From 633c775fdce2d251a322a51b680e989314cf87a3 Mon Sep 17 00:00:00 2001
From: Po Lu <luangruo@yahoo.com>
Date: Wed, 24 Apr 2024 11:45:31 +0800
Subject: [PATCH] More effectually prevent defun list wrapping in C-x C-w

* lisp/vc/log-edit.el (log-edit-fill-entry): Match and replace
with NBSPs the opening defun list also.

* test/lisp/vc/log-edit-tests.el
(log-edit-fill-entry-no-defun-list-wrapping): New test.

(cherry picked from commit 145a77808ebd36fffb2e9c0376f821f09733d045)
---
 lisp/vc/log-edit.el            | 10 +++++++++-
 test/lisp/vc/log-edit-tests.el | 18 ++++++++++++++++++
 2 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/lisp/vc/log-edit.el b/lisp/vc/log-edit.el
index 1f766eea455..d61a108b195 100644
--- a/lisp/vc/log-edit.el
+++ b/lisp/vc/log-edit.el
@@ -698,7 +698,15 @@ according to `fill-column'."
                     (save-excursion
                       (goto-char beg)
                       (when (re-search-forward
-                             "^[[:blank:]]*(.*\\([[:space:]]\\).*):"
+                             ;; Also replace spaces within defun lists
+                             ;; prefixed by a file name so that
+                             ;; fill-region never attempts to break
+                             ;; them, even if multiple items combine
+                             ;; with symbols to exceed the fill column
+                             ;; by the expressly permitted margin of 1
+                             ;; character.
+                             (concat "^\\([[:blank:]]*\\|\\* .*[[:blank:]]"
+                                     "\\)(.*\\([[:space:]]\\).*):")
                              end t)
                         (replace-regexp-in-region "[[:space:]]" " "
                                                   (setq space-beg
diff --git a/test/lisp/vc/log-edit-tests.el b/test/lisp/vc/log-edit-tests.el
index 8373156587d..db60d21f137 100644
--- a/test/lisp/vc/log-edit-tests.el
+++ b/test/lisp/vc/log-edit-tests.el
@@ -344,4 +344,22 @@ next line instead.")
       (let ((fill-column 20)) (log-edit-fill-entry))
       (should (equal (buffer-string) wanted)))))
 
+(ert-deftest log-edit-fill-entry-no-defun-list-wrapping ()
+  ;; This test verifies that the opening defun list of an entry is never
+  ;; broken, even in the event its length in total exceeds the fill
+  ;; column.
+  (let (string wanted)
+    (setq string "
+* src/androidfns.c (Fxw_display_color_p):
+(Fx_display_grayscale_p): Report color and/or grayscale properly.
+"
+          wanted "
+* src/androidfns.c (Fxw_display_color_p, Fx_display_grayscale_p):
+Report color and/or grayscale properly.
+")
+    (with-temp-buffer
+      (insert string)
+      (let ((fill-column 64)) (log-edit-fill-entry))
+      (should (equal (buffer-string) wanted)))))
+
 ;;; log-edit-tests.el ends here
-- 
2.39.5