From dabd42adc78ef3c3e8f40f913325941246993628 Mon Sep 17 00:00:00 2001
From: Spencer Baugh <sbaugh@janestreet.com>
Date: Wed, 18 Sep 2024 08:52:54 -0400
Subject: [PATCH] Preserve suffix in emacs22 style

---
 lisp/minibuffer.el | 14 ++++++++++++--
 lisp/simple.el     | 11 +++++++----
 2 files changed, 19 insertions(+), 6 deletions(-)

diff --git a/lisp/minibuffer.el b/lisp/minibuffer.el
index 804afe9cb43..a28041751aa 100644
--- a/lisp/minibuffer.el
+++ b/lisp/minibuffer.el
@@ -3771,10 +3771,20 @@ completion-emacs22-try-completion
           (setq suffix (substring suffix 1)))
       (cons (concat completion suffix) (length completion))))))
 
+(defface completions-ignored
+  '((t (:inherit shadow)))
+  "Face for text which was ignored by the completion style.")
+
 (defun completion-emacs22-all-completions (string table pred point)
-  (let ((beforepoint (substring string 0 point)))
+  (let ((beforepoint (substring string 0 point))
+        (suffix (propertize (substring string point) 'face 'completions-ignored)))
     (completion-hilit-commonality
-     (all-completions beforepoint table pred)
+     (mapcar
+      (lambda (elem)
+        (let ((s (concat elem suffix)))
+          (put-text-property 0 1 'completion-position-after-insert (length elem) s)
+          s))
+      (all-completions beforepoint table pred))
      point
      (car (completion-boundaries beforepoint table pred "")))))
 
diff --git a/lisp/simple.el b/lisp/simple.el
index e35cfe0479b..881eb51e57a 100644
--- a/lisp/simple.el
+++ b/lisp/simple.el
@@ -10371,10 +10371,13 @@ choose-completion-string
         ;; comes from buffer-substring-no-properties.
         ;;(remove-text-properties 0 (length choice) '(mouse-face nil) choice)
 	;; Insert the completion into the buffer where it was requested.
-        (funcall (or insert-function completion-list-insert-choice-function)
-                 (or (car base-position) (point))
-                 (or (cadr base-position) (point))
-                 choice)
+        (let ((beg (or (car base-position) (point)))
+              (end (or (cadr base-position) (point))))
+          (funcall (or insert-function completion-list-insert-choice-function)
+                   beg end choice)
+          (unless (string-empty-p choice)
+            (when-let ((pos (get-text-property 0 'completion-position-after-insert choice)))
+              (goto-char (+ pos beg)))))
         ;; Update point in the window that BUFFER is showing in.
 	(let ((window (get-buffer-window buffer t)))
 	  (set-window-point window (point)))
-- 
2.39.3