Re: master 268e055e051: Limit VC-Dir status process output processing

Dmitry Gutov [11/Aug  6:55am +03] wrote:
> Hi Sean,
>
> Do you think we could change this improvement in a way that doesn't make
> the 'dir-status-files' backend actions coupled to VC-Dir?
>
> Some sort of setup that VC-Dir would do to its process buffer could lead
> to a more subtle approach.
>
> On 26/06/2026 16:53, Sean Whitton wrote:
>>       (let ((files (vc-git-dir-status-state->files git-state))
>> -          (allowed-exit 1))
>> +          (allowed-exit 1)
>> +          (limit vc-dir-process-output-limit))
>>         (erase-buffer)
>>         (pcase (vc-git-dir-status-state->stage git-state)
>>           ('update-index
>> @@ -756,7 +760,10 @@ or an empty string if none."
>>           ('diff-index
>>            (git-cmd files "diff-index" "--relative" "-z" "-M" "HEAD" "--")))
>>         (vc-run-delayed-success allowed-exit
>> -        (vc-git-after-dir-status-stage git-state)))))
>> +        (let ((vc-dir-process-output-limit limit))
>> +          (vc-dir-maybe-narrow-and-show-more-button
>> +           "(reported states may be incorrect)")
>> +          (vc-git-after-dir-status-stage git-state))))))
>
> The way it's implemented here any third-party caller of dir-status-files
> (diff-hl-dired might be the main one) now has to learn of the unrelated
> variable from vc-dir.el.
>
> Originally: https://github.com/dgutov/diff-hl/pull/294

Sorry about that.  How about this:

diff --git a/lisp/vc/vc-dir.el b/lisp/vc/vc-dir.el
index d75dce77493..d0711da91c8 100644
--- a/lisp/vc/vc-dir.el
+++ b/lisp/vc/vc-dir.el
@@ -1801,7 +1801,10 @@ vc-dir-maybe-narrow-and-show-more-button
 TEXT is passed on to `vc-dir-show-more-button'.
 Called by VC backend `dir-status-files' implementations."
   (when (and (natnump vc-dir-process-output-limit)
-             (> (buffer-size) vc-dir-process-output-limit))
+             (> (buffer-size) vc-dir-process-output-limit)
+             vc-parent-buffer
+             (with-current-buffer vc-parent-buffer
+               (derived-mode-p 'vc-dir-mode)))
     (narrow-to-region (point-min)
                       (save-excursion
                         (goto-char (+ (point-min)

-- 
Sean Whitton