1 files changed, 118 insertions, 0 deletions
diff --git a/git-follow/git-rebase-subtree.in b/git-follow/git-rebase-subtree.in
new file mode 100644
index 0000000..d2422ab
--- /dev/null
+++ b/git-follow/git-rebase-subtree.in
@@ -0,0 +1,118 @@
+#!/bin/sh
+#
+
+unset CDPATH
+SED="${SED-sed}"
+
+self=`basename "$0"`
+selfdir=`dirname "$0"`
+selfdir=`cd "$selfdir" && pwd`
+. "$selfdir/git-ndim-sh"
+
+SUBDIRECTORY_OK="yes"
+USAGE="<command> [params...]"
+
+LONG_USAGE="\
+Let a local subtree of branches follow a remote origin without too much merging.
+For more details, see the ${self}(1) man page."
+. git-sh-setup
+
+require_work_tree
+
+# Abort on error
+set -e
+
+
+cmd() {
+    echo "CMD>" "$@"
+    gitk --all
+    "$@"
+}
+
+
+gf_init() {
+    echo "$self: Examining configuration"
+    git config follow.tree | while read from to restofline; do
+	if test "x#" = "x$(echo "$from" | sed -n '1s/^\(.\).*/\1/p')"; then continue; fi
+	echo ""
+	echo "  From: $from"
+	echo "    To: $to"
+    done
+}
+
+gf_branch() {
+    branch="$1"
+    newbranch="follow-old/$branch"
+    if git-rev-parse --verify "$branch" > /dev/null 2>&1; then
+	# valid branch
+	if git-rev-parse --verify "$newbranch" > /dev/null 2>&1; then
+	    : # branch already exists, do nothing
+	else
+	    cmd git-branch "${newbranch}" "${branch}"
+	fi
+    else
+	echo "$self: gf_branch called with invalid branch \"$branch\"" >&2
+	exit 1
+    fi
+}
+
+
+gf_rmbranch() {
+    branch="$1"
+    newbranch="follow-old/$branch"
+    if git-rev-parse --verify "$branch" > /dev/null 2>&1; then
+	if git-rev-parse --verify "$newbranch" > /dev/null 2>&1; then
+	    cmd git-branch -D "${newbranch}"
+	fi
+    fi
+}
+
+
+gf_rebase_tree() {
+    newroot="$1"
+    test "x$newroot" = "x" && die "Need <newroot> parameter"
+    oldroot="$2"
+    test "x$oldroot" = "x" && die "Need <oldroot> parameter"
+    echo
+    echo "$self: Preparing subtree rebase"
+    git config follow.tree | while read from to restofline; do
+	if test "x#" = "x$(echo "$from" | sed -n '1s/^\(.\).*/\1/p')"; then continue; fi
+	gf_branch "$from"
+	gf_branch "$to"
+    done
+    gitk --all
+    echo
+    echo "$self: Executing subtree rebase"
+    git config follow.tree | while read from to restofline; do
+	if test "x#" = "x$(echo "$from" | sed -n '1s/^\(.\).*/\1/p')"; then continue; fi
+	cmd git-rebase --onto "$from" "follow-old/$from" "$to"
+    done
+    gitk --all
+    echo
+    echo "$self: Cleaning up after subtree rebase"
+    git config follow.tree | while read from to restofline; do
+	if test "x#" = "x$(echo "$from" | sed -n '1s/^\(.\).*/\1/p')"; then continue; fi
+	gf_rmbranch "$from"
+	gf_rmbranch "$to"
+    done
+    gitk --all
+}
+
+
+# The great command case
+command="$1"
+if shift; then
+    case "$command" in
+	rebase-subtree)
+	    gf_init
+	    gf_rebase_tree "$@"
+	    ;;
+	*)
+	    die "Invalid command line parameter: \"$command\""
+	    ;;
+    esac
+else
+    gf_init
+fi
+
+# End of file.