bug#11810: 24.1.50; `vc-diff' shrinks pre-existing window

[martin rudalics]

> I tried it with just my patch applied, and it didn't work, because in
> this case the stored height value was of already resized window:
> `display-buffer-record-window' is called from `window--display-buffer',
> and `display-buffer-use-some-window' calls `window--even-window-heights'
> before `window--display-buffer'.

I think we could do

    (when window
      (prog1
          (window--display-buffer buffer window 'reuse)
      (window--even-window-heights window)))

in `display-buffer-use-some-window'.

> Maybe that's fine, I'll just set the variable to nil.

OK

> Until then, the issue is somewhat alleviated by the fact that you can
> press 'z' or 'C-x k' instead of 'q', and both of these won't trigger
> height restoration.

I'm more concerned with the fact that an application might reuse the
shrunk window via `display-buffer'.

> If someone wants `shrink-window-if-...' to have no effect only in
> `vc-diff', well, that's a different goal.

But that's probably what some people want.

>> Let's close this thread as follows: Remove the `temp-buffer-resize-mode'
>> check in `quit-window' and add an integerp check for the third element.
>
> Agreed.

Can you install it?  Else please post the patch and a ChangeLog entry.

>> (1) have `vc-diff' use something similar to `with-output-to-temp-buffer'
>>      so that `temp-buffer-resize-mode' is honored,
>>
>> (2) resize the window only if `temp-buffer-resize-mode' is enabled, or
>
> Both 1 and 2 would be fine, I think, although 1 would require some extra
> work to make it work asynchronously. IIUC, `with-output-to-temp-buffer'
> waits until the called process completes, and `vc-diff' supports both
> synchronous and asynchronous execution.

We need a susbstitute for `with-output-to-temp-buffer' for
asynchronously filled buffers.

martin