Add a new --rejoin option.

diff --git a/git-subtree.sh b/git-subtree.sh
index 5f8b0f6c598601756a68fe9df5cc065b791627d9..a31b0b2f6a6ebc11e1c21c61a934ddb68d7275da 100755 (executable)
--- a/git-subtree.sh
+++ b/git-subtree.sh
@@ -2,10 +2,10 @@
 #
 # git-subtree.sh: split/join git repositories in subdirectories of this one
 #
-# Copyright (c) 2009 Avery Pennarun <apenwarr@gmail.com>
+# Copyright (C) 2009 Avery Pennarun <apenwarr@gmail.com>
 #
 OPTS_SPEC="\
-git subtree split <revisions> -- <subdir>
+git subtree split [--rejoin] [--onto rev] <commit...> -- <path>
 git subtree merge 
 
 git subtree does foo and bar!
@@ -13,6 +13,8 @@ git subtree does foo and bar!
 h,help   show the help
 q        quiet
 v        verbose
+onto=    existing subtree revision to connect, if any
+rejoin   merge the new branch back into HEAD
 "
 eval $(echo "$OPTS_SPEC" | git rev-parse --parseopt -- "$@" || echo exit $?)
 . git-sh-setup
@@ -20,6 +22,8 @@ require_work_tree
 
 quiet=
 command=
+onto=
+rejoin=
 
 debug()
 {
@@ -42,9 +46,12 @@ assert()
 
 while [ $# -gt 0 ]; do
        opt="$1"
+       debug "option: $1"
        shift
        case "$opt" in
                -q) quiet=1 ;;
+               --onto) onto="$1"; shift ;;
+               --rejoin) rejoin=1 ;;
                --) break ;;
        esac
 done
@@ -93,7 +100,9 @@ cache_set()
 {
        oldrev="$1"
        newrev="$2"
-       if [ "$oldrev" != "latest" -a -e "$cachedir/$oldrev" ]; then
+       if [ "$oldrev" != "latest_old" \
+            -a "$oldrev" != "latest_new" \
+            -a -e "$cachedir/$oldrev" ]; then
                die "cache for $oldrev already exists!"
        fi
        echo "$newrev" >"$cachedir/$oldrev"
@@ -111,12 +120,29 @@ copy_commit()
                read GIT_COMMITTER_NAME
                read GIT_COMMITTER_EMAIL
                read GIT_COMMITTER_DATE
-               export GIT_AUTHOR_NAME GIT_AUTHOR_EMAIL GIT_AUTHOR_DATE
-               export GIT_COMMITTER_NAME GIT_COMMITTER_EMAIL GIT_COMMITTER_DATE
+               export  GIT_AUTHOR_NAME \
+                       GIT_AUTHOR_EMAIL \
+                       GIT_AUTHOR_DATE \
+                       GIT_COMMITTER_NAME \
+                       GIT_COMMITTER_EMAIL \
+                       GIT_COMMITTER_DATE
                git commit-tree "$2" $3  # reads the rest of stdin
        ) || die "Can't copy commit $1"
 }
 
+merge_msg()
+{
+       dir="$1"
+       latest_old="$2"
+       latest_new="$3"
+       cat <<-EOF
+               Split changes from '$dir/' into commit '$latest_new'
+               
+               git-subtree-dir: $dir
+               git-subtree-includes: $latest_old
+       EOF
+}
+
 cmd_split()
 {
        debug "Splitting $dir..."
@@ -140,14 +166,23 @@ cmd_split()
                        newrev=$(copy_commit $rev $tree "$p") || exit $?
                        debug "  newrev is: $newrev"
                        cache_set $rev $newrev
-                       cache_set latest $newrev
+                       cache_set latest_new $newrev
+                       cache_set latest_old $rev
                done || exit $?
        done || exit $?
-       latest=$(cache_get latest)
-       if [ -z "$latest" ]; then
+       latest_new=$(cache_get latest_new)
+       if [ -z "$latest_new" ]; then
                die "No new revisions were found"
        fi
-       echo $latest
+       
+       if [ -n "$rejoin" ]; then
+               debug "Merging split branch into HEAD..."
+               latest_old=$(cache_get latest_old)
+               git merge -s ours \
+                       -m "$(merge_msg $dir $latest_old $latest_new)" \
+                       $latest_new
+       fi
+       echo $latest_new
        exit 0
 }