# Copyright (c) 2005 Junio C Hamano.
#
+USAGE='<upstream> [<head>]'
. git-sh-setup
-# The other head is given
-other=$(git-rev-parse --verify "$1^0") || exit
+case $# in 1|2) ;; *) usage ;; esac
+
+# Make sure we do not have .dotest
+if mkdir .dotest
+then
+ rmdir .dotest
+else
+ echo >&2 '
+It seems that I cannot create a .dotest directory, and I wonder if you
+are in the middle of patch application or another rebase. If that is not
+the case, please rm -fr .dotest and run me again. I am stopping in case
+you still have something valuable there.'
+ exit 1
+fi
# The tree must be really really clean.
git-update-index --refresh || exit
diff=$(git-diff-index --cached --name-status -r HEAD)
-case "$different" in
+case "$diff" in
?*) echo "$diff"
exit 1
;;
esac
+# The other head is given. Make sure it is valid.
+other=$(git-rev-parse --verify "$1^0") || usage
+
+# Make sure the branch to rebase is valid.
+head=$(git-rev-parse --verify "${2-HEAD}^0") || exit
+
# If the branch to rebase is given, first switch to it.
case "$#" in
2)
- git-checkout "$2" || exit
+ git-checkout "$2" || usage
esac
+mb=$(git-merge-base "$other" "$head")
+
+# Check if we are already based on $other.
+if test "$mb" = "$other"
+then
+ echo >&2 "Current branch `git-symbolic-ref HEAD` is up to date."
+ exit 0
+fi
+
# Rewind the head to "$other"
git-reset --hard "$other"
+
+# If the $other is a proper descendant of the tip of the branch, then
+# we just fast forwarded.
+if test "$mb" = "$head"
+then
+ echo >&2 "Fast-forwarded $head to $other."
+ exit 0
+fi
+
git-format-patch -k --stdout --full-index "$other" ORIG_HEAD |
git am --binary -3 -k