patch: customize window resize behavior of *vc-diff* window

[Alan Salewski]

Hi,

I've attached a very simple patch for vc.el, made against the version
distributed as part of emacs 21.2. The Id tag at the top of the vc.el
file is:

    ;; $Id: vc.el,v 1.311.4.5 2002/03/05 13:41:05 spiegel Exp $

The patch creates a variable that is customizable by the user for
controlling the resizing behavior of the window that contains the
*vc-diff* buffer.


Motivation:

I work with multiple windows visible in a single emacs frame; some of
the windows are marked as 'dedicated' using `set-window-dedicated-p',
and are sized to be visible, but mostly out of the way:

    +---------------------------------------------------------+
    |                             |                           |
    |                             |                           |
    |                             |                           |
    |                             |                           |
    |                             |                           |
    |                             |                           |
    |                             |                           |
    |                             |                           |
    |          *vc-diff*          |    some source file       |
    |             or              |                           |
    |       some source file      |                           |
    |                             |                           |
    |                             |                           |
    |                             |                           |
    |                             |                           |
    |                             |                           |
    |                             |                           |
    |                             |                           |
    |                             |                           |
    |                             |                           |
    +-----------------------------+                           |
    |  *Completions* (dedicated)  |                           |
    |                             |                           |
    +-----------------------------+---------------------------+
    |                                                         |
    |                    *shell* (dedicated)                  |
    |                                                         |
    +---------------------------------------------------------+

With the above configuration, I do not want the size of the windows to
change because I want as much viewing area as possible for the source
windows. However, with the existing behavior, running `vc-diff' on the
source file on the top right may cause the *vc-diff* buffer to shrink
(sometimes quite a bit). This means that when I switch buffers from
*vc-diff* to some other source file in the window on the top left, I
need to resize the window to make it larger.

The attached patch simply allows the user to turn off this resizing, but
preserves the original behavior by default.

Please consider including this patch as part of the main vc.el
distribution.

Thanks,
-Al

-- 
Alan D. Salewski, Programmer
Charles Jones, LLC
e-mail: alans@charlesjones.com
voice: (609) 538-1000 x5512

vc.el.patch
Description: Text document