Fix "git-diff-script A B"

When "git-diff-script A..B" notation was introduced, it ended up breaking
the traditional two revisions notation.

[jc: there are other issues with the current "git diff" I would like to
 address, but they would be left to later rounds.  For example, -M and -p flags
 should not be hardcoded default, and it shouldn't be too hard to rewrite
 the script without using shell arrays.]

Signed-off-by: Junio C Hamano <junkio@cox.net>

diff --git a/git-diff-script b/git-diff-script
index 926f594..99ff264 100755 (executable)
--- a/git-diff-script
+++ b/git-diff-script
@@ -8,8 +8,14 @@ case "${#rev[*]}" in
 1)
        git-diff-cache -M -p "$@";;
 2)
-       begin=$(echo "${rev[1]}" | tr -d '^')
-       end="${rev[0]}"
+       case "${rev[1]}" in
+       ^?*)
+               begin=$(echo "${rev[1]}" | tr -d '^')
+               end="${rev[0]}" ;;
+       *)
+               begin="${rev[0]}"
+               end="${rev[1]}" ;;
+       esac
        git-diff-tree -M -p $flags $begin $end $files;;
 *)
        echo "I don't understand"