rebase: use @{upstream} if no upstream specified

diff --git a/git-rebase.sh b/git-rebase.sh
index be9ec2a1f79cc8d61e7255a1609577fc7c2c29f2..a040ab51cc68f4ee8d173eda17907447360e4a73 100755 (executable)
--- a/git-rebase.sh
+++ b/git-rebase.sh
@@ -3,7 +3,7 @@
 # Copyright (c) 2005 Junio C Hamano.
 #
 
-USAGE='[--interactive | -i] [-v] [--force-rebase | -f] [--no-ff] [--onto <newbase>] (<upstream>|--root) [<branch>] [--quiet | -q]'
+USAGE='[--interactive | -i] [-v] [--force-rebase | -f] [--no-ff] [--onto <newbase>] [<upstream>|--root] [<branch>] [--quiet | -q]'
 LONG_USAGE='git-rebase replaces <branch> with a new branch of the
 same name.  When the --onto option is provided the new branch starts
 out with a HEAD equal to <newbase>, otherwise it is equal to <upstream>
@@ -345,8 +345,6 @@ and run me again.  I am stopping in case you still have something
 valuable there.'
 fi
 
-test $# -eq 0 && test -z "$rebase_root" && usage
-
 if test -n "$interactive_rebase"
 then
        type=interactive
@@ -362,9 +360,20 @@ fi
 
 if test -z "$rebase_root"
 then
-       # The upstream head must be given.  Make sure it is valid.
-       upstream_name="$1"
-       shift
+       case "$#" in
+       0)
+               if ! upstream_name=$(git rev-parse --symbolic-full-name \
+                       --verify -q @{upstream} 2>/dev/null)
+               then
+                       . git-parse-remote
+                       error_on_missing_default_upstream "rebase" "rebase" \
+                               "against" "git rebase <upstream branch>"
+               fi
+               ;;
+       *)      upstream_name="$1"
+               shift
+               ;;
+       esac
        upstream=`git rev-parse --verify "${upstream_name}^0"` ||
        die "invalid upstream $upstream_name"
        upstream_arg="$upstream_name"