Re: Commit for emacs-25, fixing undo with revert-buffer

[phillip.lord@russet.org.uk (Phillip Lord)]

Eli Zaretskii <eliz@gnu.org> writes:
>> Stefan, just pinging. Would like to get this bug cleared anyway (you've
>> seen this patch already, although I think I have cleaned it up a bit).
>
> I think you have the bug number wrong, and Stefan did respond to your
> patch wrt bug#23871:
>
>   http://debbugs.gnu.org/cgi/bugreport.cgi?bug=23871#98


Sorry, different one. Bug# 23785 and this patch.

Phil




>From d425b7875b162cabf65661e42b62b5e54344ffe6 Mon Sep 17 00:00:00 2001
From: Phillip Lord <phillip.lord@russet.org.uk>
Date: Tue, 28 Jun 2016 08:02:51 +0100
Subject: [PATCH] Fix missing undo-boundary on revert-buffer.

* src/fileio.c (insert-file-contents): Call undo-auto--undoable-change

Addresses Bug#23785.

Do not merge to master as c98bc98 also addresses the same bug.
---
 lisp/simple.el | 10 +++++++++-
 src/fileio.c   |  5 +++++
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/lisp/simple.el b/lisp/simple.el
index b66827d..43ad43c 100644
--- a/lisp/simple.el
+++ b/lisp/simple.el
@@ -2940,9 +2940,17 @@ undo-auto-amalgamate
                         (cdr buffer-undo-list))))))
         (setq undo-auto--last-boundary-cause 0)))))

+;; This function is called also from one place in fileio.c. We call
+;; this function, rather than undoable-change because it reduces the
+;; number of lisp functions we have to use fboundp for to avoid
+;; bootstrap issues.
+(defun undo-auto--undoable-change-no-timer ()
+  "Record `current-buffer' as changed."
+  (add-to-list 'undo-auto--undoably-changed-buffers (current-buffer)))
+
 (defun undo-auto--undoable-change ()
   "Called after every undoable buffer change."
-  (add-to-list 'undo-auto--undoably-changed-buffers (current-buffer))
+  (undo-auto--undoable-change-no-timer)
   (undo-auto--boundary-ensure-timer))
 ;; End auto-boundary section

diff --git a/src/fileio.c b/src/fileio.c
index b11f923..3005ca3 100644
--- a/src/fileio.c
+++ b/src/fileio.c
@@ -3436,6 +3436,9 @@ by calling `format-decode', which see.  */)
   if (!NILP (BVAR (current_buffer, read_only)))
     Fbarf_if_buffer_read_only (Qnil);

+  if (!NILP (Ffboundp (Qundo_auto__undoable_change_no_timer)))
+    call0 (Qundo_auto__undoable_change_no_timer);
+
   val = Qnil;
   p = Qnil;
   orig_filename = Qnil;
@@ -5797,6 +5800,8 @@ syms_of_fileio (void)
      which gives a list of operations it handles.  */
   DEFSYM (Qoperations, "operations");

+  DEFSYM (Qundo_auto__undoable_change_no_timer,
"undo-auto--undoable-change-no-timer");
+
   DEFSYM (Qexpand_file_name, "expand-file-name");
   DEFSYM (Qsubstitute_in_file_name, "substitute-in-file-name");
   DEFSYM (Qdirectory_file_name, "directory-file-name");
-- 
2.9.0