bug#17809: 24.4.50; Completions display

[martin rudalics]

> Maybe it would be a good thing to add a new action parameter to
> `display-buffer' that would be like the existing `quit-function'
> in `with-current-buffer-window', and will call its body between
> displaying the buffer and applying final actions alists like
> (window-height . fit-window-to-buffer)

`display-buffer' has no body and hardly ever will get one.

> `dired-mark-pop-up' already uses `with-current-buffer-window' that is
> like `with-temp-buffer-window', but still has the same problem
> as the screenshot below demonstrates: it inserts the contents
> to the buffer before displaying it, so it has no way to get the
> final window dimensions while inserting the contents, and leaves
> empty columns.
>
> It's possible in `dired-mark-pop-up' to move formatting
> (i.e. the call to `dired-format-columns-of-files')
> from the BODY arg of `with-current-buffer-window'
> to its QUIT-FUNCTION arg, and it will fill the empty columns,
> because the formatting will happen after displaying the buffer.
>
> But then (window-height . fit-window-to-buffer) will be called
> on the empty buffer, that will always produce a small window
> with 3-lines height.

Then don't do that.  If you want to do both - formatting and fitting -
have QUIT-FUNCTION do that.  So in BODY put the text into the buffer and
in QUIT-FUNCTION first format the text according to what the window size
gives and then try to fit the window to the formatted text.

martin