' on next major edit
 	    (if (not (assq (current-buffer) erc-modified-channels-alist))
 		;; Add buffer, faces and counts
@@ -1017,7 +1078,7 @@ erc-track-modified-channels
                                         nil faces ranks normals))))
 			    erc-modified-channels-alist))
 	      ;; Else modify the face for the buffer, if necessary.
-	      (when faces
+              (when (or erc-track-ignore-normal-contenders-p (cdr faces))
 		(let* ((cell (assq (current-buffer)
 				   erc-modified-channels-alist))
 		       (old-face (cddr cell))
diff --git a/test/lisp/erc/erc-nicks-tests.el b/test/lisp/erc/erc-nicks-tests.el
index 08080d249d5..75cb98b8407 100644
--- a/test/lisp/erc/erc-nicks-tests.el
+++ b/test/lisp/erc/erc-nicks-tests.el
@@ -30,8 +30,11 @@
 
 ;;; Code:
 
-(require 'ert-x)
 (require 'erc-nicks)
+(require 'ert-x)
+(eval-and-compile
+  (let ((load-path (cons (ert-resource-directory) load-path)))
+    (require 'erc-tests-common)))
 
 ;; This function replicates the behavior of older "invert" strategy
 ;; implementations from EmacsWiki, etc.  The values for the lower and
@@ -568,4 +571,221 @@ erc-nicks--create-coerced-pool
 
     (should (equal erc-nicks--colors-rejects '(t)))))
 
+(declare-function erc-track-modified-channels "erc-track" ())
+
+(defun erc-nicks-tests--track-faces (test)
+  (require 'erc-track)
+  (defvar erc-modified-channels-alist)
+  (defvar erc-track--normal-faces)
+
+  (erc-tests-common-make-server-buf)
+  (erc-nicks-mode +1)
+
+  (let ((erc-modules (cons 'nicks erc-modules))
+        ;; Pretend these faces were added in response-handling during
+        ;; insertion modification by buttonizing hooks.  See
+        ;; `erc-nicks--highlight-button'.
+        (add-face (lambda (face)
+                    (erc-nicks--remember-face-for-track ; speaker
+                     (list face 'erc-nick-default-face))
+                    (erc-nicks--remember-face-for-track ; mention
+                     (list face 'erc-default-face))))
+        ;;
+        bob-face alice-face assert-result)
+
+    (with-current-buffer (erc--open-target "#chan")
+      (should erc-nicks-mode)
+      (should (setq bob-face (erc-nicks--get-face "bob" "bob@foonet")))
+      (should (setq alice-face (erc-nicks--get-face "alice" "alice@foonet")))
+
+      (erc-tests-common-track-modified-channels-sans-setup
+
+       (lambda (set-faces)
+
+         (setq assert-result ; fixture binds `erc-modified-channels-alist'
+               (lambda (result)
+                 (should (equal (alist-get (current-buffer)
+                                           erc-modified-channels-alist)
+                                result))))
+
+         (funcall test set-faces assert-result add-face
+                  bob-face alice-face)))))
+
+  (erc-tests-common-kill-buffers))
+
+(ert-deftest erc-nicks-track-faces/prioritize ()
+  (should (eq erc-nicks-track-faces 'prioritize))
+  (erc-nicks-tests--track-faces
+   (lambda (set-faces assert-result add-face bob-face alice-face)
+
+     (defvar erc-track--alt-normals-function)
+     (should erc-track--alt-normals-function)
+
+     (funcall add-face bob-face)
+     (funcall add-face alice-face)
+
+     ;; Simulate a JOIN.
+     (funcall set-faces '(erc-notice-face))
+     (erc-track-modified-channels)
+     (funcall assert-result '(1 . erc-notice-face))
+
+     ;; Someone speaks, and the mode-line changes to a `nicks' owned
+     ;; composite face for the speaker.
+     (funcall set-faces `(erc-timestamp-face
+                          (,bob-face erc-nick-default-face)
+                          erc-default-face))
+     (erc-track-modified-channels)
+     (funcall assert-result `(2 ,bob-face erc-nick-default-face))
+
+     ;; That same someone speaks, and the mode-line indicator changes to
+     ;; another "normal" face in the message body.
+     (funcall set-faces `(erc-timestamp-face
+                          (,bob-face erc-nick-default-face)
+                          erc-default-face))
+     (erc-track-modified-channels)
+     (funcall assert-result '(3 . erc-default-face))
+
+     ;; And yet again, which results in the indicator going back to one.
+     (funcall set-faces `(erc-timestamp-face
+                          (,bob-face erc-nick-default-face)
+                          erc-default-face))
+     (erc-track-modified-channels)
+     (funcall assert-result `(4 ,bob-face erc-nick-default-face))
+
+     ;; Now the same person mentions another server user, resulting in a
+     ;; change to *that* `nicks' owned face because it appears later in
+     ;; the message content (timestamp is last).
+     (funcall set-faces `(erc-timestamp-face
+                          (,alice-face erc-default-face)
+                          (,bob-face erc-nick-default-face)
+                          erc-default-face))
+     (erc-track-modified-channels)
+     (funcall assert-result `(5 ,alice-face erc-default-face))
+
+     ;; The mentioned user replies, mentioning the mentioner.  But
+     ;; instead of the normal "normals" processing preferring the ranked
+     ;; `erc-default-face', the `erc-nicks-track-faces' logic kicks in
+     ;; via `erc-track--alt-normals-function' and provides a `nicks'
+     ;; owned replacement.
+     (funcall set-faces `(erc-timestamp-face
+                          (,bob-face erc-default-face)
+                          (,alice-face erc-nick-default-face)
+                          erc-default-face))
+     (erc-track-modified-channels)
+     (funcall assert-result `(6 ,bob-face erc-default-face))
+
+     ;; Finally, another notice arrives.
+     (funcall set-faces '(erc-notice-face))
+     (erc-track-modified-channels)
+     (funcall assert-result '(7 . erc-notice-face)))))
+
+(ert-deftest erc-nicks-track-faces/defer ()
+  (should (eq erc-nicks-track-faces 'prioritize))
+  (let ((erc-nicks-track-faces 'defer))
+    (erc-nicks-tests--track-faces
+     (lambda (set-faces assert-result add-face bob-face alice-face)
+
+       (funcall add-face bob-face)
+       (funcall add-face alice-face)
+
+       ;; Simulate a JOIN.
+       (funcall set-faces '(erc-notice-face))
+       (erc-track-modified-channels)
+       (funcall assert-result '(1 . erc-notice-face))
+
+       ;; Someone speaks, and the mode-line indicator changes to the
+       ;; highest ranked face in the message.  (All `nicks' owned faces
+       ;; are unranked).
+       (funcall set-faces `(erc-timestamp-face
+                            (,bob-face erc-nick-default-face)
+                            erc-default-face))
+       (erc-track-modified-channels)
+       (funcall assert-result `(2 . erc-default-face))
+
+       ;; That same someone speaks, and the mode-line indicator changes
+       ;; to a `nicks' owned face.  It first reaches for the highest
+       ;; ranked face in the message but then applies the "normals"
+       ;; rules, resulting in a promoted alternate.
+       (funcall set-faces `(erc-timestamp-face
+                            (,bob-face erc-nick-default-face)
+                            erc-default-face))
+       (erc-track-modified-channels)
+       (funcall assert-result `(3 ,bob-face erc-nick-default-face))
+
+       ;; And yet again, which results in the indicator going back to one.
+       (funcall set-faces `(erc-timestamp-face
+                            (,bob-face erc-nick-default-face)
+                            erc-default-face))
+       (erc-track-modified-channels)
+       (funcall assert-result '(4 . erc-default-face))
+
+       ;; The same person mentions another server user, resulting in a
+       ;; change to that `nicks' owned face because the logic from
+       ;; 3. again applies.
+       (funcall set-faces `(erc-timestamp-face
+                            (,alice-face erc-default-face)
+                            (,bob-face erc-nick-default-face)
+                            erc-default-face))
+       (erc-track-modified-channels)
+       (funcall assert-result `(5 ,alice-face erc-default-face))
+
+       ;; The mentioned user replies, mentioning the mentioner.
+       ;; However, the `nicks' module does not intercede in the decision
+       ;; making to overrule the ranked nominee.
+       (funcall set-faces `(erc-timestamp-face
+                            (,bob-face erc-default-face)
+                            (,alice-face erc-nick-default-face)
+                            erc-default-face))
+       (erc-track-modified-channels)
+       (funcall assert-result '(6 . erc-default-face))
+
+       ;; Finally, another notice arrives.
+       (funcall set-faces '(erc-notice-face))
+       (erc-track-modified-channels)
+       (funcall assert-result '(7 . erc-notice-face))))))
+
+(ert-deftest erc-nicks-track-faces/nil ()
+  (should (eq erc-nicks-track-faces 'prioritize))
+  (let (erc-nicks-track-faces)
+    (erc-nicks-tests--track-faces
+     (lambda (set-faces assert-result _ bob-face alice-face)
+
+       (defvar erc-track--face-reject-function)
+       (should erc-track--face-reject-function)
+
+       ;; Simulate a JOIN.
+       (funcall set-faces '(erc-notice-face))
+       (erc-track-modified-channels)
+       (funcall assert-result '(1 . erc-notice-face))
+
+       ;; Someone speaks, and the mode-line indicator changes to the
+       ;; only ranked face in the message.
+       (funcall set-faces `(erc-timestamp-face
+                            (,bob-face erc-nick-default-face)
+                            erc-default-face))
+       (erc-track-modified-channels)
+       (funcall assert-result `(2 . erc-default-face))
+
+       ;; That same someone speaks, and since no other "normals" exist
+       ;; in the message, the indicator is not updated.
+       (funcall set-faces `(erc-timestamp-face
+                            (,bob-face erc-nick-default-face)
+                            erc-default-face))
+       (erc-track-modified-channels)
+       (funcall assert-result '(3 . erc-default-face))
+
+       ;; Now the same person mentions another server user, but the same
+       ;; logic applies, and the indicator is not updated.
+       (funcall set-faces `(erc-timestamp-face
+                            (,alice-face erc-default-face)
+                            (,bob-face erc-nick-default-face)
+                            erc-default-face))
+       (erc-track-modified-channels)
+       (funcall assert-result `(4 . erc-default-face))
+
+       ;; Finally, another notice arrives.
+       (funcall set-faces '(erc-notice-face))
+       (erc-track-modified-channels)
+       (funcall assert-result '(5 . erc-notice-face))))))
+
 ;;; erc-nicks-tests.el ends here
diff --git a/test/lisp/erc/erc-track-tests.el b/test/lisp/erc/erc-track-tests.el
index 8149138a971..c830c8b2016 100644
--- a/test/lisp/erc/erc-track-tests.el
+++ b/test/lisp/erc/erc-track-tests.el
@@ -227,6 +227,13 @@ erc-track-select-mode-line-face
 (defun erc-track-tests--select-mode-line-face (ranked normals cases)
   (setq normals (map-into (mapcar (lambda (f) (cons f t)) normals)
                           '(hash-table :test equal)))
+
+  (setq ranked (cons (map-into (mapcar (let ((i 0))
+                                         (lambda (f) (cons f (cl-incf i))))
+                                       ranked)
+                               '(hash-table :test equal))
+                     ranked))
+
   (pcase-dolist (`(,want ,cur-face ,new-faces) cases)
 
     (ert-info ((format "Observed: {cur: %S, new: %S, want: %S}"
@@ -235,8 +242,8 @@ erc-track-tests--select-mode-line-face
                              (mapcar (lambda (f) (cons f t)) new-faces)
                              '(hash-table :test equal))
                             (reverse new-faces)))
-      (should (equal want (funcall #'erc-track--select-mode-line-face
-                                   cur-face new-faces ranked normals))))))
+      (should (equal want (erc-track--select-mode-line-face
+                           cur-face new-faces ranked normals))))))
 
 ;; The main difference between these variants is that with the above,
 ;; when given alternating lines like
@@ -410,4 +417,255 @@ erc-track--collect-faces-in
     (when noninteractive
       (kill-buffer))))
 
+(defun erc-track-tests--modified-channels/baseline (set-faces)
+  ;; Simulate a JOIN, PART, etc. that's displayed in `erc-notice-face'.
+  (funcall set-faces '(erc-notice-face))
+  (erc-track-modified-channels)
+  (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                 '(1 . erc-notice-face)))
+
+  ;; Someone speaks, and the mode-line face goes from ERC's generic
+  ;; "notice" face, `erc-notice-face', to the first face in the
+  ;; inserted message that outranks it, which happens to be the
+  ;; `button' module's composite face for buttonized speakers:
+  ;; (erc-button-nick-default-face erc-nick-default-face).  It
+  ;; outranks both the previous occupant, `erc-notice-face', and its
+  ;; one cohabitant in the message text, `erc-default-face', in
+  ;; `erc-track-faces-priority-list'.  Note that in the following
+  ;; list, `erc-default-face' appears first because it's used for the
+  ;; opening speaker bracket "<".  The timestamp appears last because
+  ;; it's a right-sided stamp appended to the message body.
+  (funcall set-faces '(erc-timestamp-face
+                       (erc-button-nick-default-face erc-nick-default-face)
+                       erc-default-face))
+  (erc-track-modified-channels)
+  (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                 '(2 erc-button-nick-default-face erc-nick-default-face)))
+
+  ;; The speaker speaks again immediately, and the segment changes to
+  ;; `erc-default-face', which appears later in the message, as
+  ;; normal body text.  This happens because both `erc-default-face'
+  ;; and (erc-button-nick-default-face erc-nick-default-face) appear
+  ;; in `erc-track-faces-normal-list', meaning the lower-ranked
+  ;; former can replace the higher-ranked latter in the mode-line for
+  ;; the purpose of indicating channel activity.
+  (funcall set-faces '(erc-timestamp-face
+                       (erc-button-nick-default-face erc-nick-default-face)
+                       erc-default-face))
+  (erc-track-modified-channels)
+  (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                 '(3 . erc-default-face)))
+
+  ;; Note: if (erc-button-nick-default-face erc-nick-default-face)
+  ;; were removed from `erc-track-faces-priority-list' but kept in
+  ;; `erc-track-faces-normal-list', then replaying the sequence would
+  ;; result in the previous two results being switched:
+  ;; `erc-default-face' would replace `erc-notice-face' before being
+  ;; replaced by the buttonized composite.
+
+  ;; The speaker speaks yet again, and the segment goes back to the
+  ;; higher ranking face.
+  (funcall set-faces '(erc-timestamp-face
+                       (erc-button-nick-default-face erc-nick-default-face)
+                       erc-default-face))
+  (erc-track-modified-channels)
+  (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                 '(4 erc-button-nick-default-face erc-nick-default-face)))
+
+  ;; Finally, another notice arrives.  Although lower ranked, it also
+  ;; appears in `erc-track-faces-normal-list' and so is eligible to
+  ;; replace the incumbent.
+  (funcall set-faces '(erc-notice-face))
+  (erc-track-modified-channels)
+  (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                 '(5 . erc-notice-face))))
+
+(ert-deftest erc-track-modified-channels/baseline ()
+  (erc-tests-common-track-modified-channels
+   #'erc-track-tests--modified-channels/baseline))
+
+(ert-deftest erc-track-modified-channels/baseline/mention ()
+  (erc-tests-common-track-modified-channels
+   (lambda (set-faces)
+     ;; Note: these messages don't have timestamps.
+
+     ;; Simulate a JOIN, PART, etc. that's displayed in `erc-notice-face'.
+     (funcall set-faces '(erc-notice-face))
+     (erc-track-modified-channels)
+     (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                    '(1 . erc-notice-face)))
+
+     ;; Someone speaks, mentioning someone else, and the mode-line
+     ;; changes to (erc-button-nick-default-face erc-nick-default-face)
+     ;; rather than (erc-button-nick-default-face erc-default-face)
+     ;; based on their rankings in `erc-track-faces-priority-list'.
+     (funcall set-faces '((erc-button-nick-default-face erc-default-face)
+                          (erc-button-nick-default-face erc-nick-default-face)
+                          erc-default-face))
+     (erc-track-modified-channels)
+     (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                    '(2 erc-button-nick-default-face erc-nick-default-face)))
+
+     ;; Someone else speaks, again with a mention and additional body text.
+     (funcall set-faces '((erc-button-nick-default-face erc-default-face)
+                          (erc-button-nick-default-face erc-nick-default-face)
+                          erc-default-face))
+     (erc-track-modified-channels)
+     (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                    '(3 erc-button-nick-default-face erc-default-face)))
+
+     ;; And yet again, which results in the indicator going back to one.
+     (funcall set-faces '((erc-button-nick-default-face erc-default-face)
+                          (erc-button-nick-default-face erc-nick-default-face)
+                          erc-default-face))
+     (erc-track-modified-channels)
+     (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                    '(4 erc-button-nick-default-face erc-nick-default-face)))
+
+     ;; Finally, another notice arrives.
+     (funcall set-faces '(erc-notice-face))
+     (erc-track-modified-channels)
+     (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                    '(5 . erc-notice-face))))))
+
+;; The compat-oriented option `erc-track-ignore-normal-contenders-p'
+;; blinds track to `erc-track-faces-normal-list' for certain consecutive
+;; messages with an identical face makeup.
+(ert-deftest erc-track-modified-channels/baseline/ignore ()
+  (let ((erc-track-ignore-normal-contenders-p t))
+    (erc-tests-common-track-modified-channels
+     (lambda (set-faces)
+       ;; Simulate a JOIN, PART, etc. that's displayed in `erc-notice-face'.
+       (funcall set-faces '(erc-notice-face))
+       (erc-track-modified-channels)
+       (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                      '(1 . erc-notice-face)))
+
+       ;; Someone speaks, and the mode-line indicator's face changes to
+       ;; that of a buttonized speaker.
+       (funcall set-faces
+                '(erc-timestamp-face
+                  (erc-button-nick-default-face erc-nick-default-face)
+                  erc-default-face))
+       (erc-track-modified-channels)
+       (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                      '(2 erc-button-nick-default-face erc-nick-default-face)))
+
+       ;; The speaker speaks again immediately, and the segment doesn't
+       ;; change.
+       (funcall set-faces
+                '(erc-timestamp-face
+                  (erc-button-nick-default-face erc-nick-default-face)
+                  erc-default-face))
+       (erc-track-modified-channels)
+       (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                      '(3 erc-button-nick-default-face erc-nick-default-face)))
+
+       ;; Finally, another notice arrives.
+       (funcall set-faces '(erc-notice-face))
+       (erc-track-modified-channels)
+       (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                      '(4 . erc-notice-face)))))))
+
+;; Compat-oriented option `erc-track-ignore-normal-contenders-p'.
+(ert-deftest erc-track-modified-channels/baseline/mention/ignore ()
+  (let ((erc-track-ignore-normal-contenders-p t))
+    (erc-tests-common-track-modified-channels
+     (lambda (set-faces)
+
+       ;; Simulate a JOIN, PART, etc. that's displayed in `erc-notice-face'.
+       (funcall set-faces '(erc-notice-face))
+       (erc-track-modified-channels)
+       (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                      '(1 . erc-notice-face)))
+
+       ;; Someone speaks, and the mode-line indicator's face changes to
+       ;; that of a buttonized speaker.
+       (funcall set-faces
+                '((erc-button-nick-default-face erc-default-face)
+                  (erc-button-nick-default-face erc-nick-default-face)
+                  erc-default-face))
+       (erc-track-modified-channels)
+       (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                      '(2 erc-button-nick-default-face erc-nick-default-face)))
+
+       ;; Someone else speaks, again with a mention and additional body
+       ;; text, but the indicator stays the same.
+       (funcall set-faces
+                '((erc-button-nick-default-face erc-default-face)
+                  (erc-button-nick-default-face erc-nick-default-face)
+                  erc-default-face))
+       (erc-track-modified-channels)
+       (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                      '(3 erc-button-nick-default-face erc-nick-default-face)))
+
+       ;; Finally, another notice arrives.
+       (funcall set-faces '(erc-notice-face))
+       (erc-track-modified-channels)
+       (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                      '(4 . erc-notice-face)))))))
+
+;; Option `erc-track-priority-faces-only' does not affect the behavior
+;; of the baseline "normals" scenario because all faces appear in
+;; `erc-track-faces-priority-list'.
+(ert-deftest erc-track-modified-channels/priority-only-all/baseline ()
+  (let ((erc-track-priority-faces-only 'all))
+    (erc-tests-common-track-modified-channels
+     #'erc-track-tests--modified-channels/baseline)))
+
+;; This test simulates a common configuration that combines an
+;; `erc-track-faces-priority-list' removed of `erc-notice-face' with
+;; `erc-track-priority-faces-only' being `all'.  It also features in the
+;; sample configuration in ERC's manual.
+(ert-deftest erc-track-modified-channels/priority-only-all/sans-notice ()
+  (let ((erc-track-priority-faces-only 'all)
+        (erc-track-faces-priority-list
+         (remq 'erc-notice-face erc-track-faces-priority-list)))
+
+    (erc-tests-common-track-modified-channels
+     (lambda (set-faces)
+       ;; Note: these messages don't have timestamps.
+
+       ;; Simulate a message normally displayed in `erc-notice-face',
+       ;; which has been removed from `erc-track-faces-priority-list'.
+       (funcall set-faces '(erc-notice-face))
+       (erc-track-modified-channels)
+       (should-not (alist-get (current-buffer) erc-modified-channels-alist))
+
+       ;; Someone speaks, mentioning someone else, and the mode-line
+       ;; changes to the buttonized speaker face rather than the
+       ;; buttonized mention face, due to their respective ranks.
+       (funcall set-faces
+                '((erc-button-nick-default-face erc-default-face)
+                  (erc-button-nick-default-face erc-nick-default-face)
+                  erc-default-face))
+       (erc-track-modified-channels)
+       (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                      '(1 erc-button-nick-default-face erc-nick-default-face)))
+
+       ;; Someone else speaks, again with a mention and additional body text.
+       (funcall set-faces
+                '((erc-button-nick-default-face erc-default-face)
+                  (erc-button-nick-default-face erc-nick-default-face)
+                  erc-default-face))
+       (erc-track-modified-channels)
+       (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                      '(2 erc-button-nick-default-face erc-default-face)))
+
+       ;; And yet again, which results in the indicator going back to one.
+       (funcall set-faces
+                '((erc-button-nick-default-face erc-default-face)
+                  (erc-button-nick-default-face erc-nick-default-face)
+                  erc-default-face))
+       (erc-track-modified-channels)
+       (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                      '(3 erc-button-nick-default-face erc-nick-default-face)))
+
+       ;; Finally, another notice arrives, which is ignored.
+       (funcall set-faces '(erc-notice-face))
+       (erc-track-modified-channels)
+       (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                      '(3 erc-button-nick-default-face
+                          erc-nick-default-face)))))))
+
 ;;; erc-track-tests.el ends here
diff --git a/test/lisp/erc/resources/erc-tests-common.el b/test/lisp/erc/resources/erc-tests-common.el
index 1cd54a1f715..91654467dae 100644
--- a/test/lisp/erc/resources/erc-tests-common.el
+++ b/test/lisp/erc/resources/erc-tests-common.el
@@ -330,4 +330,47 @@ erc-tests-common-create-subprocess
     (set-process-query-on-exit-flag proc t)
     proc))
 
+(declare-function erc-track--setup "erc-track" ())
+
+(defun erc-tests-common-track-modified-channels (test)
+  (erc-tests-common-prep-for-insertion)
+  (setq erc--target (erc--target-from-string "#chan"))
+  (erc-tests-common-track-modified-channels-sans-setup test))
+
+(defun erc-tests-common-track-modified-channels-sans-setup (test)
+  "Provide a fixture for testing `erc-track-modified-channels'.
+Call function TEST with another function that sets the mocked return
+value of `erc-track--collect-faces-in' to the given argument, a list of
+faces in the reverse order they appear in an inserted message."
+  (defvar erc-modified-channels-alist)
+  (defvar erc-modified-channels-object)
+  (defvar erc-track--attn-faces)
+  (defvar erc-track--normal-faces)
+  (defvar erc-track--priority-faces)
+  (defvar erc-track-faces-normal-list)
+  (defvar erc-track-faces-priority-list)
+  (defvar erc-track-mode)
+
+  (cl-letf* ((erc-track-mode t)
+             (erc-modified-channels-alist nil)
+             (erc-modified-channels-object erc-modified-channels-object)
+             (faces ())
+             ((symbol-function 'force-mode-line-update) #'ignore)
+             ((symbol-function 'erc-faces-in) (lambda (_) faces))
+             ((symbol-function 'erc-track--collect-faces-in)
+              (lambda ()
+                (cons (map-into (mapcar (lambda (f) (cons f t)) faces)
+                                '(hash-table :test equal))
+                      faces))))
+    (erc-track--setup)
+
+    ;; Faces from `erc-track--attn-faces' prepended.
+    (should (= (+ (length erc-track--attn-faces)
+                  (length erc-track-faces-priority-list))
+               (hash-table-count erc-track--priority-faces)))
+    (should (= (length erc-track-faces-normal-list)
+               (hash-table-count erc-track--normal-faces)))
+
+    (funcall test (lambda (arg) (setq faces arg)))))
+
 (provide 'erc-tests-common)
-- 
2.46.1


^ permalink raw reply related	[flat|nested] 9+ messages in thread

* bug#67767: 30.0.50; ERC 5.6: Add track integration to the nicks module
       [not found] ` <87ed52q8rd.fsf@neverwas.me>
@ 2024-10-04  8:30   ` J.P.
       [not found]   ` <87ldz4b77j.fsf@neverwas.me>
  1 sibling, 0 replies; 9+ messages in thread
From: J.P. @ 2024-10-04  8:30 UTC (permalink / raw)
  To: 67767; +Cc: Trevor Arjeski, emacs-erc

[-- Attachment #1: Type: text/plain, Size: 1717 bytes --]

"J.P." <jp@neverwas.me> writes:

> It's been pointed out that the most recent attempt at improving the
> situation, especially with regard to the option `erc-nicks-track-faces',
> ended up perpetuating rather unintuitive aspects of the original
> behavior in certain common situations.
[...]
>
> Another problem with the current "normals" behavior is that it fails to
> adequately exhibit the "flickering" effect when `nicks' _isn't_ enabled.
> You can see this by connecting using the default configuration. Notice
> that the mode-line segment stays on `erc-default-face while users are
> conversing so long as they don't mention one another. However, the
> "normals" feature was always meant to provide more responsive feedback
> to clearly indicate active conversations (including monologuing). The
> patch tries to address this by adding the default buttonized speaker
> face to the related options `erc-track-faces-priority-list' and
> `erc-track-faces-normal-list'. If there's a smarter way, hopefully
> someone will speak up.

Attached is a v2 introducing a `t' choice for `erc-nicks-track-faces'.
It suppresses the "alternating" effect associated with the option
`erc-track-faces-normal-list'. See [1] for additional context.

This strays into new feature territory, which should be verboten for
patch releases. However, since closely related code exhibits bug-like
inconsistencies addressed by this patch, and such an addition might help
improve users' mental model in terms of predictability vis-a-vis the
current slate of related options, it seems a somewhat justifiable
inclusion (IMO). OTOH, we could just as well wait until 5.7.

[1] https://lists.gnu.org/archive/html/emacs-erc/2024-10/msg00006.html



[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #2: 0000-v1-v2.diff --]
[-- Type: text/x-patch, Size: 11069 bytes --]

From 417de6ebaf70fe4dfcf3cc03171f01e4c42a6d52 Mon Sep 17 00:00:00 2001
From: "F. Jason Park" <jp@neverwas.me>
Date: Fri, 4 Oct 2024 00:01:38 -0700
Subject: [PATCH 0/1] *** NOT A PATCH ***

v2. Add new `t' variant for `erc-nicks-track-faces', which suppresses the
"alternating" behavior associated with `erc-track-faces-normal-list'.
Refactor related aspects of erc-nicks.el to facilitate this.  Add supporting
test.

F. Jason Park (1):
  [5.6.1] Clarify behavior of erc-nicks-track-faces variants

 etc/ERC-NEWS                                |  13 +
 lisp/erc/erc-nicks.el                       |  89 +++++--
 lisp/erc/erc-track.el                       | 219 ++++++++++------
 test/lisp/erc/erc-nicks-tests.el            | 269 +++++++++++++++++++-
 test/lisp/erc/erc-track-tests.el            | 262 ++++++++++++++++++-
 test/lisp/erc/resources/erc-tests-common.el |  43 ++++
 6 files changed, 787 insertions(+), 108 deletions(-)

Interdiff:
diff --git a/etc/ERC-NEWS b/etc/ERC-NEWS
index d5df54256af..ea65a170b38 100644
--- a/etc/ERC-NEWS
+++ b/etc/ERC-NEWS
@@ -42,6 +42,12 @@ speaker names, with the latter option also gaining 'erc-notice-face'.
 This was done to provide a more frequent and practical indication of
 channel activity in keeping with the module's original design.
 
+** An arguably less distracting 'erc-nicks-track-faces' variant.
+Setting this option to t tells the 'track' module to have the mode-line
+indicator stick with the most recent speaker's face, even when they're
+monologuing, instead of alternating between it and the highest ranked
+'erc-track-faces-normal-list' member in a given message.
+
 \f
 * Changes in ERC 5.6
 
diff --git a/lisp/erc/erc-nicks.el b/lisp/erc/erc-nicks.el
index a17900d9330..3aed985ea21 100644
--- a/lisp/erc/erc-nicks.el
+++ b/lisp/erc/erc-nicks.el
@@ -175,17 +175,20 @@ erc-nicks-key-suffix-format
 
 (defcustom erc-nicks-track-faces 'prioritize
   "Show nick faces in the `track' module's portion of the mode line.
-A value of nil means don't show nick faces at all.  A value of
-`defer' means have `track' consider nick faces only after those
-ranked faces in `erc-track-faces-normal-list'.  This has the
-effect of \"alternating\" between a ranked \"normal\" and a nick.
-A value of `prioritize' works like `defer' when speakers stay the
-same but allows a new speaker's face to impersonate a ranked
-normal so nick faces can alternate back-to-back.  Like most
-options in this module, updating the value mid-session is not
-officially supported, although cycling \\[erc-nicks-mode] may be
-worth a shot."
-  :type '(choice (const nil) (const defer) (const prioritize)))
+A value of nil means don't show `nicks'-managed faces at all.  A value
+of t means treat them as non-\"normal\" faces ranked at or below
+`erc-default-face'.  This has the effect of always showing them while
+suppressing the \"alternating\" behavior normally associated with
+`erc-track-faces-normal-list' (including between the speaker and nicks
+mentioned in the message body.)  A value of `defer' means treat nicks as
+unranked normals to favor alternating between them and ranked normals.
+A value of `prioritize' exhibits the same alternating effect as `defer'
+when speakers stay the same but allows a new speaker's face to
+impersonate a ranked normal so that adjacent speakers alternate among
+themselves before deferring to non-face normals.  Like most options in
+this module, updating the value mid-session is not officially supported,
+although cycling \\[erc-nicks-mode] may be worth a shot."
+  :type '(choice boolean (const defer) (const prioritize)))
 
 (defvar erc-nicks--max-skip-search 3 ; make this an option?
   "Max number of faces to visit when testing `erc-nicks-skip-faces'.")
@@ -597,7 +600,9 @@ nicks
    (remove-function (local 'erc-button--modify-nick-function)
                     #'erc-nicks--highlight-button)
    (remove-function (local 'erc-track--alt-normals-function)
-                    #'erc-nicks--check-normals)
+                    #'erc-nicks--track-prioritize)
+   (remove-function (local 'erc-track--alt-normals-function)
+                    #'erc-nicks--track-always)
    (remove-hook 'erc-track-mode-hook #'erc-nicks--setup-track-integration t)
    (setf (alist-get "Edit face"
                     erc-button--nick-popup-alist nil 'remove #'equal)
@@ -726,7 +731,8 @@ erc-nicks--reject-uninterned-faces
     (setq candidate (cdr candidate)))
   (erc--solo candidate))
 
-(define-inline erc-nicks--oursp (face)
+(define-inline erc-nicks--ours-p (face)
+  "Return uninterned `nicks'-created face if FACE is a known list of faces."
   (inline-quote
    (and-let* ((sym (car-safe ,face))
               ((symbolp sym))
@@ -738,29 +744,43 @@ erc-nicks-track-normal-max-rank
 Must appear in both `erc-track-faces-priority-list' and
 `erc-track-faces-normal-list'.")
 
-(defun erc-nicks--check-normals (current contender contenders ranks normals)
-  "Return a viable non-CURRENT `nicks' face in CONTENDERS.
-But only do so if CURRENT and CONTENDER are \"normal\" faces either
-unranked or at or below `erc-nicks-track-normal-max-rank'.  See
-`erc-track--select-mode-line-face' for the expected types of CONTENDERS,
-RANKS, and NORMALS."
-  (and-let* (((or (null contender) (gethash contender normals)))
-             ((or (null current) (gethash current normals)))
-             (threshold (gethash erc-nicks-track-normal-max-rank (car ranks)))
-             ((<= threshold (or (gethash contender (car ranks))
-                                ;; Unranked `contender' always replaceable.
-                                most-positive-fixnum)))
-             (spkr (or (erc-nicks--oursp current)
-                       ;; Use t to mean `current' is not a nick face but
-                       ;; replaceable nonetheless.
-                       (null current)
-                       (<= threshold (or (gethash current (car ranks)) 0)))))
+(defun erc-nicks--assess-track-faces (current contender ranks normals)
+  "Return symbol face for CURRENT or t, to mean CURRENT is replaceable.
+But only do so if CURRENT and CONTENDER are either nil or \"normal\"
+faces ranking at or below `erc-nicks-track-normal-max-rank'.  See
+`erc-track--select-mode-line-face' for the expected types of RANKS and
+NORMALS.  Expect a non-nil CONTENDER to always be ranked."
+  (and-let*
+      (((or (null contender) (gethash contender normals)))
+       ((or (null current) (gethash current normals)))
+       (threshold (gethash erc-nicks-track-normal-max-rank (car ranks)))
+       ((or (null contender) (<= threshold (gethash contender (car ranks)))))
+       ((or (erc-nicks--ours-p current)
+            (null current)
+            (<= threshold (or (gethash current (car ranks)) 0)))))))
+
+(defun erc-nicks--track-prioritize (current contender contenders ranks normals)
+  "Return a viable non-CURRENT `nicks' face among CONTENDERS.
+See `erc-track--select-mode-line-face' for parameter types."
+  (when-let
+      ((spkr (erc-nicks--assess-track-faces current contender ranks normals)))
     (catch 'contender
       (dolist (candidate (cdr contenders))
         (when-let (((not (equal candidate current)))
-                   ((gethash candidate normals))
-                   (s (erc-nicks--oursp candidate))
+                   (s (erc-nicks--ours-p candidate))
                    ((not (eq s spkr))))
+          (cl-assert (gethash candidate normals))
+          (throw 'contender candidate))))))
+
+(defun erc-nicks--track-always (current contender contenders ranks normals)
+  "Return a viable `nicks' face, possibly CURRENT, among CONTENDERS.
+See `erc-track--select-mode-line-face' for parameter types."
+  (when-let
+      ((spkr (erc-nicks--assess-track-faces current contender ranks normals)))
+    (catch 'contender
+      (dolist (candidate (cdr (reverse contenders)))
+        (when (erc-nicks--ours-p candidate)
+          (cl-assert (gethash candidate normals))
           (throw 'contender candidate))))))
 
 (defun erc-nicks--setup-track-integration ()
@@ -770,7 +790,10 @@ erc-nicks--setup-track-integration
       ;; Variant `defer' is handled elsewhere.
       ('prioritize
        (add-function :override (local 'erc-track--alt-normals-function)
-                     #'erc-nicks--check-normals))
+                     #'erc-nicks--track-prioritize))
+      ((or 't 'always)
+       (add-function :override (local 'erc-track--alt-normals-function)
+                     #'erc-nicks--track-always))
       ('nil
        (add-function :override (local 'erc-track--face-reject-function)
                      #'erc-nicks--reject-uninterned-faces)))))
diff --git a/test/lisp/erc/erc-nicks-tests.el b/test/lisp/erc/erc-nicks-tests.el
index 75cb98b8407..c865a902a0e 100644
--- a/test/lisp/erc/erc-nicks-tests.el
+++ b/test/lisp/erc/erc-nicks-tests.el
@@ -788,4 +788,51 @@ erc-nicks-track-faces/nil
        (erc-track-modified-channels)
        (funcall assert-result '(5 . erc-notice-face))))))
 
+(ert-deftest erc-nicks-track-faces/t ()
+  (should (eq erc-nicks-track-faces 'prioritize))
+  (let ((erc-nicks-track-faces t))
+    (erc-nicks-tests--track-faces
+     (lambda (set-faces assert-result add-face bob-face alice-face)
+
+       (defvar erc-track--alt-normals-function)
+       (should erc-track--alt-normals-function)
+
+       (funcall add-face bob-face)
+       (funcall add-face alice-face)
+
+       ;; Simulate a JOIN.
+       (funcall set-faces '(erc-notice-face))
+       (erc-track-modified-channels)
+       (funcall assert-result '(1 . erc-notice-face))
+
+       ;; Someone speaks, and the mode-line indicator changes to that
+       ;; someone's `nicks'-owned face.
+       (funcall set-faces `(erc-timestamp-face
+                            (,bob-face erc-nick-default-face)
+                            erc-default-face))
+       (erc-track-modified-channels)
+       (funcall assert-result `(2 ,bob-face erc-nick-default-face))
+
+       ;; That same someone speaks, and though one other "normal" exists
+       ;; in the message, `erc-default-face', no update occurs.
+       (funcall set-faces `(erc-timestamp-face
+                            (,bob-face erc-nick-default-face)
+                            erc-default-face))
+       (erc-track-modified-channels)
+       (funcall assert-result `(3 ,bob-face erc-nick-default-face))
+
+       ;; Another server user speaks, mentioning the previous speaker,
+       ;; and the indicator is updated to reflect the new speaker.
+       (funcall set-faces `(erc-timestamp-face
+                            (,bob-face erc-default-face) ; bob:
+                            (,alice-face erc-nick-default-face) ; <alice>
+                            erc-default-face))
+       (erc-track-modified-channels)
+       (funcall assert-result `(4 ,alice-face erc-nick-default-face))
+
+       ;; Finally, another notice arrives.
+       (funcall set-faces '(erc-notice-face))
+       (erc-track-modified-channels)
+       (funcall assert-result '(5 . erc-notice-face))))))
+
 ;;; erc-nicks-tests.el ends here
-- 
2.46.2


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From 417de6ebaf70fe4dfcf3cc03171f01e4c42a6d52 Mon Sep 17 00:00:00 2001
From: "F. Jason Park" <jp@neverwas.me>
Date: Thu, 26 Sep 2024 21:34:25 -0700
Subject: [PATCH 1/1] [5.6.1] Clarify behavior of erc-nicks-track-faces
 variants

* etc/ERC-NEWS: Mention changes to `erc-track-faces-normal-list'
and `erc-track-faces-priority-list'.  Also mention new choice variant
for option `erc-nicks-track-faces'.
* lisp/erc/erc-nicks.el (erc-nicks-track-faces): Update doc, and
introduce new `t' value choice.
(erc-nicks-mode, erc-nicks-disable): Update removals from
`erc-track--alt-normals-function' to reflect recent refactoring.
(erc-nicks--reject-uninterned-faces): Use helper.
(erc-nicks--oursp, erc-nicks--ours-p): Rename former to latter to
respect project style guidelines regarding predicates.
(erc-nicks-track-normal-max-rank): New variable.
(erc-nicks--check-normals, erc-nicks--assess-track-faces): Rename former
to latter and change purpose to checking for "normals" membership, ranks
position, and incumbent face ownership.  Remove unused CONTENDERS
parameter.  Also change behavior to consider replacing the current
mode-line face when it's not `nicks' owned if it's explicitly ranked
lower than `erc-default-face'.
(erc-nicks--track-prioritize, erc-nicks--track-always): New
complementary functions implementing the t and `prioritize' variants of
`erc-nicks-track-faces'.  Both make use of the factored-out
`erc-nicks--check-normals' logic.
(erc-nicks--setup-track-integration): Add `erc-nicks--track-always' to
`erc-track--alt-normals-function' when `erc-track-normal-faces' is t.
* lisp/erc/erc-track.el (erc-track--massage-nick-button-faces): Change
type of symbol property `erc-track--obsolete-faces' for options
`erc-track-faces-priority-list' and friends from a boolean to an alist.
(erc-track-faces-priority-list): Add new face for buttonized speakers.
(erc-track-faces-normal-list): Add new face for buttonized speakers.
Also add `erc-notice-face'.
(erc-track--priority-faces): New local variable to cache ranked faces.
(erc-track--setup): Initialize new `erc-track--priority-faces' variable
and refactor.
(erc-track--alt-normals-function): Doc.
(erc-track--select-mode-line-face): Update expected type of `ranks'
parameter.
(erc-track-modified-channels): Fix wrong-type bug occurring when
`erc-track-ignore-normal-contenders-p' and
`erc-track-priority-faces-only' are both non-nil.  Also fix subtle
compatibility oversight regarding an empty face list returned by
`erc-track--collect-faces-in'.
* test/lisp/erc/erc-nicks-tests.el: Load helpers and fixtures library.
(erc-nicks-tests--track-faces): New function.
(erc-nicks-track-faces/prioritize, erc-nicks-track-faces/defer)
(erc-nicks-track-faces/nil, erc-nicks-track-faces/t): New tests.
* test/lisp/erc/erc-track-tests.el
(erc-track-tests--select-mode-line-face): Update expected type of mocked
parameter.
(erc-track-tests--modified-channels/baseline): New function.
(erc-track-modified-channels/baseline)
(erc-track-modified-channels/baseline/mention)
(erc-track-modified-channels/baseline/ignore)
(erc-track-modified-channels/baseline/mention/ignore)
(erc-track-modified-channels/priority-only-all/baseline)
(erc-track-modified-channels/priority-only-all/sans-notice): New tests.
* test/lisp/erc/resources/erc-tests-common.el
(erc-tests-common-track-modified-channels)
(erc-tests-common-track-modified-channels-sans-setup): New functions.
(Bug67767)
---
 etc/ERC-NEWS                                |  13 +
 lisp/erc/erc-nicks.el                       |  89 +++++--
 lisp/erc/erc-track.el                       | 219 ++++++++++------
 test/lisp/erc/erc-nicks-tests.el            | 269 +++++++++++++++++++-
 test/lisp/erc/erc-track-tests.el            | 262 ++++++++++++++++++-
 test/lisp/erc/resources/erc-tests-common.el |  43 ++++
 6 files changed, 787 insertions(+), 108 deletions(-)

diff --git a/etc/ERC-NEWS b/etc/ERC-NEWS
index b267db5502e..ea65a170b38 100644
--- a/etc/ERC-NEWS
+++ b/etc/ERC-NEWS
@@ -35,6 +35,19 @@ has been removed.
 Option 'erc-keep-place-indicator-truncation' manages the tension between
 truncation and place keeping, prioritizing one or the other.
 
+** Updated defaults for the 'track' module's face-list options.
+The default values of options 'erc-track-faces-priority-list' and
+'erc-track-faces-normal-list' have both gained a face for buttonized
+speaker names, with the latter option also gaining 'erc-notice-face'.
+This was done to provide a more frequent and practical indication of
+channel activity in keeping with the module's original design.
+
+** An arguably less distracting 'erc-nicks-track-faces' variant.
+Setting this option to t tells the 'track' module to have the mode-line
+indicator stick with the most recent speaker's face, even when they're
+monologuing, instead of alternating between it and the highest ranked
+'erc-track-faces-normal-list' member in a given message.
+
 \f
 * Changes in ERC 5.6
 
diff --git a/lisp/erc/erc-nicks.el b/lisp/erc/erc-nicks.el
index a0d6d17d732..3aed985ea21 100644
--- a/lisp/erc/erc-nicks.el
+++ b/lisp/erc/erc-nicks.el
@@ -175,17 +175,20 @@ erc-nicks-key-suffix-format
 
 (defcustom erc-nicks-track-faces 'prioritize
   "Show nick faces in the `track' module's portion of the mode line.
-A value of nil means don't show nick faces at all.  A value of
-`defer' means have `track' consider nick faces only after those
-ranked faces in `erc-track-faces-normal-list'.  This has the
-effect of \"alternating\" between a ranked \"normal\" and a nick.
-The value `prioritize' means have `track' consider nick faces to
-be \"normal\" unless the current speaker is the same as the
-previous one, in which case pretend the value is `defer'.  Like
-most options in this module, updating the value mid-session is
-not officially supported, although cycling \\[erc-nicks-mode] may
-be worth a shot."
-  :type '(choice (const nil) (const defer) (const prioritize)))
+A value of nil means don't show `nicks'-managed faces at all.  A value
+of t means treat them as non-\"normal\" faces ranked at or below
+`erc-default-face'.  This has the effect of always showing them while
+suppressing the \"alternating\" behavior normally associated with
+`erc-track-faces-normal-list' (including between the speaker and nicks
+mentioned in the message body.)  A value of `defer' means treat nicks as
+unranked normals to favor alternating between them and ranked normals.
+A value of `prioritize' exhibits the same alternating effect as `defer'
+when speakers stay the same but allows a new speaker's face to
+impersonate a ranked normal so that adjacent speakers alternate among
+themselves before deferring to non-face normals.  Like most options in
+this module, updating the value mid-session is not officially supported,
+although cycling \\[erc-nicks-mode] may be worth a shot."
+  :type '(choice boolean (const defer) (const prioritize)))
 
 (defvar erc-nicks--max-skip-search 3 ; make this an option?
   "Max number of faces to visit when testing `erc-nicks-skip-faces'.")
@@ -597,7 +600,9 @@ nicks
    (remove-function (local 'erc-button--modify-nick-function)
                     #'erc-nicks--highlight-button)
    (remove-function (local 'erc-track--alt-normals-function)
-                    #'erc-nicks--check-normals)
+                    #'erc-nicks--track-prioritize)
+   (remove-function (local 'erc-track--alt-normals-function)
+                    #'erc-nicks--track-always)
    (remove-hook 'erc-track-mode-hook #'erc-nicks--setup-track-integration t)
    (setf (alist-get "Edit face"
                     erc-button--nick-popup-alist nil 'remove #'equal)
@@ -724,29 +729,58 @@ erc-nicks--reject-uninterned-faces
               ((facep next))
               ((not (intern-soft next))))
     (setq candidate (cdr candidate)))
-  (if (and (consp candidate) (not (cdr candidate))) (car candidate) candidate))
+  (erc--solo candidate))
 
-(define-inline erc-nicks--oursp (face)
+(define-inline erc-nicks--ours-p (face)
+  "Return uninterned `nicks'-created face if FACE is a known list of faces."
   (inline-quote
    (and-let* ((sym (car-safe ,face))
               ((symbolp sym))
               ((get sym 'erc-nicks--key)))
      sym)))
 
-(defun erc-nicks--check-normals (current contender contenders normals)
-  "Return a viable `nicks'-owned face from NORMALS in CONTENDERS.
-But only do so if the CURRENT face is also one of ours and in
-NORMALS and if the highest ranked CONTENDER among new faces is
-`erc-default-face'."
-  (and-let* (((eq contender 'erc-default-face))
-             ((or (null current) (gethash current normals)))
-             (spkr (or (null current) (erc-nicks--oursp current))))
+(defvar erc-nicks-track-normal-max-rank 'erc-default-face
+  "Highest priority normal face still eligible to alternate with `nicks' faces.
+Must appear in both `erc-track-faces-priority-list' and
+`erc-track-faces-normal-list'.")
+
+(defun erc-nicks--assess-track-faces (current contender ranks normals)
+  "Return symbol face for CURRENT or t, to mean CURRENT is replaceable.
+But only do so if CURRENT and CONTENDER are either nil or \"normal\"
+faces ranking at or below `erc-nicks-track-normal-max-rank'.  See
+`erc-track--select-mode-line-face' for the expected types of RANKS and
+NORMALS.  Expect a non-nil CONTENDER to always be ranked."
+  (and-let*
+      (((or (null contender) (gethash contender normals)))
+       ((or (null current) (gethash current normals)))
+       (threshold (gethash erc-nicks-track-normal-max-rank (car ranks)))
+       ((or (null contender) (<= threshold (gethash contender (car ranks)))))
+       ((or (erc-nicks--ours-p current)
+            (null current)
+            (<= threshold (or (gethash current (car ranks)) 0)))))))
+
+(defun erc-nicks--track-prioritize (current contender contenders ranks normals)
+  "Return a viable non-CURRENT `nicks' face among CONTENDERS.
+See `erc-track--select-mode-line-face' for parameter types."
+  (when-let
+      ((spkr (erc-nicks--assess-track-faces current contender ranks normals)))
     (catch 'contender
-      (dolist (candidate (cdr contenders) contender)
+      (dolist (candidate (cdr contenders))
         (when-let (((not (equal candidate current)))
-                   ((gethash candidate normals))
-                   (s (erc-nicks--oursp candidate))
+                   (s (erc-nicks--ours-p candidate))
                    ((not (eq s spkr))))
+          (cl-assert (gethash candidate normals))
+          (throw 'contender candidate))))))
+
+(defun erc-nicks--track-always (current contender contenders ranks normals)
+  "Return a viable `nicks' face, possibly CURRENT, among CONTENDERS.
+See `erc-track--select-mode-line-face' for parameter types."
+  (when-let
+      ((spkr (erc-nicks--assess-track-faces current contender ranks normals)))
+    (catch 'contender
+      (dolist (candidate (cdr (reverse contenders)))
+        (when (erc-nicks--ours-p candidate)
+          (cl-assert (gethash candidate normals))
           (throw 'contender candidate))))))
 
 (defun erc-nicks--setup-track-integration ()
@@ -756,7 +790,10 @@ erc-nicks--setup-track-integration
       ;; Variant `defer' is handled elsewhere.
       ('prioritize
        (add-function :override (local 'erc-track--alt-normals-function)
-                     #'erc-nicks--check-normals))
+                     #'erc-nicks--track-prioritize))
+      ((or 't 'always)
+       (add-function :override (local 'erc-track--alt-normals-function)
+                     #'erc-nicks--track-always))
       ('nil
        (add-function :override (local 'erc-track--face-reject-function)
                      #'erc-nicks--reject-uninterned-faces)))))
diff --git a/lisp/erc/erc-track.el b/lisp/erc/erc-track.el
index f40960e4a22..82e5f402910 100644
--- a/lisp/erc/erc-track.el
+++ b/lisp/erc/erc-track.el
@@ -161,25 +161,33 @@ erc-track-use-faces
 \(e.g. `erc-pal-face' is used if a pal sent a message to that channel.)"
   :type 'boolean)
 
+;; In an emergency, users can opt out of this migration with:
+;;
+;;   (put 'erc-track-faces-priority-list 'erc-track--obsolete-faces t)
+;;   (put 'erc-track-faces-normal-list 'erc-track--obsolete-faces t)
+;;
 (defun erc-track--massage-nick-button-faces (sym val &optional set-fn)
-  "Transform VAL of face-list option SYM to have new defaults.
-Use `set'-compatible SET-FN when given.  If an update was
-performed, set the symbol property `erc-track--obsolete-faces' of
-SYM to t."
-  (let* ((changedp nil)
-         (new (mapcar
-               (lambda (f)
-                 (if (and (eq (car-safe f) 'erc-nick-default-face)
-                          (equal f '(erc-nick-default-face erc-default-face)))
-                     (progn
-                       (setq changedp t)
-                       (put sym 'erc-track--obsolete-faces t)
-                       (cons 'erc-button-nick-default-face (cdr f)))
-                   f))
-               val)))
-    (if set-fn
-        (funcall set-fn sym (if changedp new val))
-      (set-default sym (if changedp new val)))))
+  "Transform VAL of face-list option SYM to remove/replace obsolete items.
+Use `set'-compatible SET-FN when given.  Record any migrations as cons
+cells of (OLD . NEW) in the symbol property `erc-track--obsolete-faces'
+of SYM."
+  (let* ((oldface '(erc-nick-default-face erc-default-face))
+         (newface '(erc-button-nick-default-face erc-default-face))
+         (migrations (get sym 'erc-track--obsolete-faces))
+         (new (if migrations
+                  val
+                (delq nil
+                      (mapcar
+                       (lambda (f)
+                         (if (equal f oldface)
+                             (setf (alist-get oldface migrations
+                                              nil nil #'equal)
+                                   (and (not (member newface val)) newface))
+                           f))
+                       val)))))
+    (when migrations
+      (put sym 'erc-track--obsolete-faces migrations))
+    (if set-fn (funcall set-fn sym new) (set-default sym new))))
 
 (defcustom erc-track-faces-priority-list
   '(erc-error-face
@@ -191,6 +199,7 @@ erc-track-faces-priority-list
     (erc-button erc-default-face)
     erc-dangerous-host-face
     erc-nick-default-face
+    (erc-button-nick-default-face erc-nick-default-face)
     (erc-button-nick-default-face erc-default-face)
     erc-default-face
     erc-action-face
@@ -204,7 +213,7 @@ erc-track-faces-priority-list
 
 Note that ERC prioritizes certain faces reserved for critical
 messages regardless of this option's value."
-  :package-version '(ERC . "5.6")
+  :package-version '(ERC . "5.6.1")
   :set #'erc-track--massage-nick-button-faces
   :type (erc--with-dependent-type-match
          (repeat (choice face (repeat :tag "Combination" face)))
@@ -229,8 +238,10 @@ erc-track-faces-normal-list
   '((erc-button erc-default-face)
     erc-dangerous-host-face
     erc-nick-default-face
+    (erc-button-nick-default-face erc-nick-default-face)
     (erc-button-nick-default-face erc-default-face)
     erc-default-face
+    erc-notice-face
     erc-action-face)
   "A list of faces considered to be part of normal conversations.
 This list is used to highlight active buffer names in the mode line.
@@ -246,7 +257,7 @@ erc-track-faces-normal-list
 \\[erc-track-mode].
 
 The effect may be disabled by setting this variable to nil."
-  :package-version '(ERC . "5.6")
+  :package-version '(ERC . "5.6.1")
   :set #'erc-track--massage-nick-button-faces
   :type (erc--with-dependent-type-match
          (repeat (choice face (repeat :tag "Combination" face)))
@@ -636,49 +647,79 @@ erc-track-when-inactive
 	       (erc-track-enable))
 	   (set sym val))))
 
+(defvar-local erc-track--priority-faces nil
+  "Local copy of `erc-track-faces-priority-list' as a hash table.
+Keys are faces and values are rank integers (smaller is more important).")
+
 (defvar-local erc-track--normal-faces nil
-  "Local copy of `erc-track-faces-normal-list' as a hash table.")
+  "Local copy of `erc-track-faces-normal-list' as a hash table.
+Keys and values are faces.  The table is weak valued so it can double as
+a buttonizing cache.  See `erc-button-add-button' and `erc--merge-prop'.")
 
 (defun erc-track--setup ()
   "Initialize a buffer for use with the `track' module.
-If this is a server buffer or `erc-track-faces-normal-list' is
-locally bound, create a new `erc-track--normal-faces' for the
-current buffer.  Otherwise, set the local value to the server
-buffer's."
+If this is a server buffer or either `erc-track-faces-normal-list' or
+`erc-track-faces-priority-list' is locally bound, create a new cache
+table with corresponding local variable `erc-track--normal-faces' or
+`erc-track--priority-faces'.  Otherwise, in target buffers with no local
+binding, set the cache variable's local value to that of server's."
   (if erc-track-mode
-      (let ((existing (erc-with-server-buffer erc-track--normal-faces))
-            (localp (and erc--target
-                         (local-variable-p 'erc-track-faces-normal-list)))
-            (opts '(erc-track-faces-normal-list erc-track-faces-priority-list))
-            warnp table)
+      (let (warnp)
         ;; Don't bother warning users who've disabled `button'.
-        (unless (or erc--target (not (or (bound-and-true-p erc-button-mode)
-                                         (memq 'button erc-modules))))
-          (when (or localp (local-variable-p 'erc-track-faces-priority-list))
-            (dolist (opt opts)
+        (unless (or erc--target
+                    (not (or (bound-and-true-p erc-button-mode)
+                             (memq 'button erc-modules))))
+          (dolist (opt '(erc-track-faces-normal-list
+                         erc-track-faces-priority-list))
+            (when (local-variable-p opt)
               (erc-track--massage-nick-button-faces opt (symbol-value opt)
-                                                    #'set)))
-          (dolist (opt opts)
-            (when (get opt 'erc-track--obsolete-faces)
-              (push opt warnp)
+                                                    #'set))
+            (when-let ((migrations (get opt 'erc-track--obsolete-faces))
+                       ((consp migrations)))
+              (push (cons opt
+                          (mapcar (pcase-lambda (`(,old . ,new))
+                                    (format (if new "changed %s to %s"
+                                              "removed %s")
+                                            old new))
+                                  migrations))
+                    warnp)
               (put opt 'erc-track--obsolete-faces nil)))
           (when warnp
-            (erc--warn-once-before-connect 'erc-track-mode
-              (if (cdr warnp) "Options " "Option ")
-              (mapconcat (lambda (o) (format "`%S'" o)) warnp " and ")
-              (if (cdr warnp) " contain" " contains")
-              " an obsolete item, %S, intended to match buttonized nicknames."
-              " ERC has changed it to %S for the current session."
-              " Please save the current value to silence this message."
-              '(erc-nick-default-face erc-default-face)
-              '(erc-button-nick-default-face erc-default-face))))
-        (when (or (null existing) localp)
-          (setq table (map-into (mapcar (lambda (f) (cons f f))
-                                        erc-track-faces-normal-list)
-                                '(hash-table :test equal :weakness value))))
-        (setq erc-track--normal-faces (or table existing))
-        (unless (or localp existing)
-          (erc-with-server-buffer (setq erc-track--normal-faces table))))
+            (pcase-dolist (`(,opt . ,migrations) warnp)
+              (erc--warn-once-before-connect 'erc-track-mode
+                "Option `%S' contains "
+                (if (cdr migrations) "obsolete items." "an obsolete item.")
+                " ERC has done the following for the current session: %s."
+                " Please review these changes and, if convinced,"
+                " silence this message by saving the current value."
+                opt (string-join migrations ", ")))))
+        ;; Set `erc-track--priority-faces' cache to new or shared value.
+        (let* ((localp (and erc--target
+                            (local-variable-p 'erc-track-faces-priority-list)))
+               (existing (erc-with-server-buffer erc-track--priority-faces))
+               (table (or (and (not localp) existing)
+                          (let ((p 0))
+                            (map-into
+                             (mapcar (lambda (f) (cons f (cl-incf p)))
+                                     (append erc-track--attn-faces
+                                             erc-track-faces-priority-list))
+                             `(hash-table :test equal))))))
+          (setq erc-track--priority-faces table)
+          (unless (or localp existing)
+            (erc-with-server-buffer (setq erc-track--priority-faces table))))
+        ;; Likewise for `erc-track--normal-faces' cache.
+        (let* ((localp (and erc--target
+                            (local-variable-p 'erc-track-faces-normal-list)))
+               (existing (erc-with-server-buffer erc-track--normal-faces))
+               (table (or (and (not localp) existing)
+                          (map-into (mapcar (lambda (f) (cons f f))
+                                            erc-track-faces-normal-list)
+                                    `(hash-table :test equal
+                                                 :weakness value)))))
+          (setq erc-track--normal-faces table)
+          (unless (or localp existing)
+            (erc-with-server-buffer (setq erc-track--normal-faces table)))))
+    (kill-local-variable 'erc-track--priority-faces)
     (kill-local-variable 'erc-track--normal-faces)))
 
 ;;; Visibility
@@ -915,44 +956,54 @@ erc-track-select-mode-line-face
 (defvar erc-track--alt-normals-function nil
   "A function to possibly elect a \"normal\" face.
 Called with the current incumbent and the worthiest new contender
-followed by all new contending faces and so-called \"normal\"
-faces.  See `erc-track--select-mode-line-face' for their meanings
-and expected types.  This function should return a face or nil.")
+followed by all new contending faces, ranked faces, and so-called
+\"normal\" faces.  See `erc-track--select-mode-line-face' for their
+meanings and expected types.  This function should return a face or nil.")
 
 (defun erc-track--select-mode-line-face (cur-face new-faces ranks normals)
   "Return CUR-FACE or a replacement for displaying in the mode-line, or nil.
-Expect RANKS to be a list of faces and both NORMALS and the car
-of NEW-FACES to be hash tables mapping faces to non-nil values.
-Assume the latter's makeup and that of RANKS to resemble
-`erc-track-faces-normal-list' and `erc-track-faces-priority-list'.
-If NEW-FACES has a cdr, expect it to be its car's contents
-ordered from most recently seen (later in the buffer) to
-earliest.  In general, act like `erc-track-select-mode-line-face'
-except appeal to `erc-track--alt-normals-function' if it's
-non-nil, falling back on reconsidering NEW-FACES when CUR-FACE
-outranks all its members.  That is, choose the first among RANKS
-in NEW-FACES not equal to CUR-FACE.  Failing that, choose the
-first face in NEW-FACES that's also in NORMALS, assuming
-NEW-FACES has a cdr."
+Expect NEW-FACES to be a cons cell whose car is a hash table mapping
+faces present in the applicable region to t and whose cdr is its car's
+contents ordered from most recently seen (later in the buffer) to
+earliest.  Expect RANKS to be a cons cell whose car is a hash table
+similar to `erc-track--priority-faces' and whose cdr is a list of
+prioritized faces resembling `erc-track-faces-priority-list'.  Expect
+NORMALS to be a hash table mapping faces to themselves.  In general, act
+identically to `erc-track-select-mode-line-face', except appeal to
+`erc-track--alt-normals-function' if it's non-nil, and fall back on
+reconsidering only NEW-FACES appearing in NORMALS when CUR-FACE is
+itself \"normal\" and outranks all NEW-FACES.  That is, choose the first
+among RANKS in both NEW-FACES and NORMALS not equal to CUR-FACE.
+Failing that, choose the first face in both NEW-FACES and NORMALS."
   (cl-check-type erc-track-ignore-normal-contenders-p null)
   (cl-check-type new-faces cons)
+  ;; Choose the highest ranked face in `erc-track-faces-priority-list'
+  ;; that's either `cur-face' itself or one appearing in the region
+  ;; being processed.
   (when-let ((choice (catch 'face
-                       (dolist (candidate ranks)
+                       (dolist (candidate (cdr ranks))
                          (when (or (equal candidate cur-face)
                                    (gethash candidate (car new-faces)))
                            (throw 'face candidate))))))
     (or (and erc-track--alt-normals-function
              (funcall erc-track--alt-normals-function
-                      cur-face choice new-faces normals))
+                      cur-face choice new-faces ranks normals))
+        ;; If `choice' is still `cur-face' and also a "normal", attempt
+        ;; to choose another normal in order to produce the flickering
+        ;; effect mentioned in the doc of `erc-track-faces-normal-list'.
         (and (equal choice cur-face)
              (gethash choice normals)
              (catch 'face
+               ;; If ranked "normal" faces other than `choice' appear in
+               ;; the region, return the most important one.
                (progn
-                 (dolist (candidate ranks)
+                 (dolist (candidate (cdr ranks))
                    (when (and (not (equal candidate choice))
                               (gethash candidate (car new-faces))
                               (gethash choice normals))
                      (throw 'face candidate)))
+                 ;; Otherwise, go with any "normal" face other than
+                 ;; `choice' in the region.
                  (dolist (candidate (cdr new-faces))
                    (when (and (not (equal candidate choice))
                               (gethash candidate normals))
@@ -996,14 +1047,24 @@ erc-track-modified-channels
              (normals erc-track--normal-faces)
              (erc-track-faces-priority-list
               `(,@erc-track--attn-faces ,@erc-track-faces-priority-list))
-             (ranks erc-track-faces-priority-list)
+             (ranks (cons erc-track--priority-faces
+                          erc-track-faces-priority-list))
              ((not (and
                     (or (eq erc-track-priority-faces-only 'all)
                         (member this-channel erc-track-priority-faces-only))
-                    (not (catch 'found
-                           (dolist (f ranks)
-                             (when (gethash f (or (car-safe faces) faces))
-                               (throw 'found t)))))))))
+                    ;; Iterate over the shorter of `ranks' and `faces'.
+                    (let* ((r>fp (or erc-track-ignore-normal-contenders-p
+                                     (> (hash-table-count (car ranks))
+                                        (hash-table-count (car faces)))))
+                           (elems (cond ((not r>fp) (cdr ranks)) ; f>=r
+                                        (erc-track-ignore-normal-contenders-p
+                                         faces)
+                                        ((cdr faces))))
+                           (table (if r>fp (car ranks) (car faces))))
+                      (not (catch 'found
+                             (dolist (f elems)
+                               (when (gethash f table)
+                                 (throw 'found t))))))))))
           (progn ; FIXME remove `progn' on next major edit
 	    (if (not (assq (current-buffer) erc-modified-channels-alist))
 		;; Add buffer, faces and counts
@@ -1017,7 +1078,7 @@ erc-track-modified-channels
                                         nil faces ranks normals))))
 			    erc-modified-channels-alist))
 	      ;; Else modify the face for the buffer, if necessary.
-	      (when faces
+              (when (or erc-track-ignore-normal-contenders-p (cdr faces))
 		(let* ((cell (assq (current-buffer)
 				   erc-modified-channels-alist))
 		       (old-face (cddr cell))
diff --git a/test/lisp/erc/erc-nicks-tests.el b/test/lisp/erc/erc-nicks-tests.el
index 08080d249d5..c865a902a0e 100644
--- a/test/lisp/erc/erc-nicks-tests.el
+++ b/test/lisp/erc/erc-nicks-tests.el
@@ -30,8 +30,11 @@
 
 ;;; Code:
 
-(require 'ert-x)
 (require 'erc-nicks)
+(require 'ert-x)
+(eval-and-compile
+  (let ((load-path (cons (ert-resource-directory) load-path)))
+    (require 'erc-tests-common)))
 
 ;; This function replicates the behavior of older "invert" strategy
 ;; implementations from EmacsWiki, etc.  The values for the lower and
@@ -568,4 +571,268 @@ erc-nicks--create-coerced-pool
 
     (should (equal erc-nicks--colors-rejects '(t)))))
 
+(declare-function erc-track-modified-channels "erc-track" ())
+
+(defun erc-nicks-tests--track-faces (test)
+  (require 'erc-track)
+  (defvar erc-modified-channels-alist)
+  (defvar erc-track--normal-faces)
+
+  (erc-tests-common-make-server-buf)
+  (erc-nicks-mode +1)
+
+  (let ((erc-modules (cons 'nicks erc-modules))
+        ;; Pretend these faces were added in response-handling during
+        ;; insertion modification by buttonizing hooks.  See
+        ;; `erc-nicks--highlight-button'.
+        (add-face (lambda (face)
+                    (erc-nicks--remember-face-for-track ; speaker
+                     (list face 'erc-nick-default-face))
+                    (erc-nicks--remember-face-for-track ; mention
+                     (list face 'erc-default-face))))
+        ;;
+        bob-face alice-face assert-result)
+
+    (with-current-buffer (erc--open-target "#chan")
+      (should erc-nicks-mode)
+      (should (setq bob-face (erc-nicks--get-face "bob" "bob@foonet")))
+      (should (setq alice-face (erc-nicks--get-face "alice" "alice@foonet")))
+
+      (erc-tests-common-track-modified-channels-sans-setup
+
+       (lambda (set-faces)
+
+         (setq assert-result ; fixture binds `erc-modified-channels-alist'
+               (lambda (result)
+                 (should (equal (alist-get (current-buffer)
+                                           erc-modified-channels-alist)
+                                result))))
+
+         (funcall test set-faces assert-result add-face
+                  bob-face alice-face)))))
+
+  (erc-tests-common-kill-buffers))
+
+(ert-deftest erc-nicks-track-faces/prioritize ()
+  (should (eq erc-nicks-track-faces 'prioritize))
+  (erc-nicks-tests--track-faces
+   (lambda (set-faces assert-result add-face bob-face alice-face)
+
+     (defvar erc-track--alt-normals-function)
+     (should erc-track--alt-normals-function)
+
+     (funcall add-face bob-face)
+     (funcall add-face alice-face)
+
+     ;; Simulate a JOIN.
+     (funcall set-faces '(erc-notice-face))
+     (erc-track-modified-channels)
+     (funcall assert-result '(1 . erc-notice-face))
+
+     ;; Someone speaks, and the mode-line changes to a `nicks' owned
+     ;; composite face for the speaker.
+     (funcall set-faces `(erc-timestamp-face
+                          (,bob-face erc-nick-default-face)
+                          erc-default-face))
+     (erc-track-modified-channels)
+     (funcall assert-result `(2 ,bob-face erc-nick-default-face))
+
+     ;; That same someone speaks, and the mode-line indicator changes to
+     ;; another "normal" face in the message body.
+     (funcall set-faces `(erc-timestamp-face
+                          (,bob-face erc-nick-default-face)
+                          erc-default-face))
+     (erc-track-modified-channels)
+     (funcall assert-result '(3 . erc-default-face))
+
+     ;; And yet again, which results in the indicator going back to one.
+     (funcall set-faces `(erc-timestamp-face
+                          (,bob-face erc-nick-default-face)
+                          erc-default-face))
+     (erc-track-modified-channels)
+     (funcall assert-result `(4 ,bob-face erc-nick-default-face))
+
+     ;; Now the same person mentions another server user, resulting in a
+     ;; change to *that* `nicks' owned face because it appears later in
+     ;; the message content (timestamp is last).
+     (funcall set-faces `(erc-timestamp-face
+                          (,alice-face erc-default-face)
+                          (,bob-face erc-nick-default-face)
+                          erc-default-face))
+     (erc-track-modified-channels)
+     (funcall assert-result `(5 ,alice-face erc-default-face))
+
+     ;; The mentioned user replies, mentioning the mentioner.  But
+     ;; instead of the normal "normals" processing preferring the ranked
+     ;; `erc-default-face', the `erc-nicks-track-faces' logic kicks in
+     ;; via `erc-track--alt-normals-function' and provides a `nicks'
+     ;; owned replacement.
+     (funcall set-faces `(erc-timestamp-face
+                          (,bob-face erc-default-face)
+                          (,alice-face erc-nick-default-face)
+                          erc-default-face))
+     (erc-track-modified-channels)
+     (funcall assert-result `(6 ,bob-face erc-default-face))
+
+     ;; Finally, another notice arrives.
+     (funcall set-faces '(erc-notice-face))
+     (erc-track-modified-channels)
+     (funcall assert-result '(7 . erc-notice-face)))))
+
+(ert-deftest erc-nicks-track-faces/defer ()
+  (should (eq erc-nicks-track-faces 'prioritize))
+  (let ((erc-nicks-track-faces 'defer))
+    (erc-nicks-tests--track-faces
+     (lambda (set-faces assert-result add-face bob-face alice-face)
+
+       (funcall add-face bob-face)
+       (funcall add-face alice-face)
+
+       ;; Simulate a JOIN.
+       (funcall set-faces '(erc-notice-face))
+       (erc-track-modified-channels)
+       (funcall assert-result '(1 . erc-notice-face))
+
+       ;; Someone speaks, and the mode-line indicator changes to the
+       ;; highest ranked face in the message.  (All `nicks' owned faces
+       ;; are unranked).
+       (funcall set-faces `(erc-timestamp-face
+                            (,bob-face erc-nick-default-face)
+                            erc-default-face))
+       (erc-track-modified-channels)
+       (funcall assert-result `(2 . erc-default-face))
+
+       ;; That same someone speaks, and the mode-line indicator changes
+       ;; to a `nicks' owned face.  It first reaches for the highest
+       ;; ranked face in the message but then applies the "normals"
+       ;; rules, resulting in a promoted alternate.
+       (funcall set-faces `(erc-timestamp-face
+                            (,bob-face erc-nick-default-face)
+                            erc-default-face))
+       (erc-track-modified-channels)
+       (funcall assert-result `(3 ,bob-face erc-nick-default-face))
+
+       ;; And yet again, which results in the indicator going back to one.
+       (funcall set-faces `(erc-timestamp-face
+                            (,bob-face erc-nick-default-face)
+                            erc-default-face))
+       (erc-track-modified-channels)
+       (funcall assert-result '(4 . erc-default-face))
+
+       ;; The same person mentions another server user, resulting in a
+       ;; change to that `nicks' owned face because the logic from
+       ;; 3. again applies.
+       (funcall set-faces `(erc-timestamp-face
+                            (,alice-face erc-default-face)
+                            (,bob-face erc-nick-default-face)
+                            erc-default-face))
+       (erc-track-modified-channels)
+       (funcall assert-result `(5 ,alice-face erc-default-face))
+
+       ;; The mentioned user replies, mentioning the mentioner.
+       ;; However, the `nicks' module does not intercede in the decision
+       ;; making to overrule the ranked nominee.
+       (funcall set-faces `(erc-timestamp-face
+                            (,bob-face erc-default-face)
+                            (,alice-face erc-nick-default-face)
+                            erc-default-face))
+       (erc-track-modified-channels)
+       (funcall assert-result '(6 . erc-default-face))
+
+       ;; Finally, another notice arrives.
+       (funcall set-faces '(erc-notice-face))
+       (erc-track-modified-channels)
+       (funcall assert-result '(7 . erc-notice-face))))))
+
+(ert-deftest erc-nicks-track-faces/nil ()
+  (should (eq erc-nicks-track-faces 'prioritize))
+  (let (erc-nicks-track-faces)
+    (erc-nicks-tests--track-faces
+     (lambda (set-faces assert-result _ bob-face alice-face)
+
+       (defvar erc-track--face-reject-function)
+       (should erc-track--face-reject-function)
+
+       ;; Simulate a JOIN.
+       (funcall set-faces '(erc-notice-face))
+       (erc-track-modified-channels)
+       (funcall assert-result '(1 . erc-notice-face))
+
+       ;; Someone speaks, and the mode-line indicator changes to the
+       ;; only ranked face in the message.
+       (funcall set-faces `(erc-timestamp-face
+                            (,bob-face erc-nick-default-face)
+                            erc-default-face))
+       (erc-track-modified-channels)
+       (funcall assert-result `(2 . erc-default-face))
+
+       ;; That same someone speaks, and since no other "normals" exist
+       ;; in the message, the indicator is not updated.
+       (funcall set-faces `(erc-timestamp-face
+                            (,bob-face erc-nick-default-face)
+                            erc-default-face))
+       (erc-track-modified-channels)
+       (funcall assert-result '(3 . erc-default-face))
+
+       ;; Now the same person mentions another server user, but the same
+       ;; logic applies, and the indicator is not updated.
+       (funcall set-faces `(erc-timestamp-face
+                            (,alice-face erc-default-face)
+                            (,bob-face erc-nick-default-face)
+                            erc-default-face))
+       (erc-track-modified-channels)
+       (funcall assert-result `(4 . erc-default-face))
+
+       ;; Finally, another notice arrives.
+       (funcall set-faces '(erc-notice-face))
+       (erc-track-modified-channels)
+       (funcall assert-result '(5 . erc-notice-face))))))
+
+(ert-deftest erc-nicks-track-faces/t ()
+  (should (eq erc-nicks-track-faces 'prioritize))
+  (let ((erc-nicks-track-faces t))
+    (erc-nicks-tests--track-faces
+     (lambda (set-faces assert-result add-face bob-face alice-face)
+
+       (defvar erc-track--alt-normals-function)
+       (should erc-track--alt-normals-function)
+
+       (funcall add-face bob-face)
+       (funcall add-face alice-face)
+
+       ;; Simulate a JOIN.
+       (funcall set-faces '(erc-notice-face))
+       (erc-track-modified-channels)
+       (funcall assert-result '(1 . erc-notice-face))
+
+       ;; Someone speaks, and the mode-line indicator changes to that
+       ;; someone's `nicks'-owned face.
+       (funcall set-faces `(erc-timestamp-face
+                            (,bob-face erc-nick-default-face)
+                            erc-default-face))
+       (erc-track-modified-channels)
+       (funcall assert-result `(2 ,bob-face erc-nick-default-face))
+
+       ;; That same someone speaks, and though one other "normal" exists
+       ;; in the message, `erc-default-face', no update occurs.
+       (funcall set-faces `(erc-timestamp-face
+                            (,bob-face erc-nick-default-face)
+                            erc-default-face))
+       (erc-track-modified-channels)
+       (funcall assert-result `(3 ,bob-face erc-nick-default-face))
+
+       ;; Another server user speaks, mentioning the previous speaker,
+       ;; and the indicator is updated to reflect the new speaker.
+       (funcall set-faces `(erc-timestamp-face
+                            (,bob-face erc-default-face) ; bob:
+                            (,alice-face erc-nick-default-face) ; <alice>
+                            erc-default-face))
+       (erc-track-modified-channels)
+       (funcall assert-result `(4 ,alice-face erc-nick-default-face))
+
+       ;; Finally, another notice arrives.
+       (funcall set-faces '(erc-notice-face))
+       (erc-track-modified-channels)
+       (funcall assert-result '(5 . erc-notice-face))))))
+
 ;;; erc-nicks-tests.el ends here
diff --git a/test/lisp/erc/erc-track-tests.el b/test/lisp/erc/erc-track-tests.el
index 8149138a971..c830c8b2016 100644
--- a/test/lisp/erc/erc-track-tests.el
+++ b/test/lisp/erc/erc-track-tests.el
@@ -227,6 +227,13 @@ erc-track-select-mode-line-face
 (defun erc-track-tests--select-mode-line-face (ranked normals cases)
   (setq normals (map-into (mapcar (lambda (f) (cons f t)) normals)
                           '(hash-table :test equal)))
+
+  (setq ranked (cons (map-into (mapcar (let ((i 0))
+                                         (lambda (f) (cons f (cl-incf i))))
+                                       ranked)
+                               '(hash-table :test equal))
+                     ranked))
+
   (pcase-dolist (`(,want ,cur-face ,new-faces) cases)
 
     (ert-info ((format "Observed: {cur: %S, new: %S, want: %S}"
@@ -235,8 +242,8 @@ erc-track-tests--select-mode-line-face
                              (mapcar (lambda (f) (cons f t)) new-faces)
                              '(hash-table :test equal))
                             (reverse new-faces)))
-      (should (equal want (funcall #'erc-track--select-mode-line-face
-                                   cur-face new-faces ranked normals))))))
+      (should (equal want (erc-track--select-mode-line-face
+                           cur-face new-faces ranked normals))))))
 
 ;; The main difference between these variants is that with the above,
 ;; when given alternating lines like
@@ -410,4 +417,255 @@ erc-track--collect-faces-in
     (when noninteractive
       (kill-buffer))))
 
+(defun erc-track-tests--modified-channels/baseline (set-faces)
+  ;; Simulate a JOIN, PART, etc. that's displayed in `erc-notice-face'.
+  (funcall set-faces '(erc-notice-face))
+  (erc-track-modified-channels)
+  (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                 '(1 . erc-notice-face)))
+
+  ;; Someone speaks, and the mode-line face goes from ERC's generic
+  ;; "notice" face, `erc-notice-face', to the first face in the
+  ;; inserted message that outranks it, which happens to be the
+  ;; `button' module's composite face for buttonized speakers:
+  ;; (erc-button-nick-default-face erc-nick-default-face).  It
+  ;; outranks both the previous occupant, `erc-notice-face', and its
+  ;; one cohabitant in the message text, `erc-default-face', in
+  ;; `erc-track-faces-priority-list'.  Note that in the following
+  ;; list, `erc-default-face' appears first because it's used for the
+  ;; opening speaker bracket "<".  The timestamp appears last because
+  ;; it's a right-sided stamp appended to the message body.
+  (funcall set-faces '(erc-timestamp-face
+                       (erc-button-nick-default-face erc-nick-default-face)
+                       erc-default-face))
+  (erc-track-modified-channels)
+  (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                 '(2 erc-button-nick-default-face erc-nick-default-face)))
+
+  ;; The speaker speaks again immediately, and the segment changes to
+  ;; `erc-default-face', which appears later in the message, as
+  ;; normal body text.  This happens because both `erc-default-face'
+  ;; and (erc-button-nick-default-face erc-nick-default-face) appear
+  ;; in `erc-track-faces-normal-list', meaning the lower-ranked
+  ;; former can replace the higher-ranked latter in the mode-line for
+  ;; the purpose of indicating channel activity.
+  (funcall set-faces '(erc-timestamp-face
+                       (erc-button-nick-default-face erc-nick-default-face)
+                       erc-default-face))
+  (erc-track-modified-channels)
+  (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                 '(3 . erc-default-face)))
+
+  ;; Note: if (erc-button-nick-default-face erc-nick-default-face)
+  ;; were removed from `erc-track-faces-priority-list' but kept in
+  ;; `erc-track-faces-normal-list', then replaying the sequence would
+  ;; result in the previous two results being switched:
+  ;; `erc-default-face' would replace `erc-notice-face' before being
+  ;; replaced by the buttonized composite.
+
+  ;; The speaker speaks yet again, and the segment goes back to the
+  ;; higher ranking face.
+  (funcall set-faces '(erc-timestamp-face
+                       (erc-button-nick-default-face erc-nick-default-face)
+                       erc-default-face))
+  (erc-track-modified-channels)
+  (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                 '(4 erc-button-nick-default-face erc-nick-default-face)))
+
+  ;; Finally, another notice arrives.  Although lower ranked, it also
+  ;; appears in `erc-track-faces-normal-list' and so is eligible to
+  ;; replace the incumbent.
+  (funcall set-faces '(erc-notice-face))
+  (erc-track-modified-channels)
+  (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                 '(5 . erc-notice-face))))
+
+(ert-deftest erc-track-modified-channels/baseline ()
+  (erc-tests-common-track-modified-channels
+   #'erc-track-tests--modified-channels/baseline))
+
+(ert-deftest erc-track-modified-channels/baseline/mention ()
+  (erc-tests-common-track-modified-channels
+   (lambda (set-faces)
+     ;; Note: these messages don't have timestamps.
+
+     ;; Simulate a JOIN, PART, etc. that's displayed in `erc-notice-face'.
+     (funcall set-faces '(erc-notice-face))
+     (erc-track-modified-channels)
+     (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                    '(1 . erc-notice-face)))
+
+     ;; Someone speaks, mentioning someone else, and the mode-line
+     ;; changes to (erc-button-nick-default-face erc-nick-default-face)
+     ;; rather than (erc-button-nick-default-face erc-default-face)
+     ;; based on their rankings in `erc-track-faces-priority-list'.
+     (funcall set-faces '((erc-button-nick-default-face erc-default-face)
+                          (erc-button-nick-default-face erc-nick-default-face)
+                          erc-default-face))
+     (erc-track-modified-channels)
+     (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                    '(2 erc-button-nick-default-face erc-nick-default-face)))
+
+     ;; Someone else speaks, again with a mention and additional body text.
+     (funcall set-faces '((erc-button-nick-default-face erc-default-face)
+                          (erc-button-nick-default-face erc-nick-default-face)
+                          erc-default-face))
+     (erc-track-modified-channels)
+     (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                    '(3 erc-button-nick-default-face erc-default-face)))
+
+     ;; And yet again, which results in the indicator going back to one.
+     (funcall set-faces '((erc-button-nick-default-face erc-default-face)
+                          (erc-button-nick-default-face erc-nick-default-face)
+                          erc-default-face))
+     (erc-track-modified-channels)
+     (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                    '(4 erc-button-nick-default-face erc-nick-default-face)))
+
+     ;; Finally, another notice arrives.
+     (funcall set-faces '(erc-notice-face))
+     (erc-track-modified-channels)
+     (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                    '(5 . erc-notice-face))))))
+
+;; The compat-oriented option `erc-track-ignore-normal-contenders-p'
+;; blinds track to `erc-track-faces-normal-list' for certain consecutive
+;; messages with an identical face makeup.
+(ert-deftest erc-track-modified-channels/baseline/ignore ()
+  (let ((erc-track-ignore-normal-contenders-p t))
+    (erc-tests-common-track-modified-channels
+     (lambda (set-faces)
+       ;; Simulate a JOIN, PART, etc. that's displayed in `erc-notice-face'.
+       (funcall set-faces '(erc-notice-face))
+       (erc-track-modified-channels)
+       (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                      '(1 . erc-notice-face)))
+
+       ;; Someone speaks, and the mode-line indicator's face changes to
+       ;; that of a buttonized speaker.
+       (funcall set-faces
+                '(erc-timestamp-face
+                  (erc-button-nick-default-face erc-nick-default-face)
+                  erc-default-face))
+       (erc-track-modified-channels)
+       (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                      '(2 erc-button-nick-default-face erc-nick-default-face)))
+
+       ;; The speaker speaks again immediately, and the segment doesn't
+       ;; change.
+       (funcall set-faces
+                '(erc-timestamp-face
+                  (erc-button-nick-default-face erc-nick-default-face)
+                  erc-default-face))
+       (erc-track-modified-channels)
+       (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                      '(3 erc-button-nick-default-face erc-nick-default-face)))
+
+       ;; Finally, another notice arrives.
+       (funcall set-faces '(erc-notice-face))
+       (erc-track-modified-channels)
+       (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                      '(4 . erc-notice-face)))))))
+
+;; Compat-oriented option `erc-track-ignore-normal-contenders-p'.
+(ert-deftest erc-track-modified-channels/baseline/mention/ignore ()
+  (let ((erc-track-ignore-normal-contenders-p t))
+    (erc-tests-common-track-modified-channels
+     (lambda (set-faces)
+
+       ;; Simulate a JOIN, PART, etc. that's displayed in `erc-notice-face'.
+       (funcall set-faces '(erc-notice-face))
+       (erc-track-modified-channels)
+       (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                      '(1 . erc-notice-face)))
+
+       ;; Someone speaks, and the mode-line indicator's face changes to
+       ;; that of a buttonized speaker.
+       (funcall set-faces
+                '((erc-button-nick-default-face erc-default-face)
+                  (erc-button-nick-default-face erc-nick-default-face)
+                  erc-default-face))
+       (erc-track-modified-channels)
+       (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                      '(2 erc-button-nick-default-face erc-nick-default-face)))
+
+       ;; Someone else speaks, again with a mention and additional body
+       ;; text, but the indicator stays the same.
+       (funcall set-faces
+                '((erc-button-nick-default-face erc-default-face)
+                  (erc-button-nick-default-face erc-nick-default-face)
+                  erc-default-face))
+       (erc-track-modified-channels)
+       (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                      '(3 erc-button-nick-default-face erc-nick-default-face)))
+
+       ;; Finally, another notice arrives.
+       (funcall set-faces '(erc-notice-face))
+       (erc-track-modified-channels)
+       (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                      '(4 . erc-notice-face)))))))
+
+;; Option `erc-track-priority-faces-only' does not affect the behavior
+;; of the baseline "normals" scenario because all faces appear in
+;; `erc-track-faces-priority-list'.
+(ert-deftest erc-track-modified-channels/priority-only-all/baseline ()
+  (let ((erc-track-priority-faces-only 'all))
+    (erc-tests-common-track-modified-channels
+     #'erc-track-tests--modified-channels/baseline)))
+
+;; This test simulates a common configuration that combines an
+;; `erc-track-faces-priority-list' removed of `erc-notice-face' with
+;; `erc-track-priority-faces-only' being `all'.  It also features in the
+;; sample configuration in ERC's manual.
+(ert-deftest erc-track-modified-channels/priority-only-all/sans-notice ()
+  (let ((erc-track-priority-faces-only 'all)
+        (erc-track-faces-priority-list
+         (remq 'erc-notice-face erc-track-faces-priority-list)))
+
+    (erc-tests-common-track-modified-channels
+     (lambda (set-faces)
+       ;; Note: these messages don't have timestamps.
+
+       ;; Simulate a message normally displayed in `erc-notice-face',
+       ;; which has been removed from `erc-track-faces-priority-list'.
+       (funcall set-faces '(erc-notice-face))
+       (erc-track-modified-channels)
+       (should-not (alist-get (current-buffer) erc-modified-channels-alist))
+
+       ;; Someone speaks, mentioning someone else, and the mode-line
+       ;; changes to the buttonized speaker face rather than the
+       ;; buttonized mention face, due to their respective ranks.
+       (funcall set-faces
+                '((erc-button-nick-default-face erc-default-face)
+                  (erc-button-nick-default-face erc-nick-default-face)
+                  erc-default-face))
+       (erc-track-modified-channels)
+       (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                      '(1 erc-button-nick-default-face erc-nick-default-face)))
+
+       ;; Someone else speaks, again with a mention and additional body text.
+       (funcall set-faces
+                '((erc-button-nick-default-face erc-default-face)
+                  (erc-button-nick-default-face erc-nick-default-face)
+                  erc-default-face))
+       (erc-track-modified-channels)
+       (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                      '(2 erc-button-nick-default-face erc-default-face)))
+
+       ;; And yet again, which results in the indicator going back to one.
+       (funcall set-faces
+                '((erc-button-nick-default-face erc-default-face)
+                  (erc-button-nick-default-face erc-nick-default-face)
+                  erc-default-face))
+       (erc-track-modified-channels)
+       (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                      '(3 erc-button-nick-default-face erc-nick-default-face)))
+
+       ;; Finally, another notice arrives, which is ignored.
+       (funcall set-faces '(erc-notice-face))
+       (erc-track-modified-channels)
+       (should (equal (alist-get (current-buffer) erc-modified-channels-alist)
+                      '(3 erc-button-nick-default-face
+                          erc-nick-default-face)))))))
+
 ;;; erc-track-tests.el ends here
diff --git a/test/lisp/erc/resources/erc-tests-common.el b/test/lisp/erc/resources/erc-tests-common.el
index 1cd54a1f715..91654467dae 100644
--- a/test/lisp/erc/resources/erc-tests-common.el
+++ b/test/lisp/erc/resources/erc-tests-common.el
@@ -330,4 +330,47 @@ erc-tests-common-create-subprocess
     (set-process-query-on-exit-flag proc t)
     proc))
 
+(declare-function erc-track--setup "erc-track" ())
+
+(defun erc-tests-common-track-modified-channels (test)
+  (erc-tests-common-prep-for-insertion)
+  (setq erc--target (erc--target-from-string "#chan"))
+  (erc-tests-common-track-modified-channels-sans-setup test))
+
+(defun erc-tests-common-track-modified-channels-sans-setup (test)
+  "Provide a fixture for testing `erc-track-modified-channels'.
+Call function TEST with another function that sets the mocked return
+value of `erc-track--collect-faces-in' to the given argument, a list of
+faces in the reverse order they appear in an inserted message."
+  (defvar erc-modified-channels-alist)
+  (defvar erc-modified-channels-object)
+  (defvar erc-track--attn-faces)
+  (defvar erc-track--normal-faces)
+  (defvar erc-track--priority-faces)
+  (defvar erc-track-faces-normal-list)
+  (defvar erc-track-faces-priority-list)
+  (defvar erc-track-mode)
+
+  (cl-letf* ((erc-track-mode t)
+             (erc-modified-channels-alist nil)
+             (erc-modified-channels-object erc-modified-channels-object)
+             (faces ())
+             ((symbol-function 'force-mode-line-update) #'ignore)
+             ((symbol-function 'erc-faces-in) (lambda (_) faces))
+             ((symbol-function 'erc-track--collect-faces-in)
+              (lambda ()
+                (cons (map-into (mapcar (lambda (f) (cons f t)) faces)
+                                '(hash-table :test equal))
+                      faces))))
+    (erc-track--setup)
+
+    ;; Faces from `erc-track--attn-faces' prepended.
+    (should (= (+ (length erc-track--attn-faces)
+                  (length erc-track-faces-priority-list))
+               (hash-table-count erc-track--priority-faces)))
+    (should (= (length erc-track-faces-normal-list)
+               (hash-table-count erc-track--normal-faces)))
+
+    (funcall test (lambda (arg) (setq faces arg)))))
+
 (provide 'erc-tests-common)
-- 
2.46.2


^ permalink raw reply related	[flat|nested] 9+ messages in thread

* bug#67767: 30.0.50; ERC 5.6: Add track integration to the nicks module
       [not found]   ` <87ldz4b77j.fsf@neverwas.me>
@ 2024-10-05  1:40     ` J.P.
  2024-10-15  3:02     ` J.P.
  1 sibling, 0 replies; 9+ messages in thread
From: J.P. @ 2024-10-05  1:40 UTC (permalink / raw)
  To: 67767; +Cc: emacs-erc

"J.P." <jp@neverwas.me> writes:

> +(defun erc-nicks--track-always (current contender contenders ranks normals)
> +  "Return a viable `nicks' face, possibly CURRENT, among CONTENDERS.
> +See `erc-track--select-mode-line-face' for parameter types."
> +  (when-let
> +      ((spkr (erc-nicks--assess-track-faces current contender ranks normals)))
> +    (catch 'contender
> +      (dolist (candidate (cdr (reverse contenders)))
                             ~~~~~~~~~~~~~~~~~~~~~~~

That should be

         (dolist (candidate (reverse (cdr contenders)))

Also, `spkr' is unused.

> +        (when (erc-nicks--ours-p candidate)
> +          (cl-assert (gethash candidate normals))
>            (throw 'contender candidate))))))
>  
>  (defun erc-nicks--setup-track-integration ()





^ permalink raw reply	[flat|nested] 9+ messages in thread

* bug#67767: 30.0.50; ERC 5.6: Add track integration to the nicks module
       [not found]   ` <87ldz4b77j.fsf@neverwas.me>
  2024-10-05  1:40     ` J.P.
@ 2024-10-15  3:02     ` J.P.
  1 sibling, 0 replies; 9+ messages in thread
From: J.P. @ 2024-10-15  3:02 UTC (permalink / raw)
  To: 67767; +Cc: emacs-erc

"J.P." <jp@neverwas.me> writes:

> Attached is a v2 introducing a `t' choice for `erc-nicks-track-faces'.
> It suppresses the "alternating" effect associated with the option
> `erc-track-faces-normal-list'.

This was added recently as

  9906e34f973 Crystallize erc-nicks-track-faces behavior

The bug is already closed.





^ permalink raw reply	[flat|nested] 9+ messages in thread

end of thread, other threads:[~2024-10-15  3:02 UTC | newest]

Thread overview: 9+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2023-12-11 15:28 bug#67767: 30.0.50; ERC 5.6: Add track integration to the nicks module J.P.
2023-12-12  2:18 ` J.P.
2023-12-12 14:49 ` J.P.
2023-12-13 14:06 ` J.P.
     [not found] ` <8734w6yz76.fsf@neverwas.me>
2023-12-18 14:51   ` J.P.
2024-09-30  0:34 ` J.P.
     [not found] ` <87ed52q8rd.fsf@neverwas.me>
2024-10-04  8:30   ` J.P.
     [not found]   ` <87ldz4b77j.fsf@neverwas.me>
2024-10-05  1:40     ` J.P.
2024-10-15  3:02     ` J.P.

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