git-p4: Unset P4DIFF environment variable when using 'p4 -du diff'

diff --git a/git-svn.perl b/git-svn.perl
index 1195569529401fd1c62414c8683a6b577721c1c7..d8b38c9a47c0b77dd55781a66e42e4dec26fd4b7 100755 (executable)
--- a/git-svn.perl
+++ b/git-svn.perl
@@ -522,7 +522,8 @@ sub cmd_dcommit {
 }
 
 sub cmd_find_rev {
-       my $revision_or_hash = shift;
+       my $revision_or_hash = shift or die "SVN or git revision required ",
+                                           "as a command-line argument\n";
        my $result;
        if ($revision_or_hash =~ /^r\d+$/) {
                my $head = shift;