Re: Unbalanced change hooks (part 1)

[Richard Copley]

On 2 August 2016 at 03:34, Eli Zaretskii <address@hidden> wrote:
>> From: Richard Copley <address@hidden>
>> Date: Mon, 1 Aug 2016 21:13:01 +0100
>> Cc: Óscar Fuentes <address@hidden>,
>>       Emacs Development <address@hidden>
>>
>> > diff --git a/src/fileio.c b/src/fileio.c
>> > index b1f9d3c..0431cbc 100644
>> > --- a/src/fileio.c
>> > +++ b/src/fileio.c
>> > @@ -3440,6 +3440,7 @@ by calling `format-decode', which see.  */)
>> >    /* SAME_AT_END_CHARPOS counts characters, because
>> >       restore_window_points needs the old character count.  */
>> >    ptrdiff_t same_at_end_charpos = ZV;
>> > +  bool run_change_hooks;
>> >
>> >    if (current_buffer->base_buffer && ! NILP (visit))
>> >      error ("Cannot do file visiting in an indirect buffer");
>> > @@ -4077,7 +4078,9 @@ by calling `format-decode', which see.  */)
>> >      /* For a special file, all we can do is guess.  */
>> >      total = READ_BUF_SIZE;
>> >
>> > -  if (NILP (visit) && total > 0)
>> > +  run_change_hooks = ((NILP (visit) || !NILP (replace))
>> > +                      && total > 0);
>> > +  if (run_change_hooks)
>> >      {
>> >        if (!NILP (BVAR (current_buffer, file_truename))
>> >           /* Make binding buffer-file-name to nil effective.  */
>> > @@ -4313,8 +4316,7 @@ by calling `format-decode', which see.  */)
>> >    /* Call after-change hooks for the inserted text, aside from the case
>> >       of normal visiting (not with REPLACE), which is done in a new buffer
>> >       "before" the buffer is changed.  */
>> > -  if (inserted > 0 && total > 0
>> > -      && (NILP (visit) || !NILP (replace)))
>> > +  if (run_change_hooks)
>> >      {
>> >        signal_after_change (PT, 0, inserted);
>> >        update_compositions (PT, PT, CHECK_BORDER);
>> >
>> >
>> > Unfortunately, this amendment, by itself, doesn't fix #240[79]4, since
>> > there are other causes for the change hooks being improperly invoked.
>> >
>> > --
>> > Alan Mackenzie (Nuremberg, Germany).
>>
>> LGTM. It's hard to imagine anyone relying on the before-change hooks
>> _not_ being run, so it should be safe, at least, to make this change.
>
> That code is almost never run when REPLACE is non-nil, so doing that
> won't help.  See an earlier message that explained why.

Thanks Eli, I saw it. It's not the sort of discussion I care to get involved in.