From 6c3758972c5acee309f71cd38b6a242b7e26a199 Mon Sep 17 00:00:00 2001
From: Magnus Henoch <magnus.henoch@gmail.com>
Date: Wed, 13 Jan 2010 09:01:58 -0800
Subject: [PATCH] * vc-p4.el (vc-p4-previous-revision): New function,
 shamelessly copied from vc-svn.

[git-p4: depot-paths = "//guest/Ben_Key/vc-p4/,//guest/jonathan_kamens/vc-p4/,//guest/magnus_henoch/vc-p4/": change = 7546]
---
 vc-p4.el | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/vc-p4.el b/vc-p4.el
index 17881b8..9d0b479 100644
--- a/vc-p4.el
+++ b/vc-p4.el
@@ -188,6 +188,11 @@ compare non-open files to the depot version."
   (vc-p4-state file)
   (vc-file-getprop file 'vc-workfile-version))
 
+(defun vc-p4-previous-revision (file rev)
+  (let ((newrev (1- (string-to-number rev))))
+    (when (< 0 newrev)
+      (number-to-string newrev))))
+
 (defun vc-p4-latest-on-branch-p (file)
   "Returns non-nil if the Perforce version of FILE is the head
 revision."