Subject: bug#48535: 28.0.50; ff-find-other-file no longer sets current-buffer?

From: Stephen Leake <[email-masked]>
Date: Sun, 23 May 2021 14:56:57 -0700

Stephen Leake <[email-masked]> writes:

> Stephen Leake <[email-masked]> writes:
>
>> Stephen Leake <[email-masked]> writes:
>>
>>>> I've confirmed that disabling lexical-binding fixes the problem.
>>>
>>> On the other hand, re-enabling lexical-binding, and byte-compiling just
>>> that file (which 'make' does), the problem does not come back. Sigh.
>>
>> I was confused; I was working in a 'good' commit, not the first 'bad'
>> commit.
>>
>> Disabling lexical-binding in find-file.el does not fix the problem in
>> the 'bad' commit.
>
> The attached patch fixes the problem, in master HEAD (c9655fcb47).

actually attach the patch
-- 
-- Stephe
diff --git a/lisp/find-file.el b/lisp/find-file.el
index 6c3c0f123b..4fd4f4e06b 100644
--- a/lisp/find-file.el
+++ b/lisp/find-file.el
@@ -305,6 +305,10 @@ ff-find-other-file
 If optional IN-OTHER-WINDOW is non-nil, find the file in the other window.
 If optional IGNORE-INCLUDE is non-nil, ignore being on `#include' lines.
 
+If optional EVENT is non-nil (default `last-nonmenu-event', move
+point to the end position of that event before calling the
+various ff-* hooks.
+
 Variables of interest include:
 
  - `ff-case-fold-search'
@@ -351,10 +355,16 @@ ff-find-other-file
  - `ff-file-created-hook'
    List of functions to be called if the other file has been created."
   (interactive (list current-prefix-arg nil last-nonmenu-event))
-  (save-excursion
+  ;; We want to preserve point in the current buffer. But the point of
+  ;; ff-find-the-other-file is to make the the other file buffer
+  ;; current, so we can't use save-excursion here (see bug 48535).
+  (let ((start-buffer (current-buffer))
+        (start-point (point)))
     (posn-set-point (event-end event))
     (let ((ff-ignore-include ignore-include))
-      (ff-find-the-other-file in-other-window))))
+      (ff-find-the-other-file in-other-window))
+    (with-current-buffer start-buffer
+      (goto-char start-point))))
 
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