Added new 'push' command and 2-parameter form of 'add'.

Now you can do:

	git subtree add --prefix=whatever git://wherever branchname

to add a new branch, instead of rather weirdly having to do 'git fetch'
first.  You can also split and push in one step:

	git subtree push --prefix=whatever git://wherever newbranch

(Somewhat cleaned up by apenwarr.)

4 files changed, 77 insertions, 18 deletions

diff --git a/INSTALL b/INSTALL
index 5966dde46c..81ac702ad2 100644
--- a/INSTALL
+++ b/INSTALL
@@ -2,7 +2,16 @@
 HOW TO INSTALL git-subtree
 ==========================
 
-Copy the file 'git-subtree.sh' to /usr/local/bin/git-subtree.
+You simply need to copy the file 'git-subtree.sh' to where
+the rest of the git scripts are stored. 
+
+From the Git bash window just run:
+
+install.sh 
+
+Or if you have the full Cygwin installed, you can use make:
+
+make install
 
 That will make a 'git subtree' (note: space instead of dash) command
 available.  See the file git-subtree.txt for more.
diff --git a/git-subtree.sh b/git-subtree.sh
index e76b45c2dd..501c6dc2f1 100755
--- a/git-subtree.sh
+++ b/git-subtree.sh
@@ -11,6 +11,7 @@ OPTS_SPEC="\
 git subtree add   --prefix=<prefix> <commit>
 git subtree merge --prefix=<prefix> <commit>
 git subtree pull  --prefix=<prefix> <repository> <refspec...>
+git subtree push  --prefix=<prefix> <repository> <refspec...>
 git subtree split --prefix=<prefix> <commit...>
 --
 h,help        show the help
@@ -24,7 +25,7 @@ b,branch=     create a new branch from the split subtree
 ignore-joins  ignore prior --rejoin commits
 onto=         try connecting new tree to an existing one
 rejoin        merge the new branch back into HEAD
- options for 'add', 'merge', and 'pull'
+ options for 'add', 'merge', 'pull' and 'push'
 squash        merge subtree changes as a single commit
 "
 eval $(echo "$OPTS_SPEC" | git rev-parse --parseopt -- "$@" || echo exit $?)
@@ -98,7 +99,7 @@ command="$1"
 shift
 case "$command" in
 	add|merge|pull) default= ;;
-	split) default="--default HEAD" ;;
+	split|push) default="--default HEAD" ;;
 	*) die "Unknown command '$command'" ;;
 esac
 
@@ -115,7 +116,7 @@ esac
 
 dir="$(dirname "$prefix/.")"
 
-if [ "$command" != "pull" ]; then
+if [ "$command" != "pull" -a "$command" != "add" -a "$command" != "push" ]; then
 	revs=$(git rev-parse $default --revs-only "$@") || exit $?
 	dirs="$(git rev-parse --no-revs --no-flags "$@")" || exit $?
 	if [ -n "$dirs" ]; then
@@ -450,10 +451,10 @@ copy_or_skip()
 
 ensure_clean()
 {
-	if ! git diff-index HEAD --exit-code --quiet; then
+	if ! git diff-index HEAD --exit-code --quiet 2>&1; then
 		die "Working tree has modifications.  Cannot add."
 	fi
-	if ! git diff-index --cached HEAD --exit-code --quiet; then
+	if ! git diff-index --cached HEAD --exit-code --quiet 2>&1; then
 		die "Index has modifications.  Cannot add."
 	fi
 }
@@ -463,12 +464,34 @@ cmd_add()
 	if [ -e "$dir" ]; then
 		die "'$dir' already exists.  Cannot add."
 	fi
+
 	ensure_clean
 	
-	set -- $revs
-	if [ $# -ne 1 ]; then
-		die "You must provide exactly one revision.  Got: '$revs'"
+	if [ $# -eq 1 ]; then
+		"cmd_add_commit" "$@"
+	elif [ $# -eq 2 ]; then
+		"cmd_add_repository" "$@"
+	else
+	    say "error: parameters were '$@'"
+	    die "Provide either a refspec or a repository and refspec."
 	fi
+}
+
+cmd_add_repository()
+{
+	echo "git fetch" "$@"
+	repository=$1
+	refspec=$2
+	git fetch "$@" || exit $?
+	revs=FETCH_HEAD
+	set -- $revs
+	cmd_add_commit "$@"
+}
+
+cmd_add_commit()
+{
+	revs=$(git rev-parse $default --revs-only "$@") || exit $?
+	set -- $revs
 	rev="$1"
 	
 	debug "Adding $dir as '$rev'..."
@@ -586,6 +609,7 @@ cmd_split()
 
 cmd_merge()
 {
+	revs=$(git rev-parse $default --revs-only "$@") || exit $?
 	ensure_clean
 	
 	set -- $revs
@@ -623,7 +647,23 @@ cmd_pull()
 	ensure_clean
 	git fetch "$@" || exit $?
 	revs=FETCH_HEAD
-	cmd_merge
+	set -- $revs
+	cmd_merge "$@"
+}
+
+cmd_push()
+{
+	if [ $# -ne 2 ]; then
+	    die "You must provide <repository> <refspec>"
+	fi
+	if [ -e "$dir" ]; then
+	    repository=$1
+	    refspec=$2
+	    echo "git push using: " $repository $refspec
+	    git push $repository $(git subtree split --prefix=$prefix):refs/heads/$refspec
+	else
+	    die "'$dir' must already exist. Try 'git subtree add'."
+	fi
 }
 
 "cmd_$command" "$@"
diff --git a/git-subtree.txt b/git-subtree.txt
index c455f6912b..4f715c640b 100644
--- a/git-subtree.txt
+++ b/git-subtree.txt
@@ -9,10 +9,12 @@ git-subtree - add, merge, and split subprojects stored in subtrees
 SYNOPSIS
 --------
 [verse]
-'git subtree' add   --prefix=<prefix> <commit>
-'git subtree' merge --prefix=<prefix> <commit>
+'git subtree' add   --prefix=<prefix> <repository> <refspec...>
 'git subtree' pull  --prefix=<prefix> <repository> <refspec...>
-'git subtree' split --prefix=<prefix> <commit...>
+'git subtree' push  --prefix=<prefix> <repository> <refspec...>
+'git subtree' add   --prefix=<prefix> <refspec>
+'git subtree' merge --prefix=<prefix> <refspec>
+'git subtree' split --prefix=<prefix> <refspec...>
          
 
 DESCRIPTION
@@ -60,11 +62,11 @@ COMMANDS
 --------
 add::
 	Create the <prefix> subtree by importing its contents
-	from the given commit.  A new commit is created
-	automatically, joining the imported project's history
-	with your own.  With '--squash', imports only a single
-	commit from the subproject, rather than its entire
-	history.
+	from the given <refspec> or <repository> and remote <refspec>.
+	A new commit is created	automatically, joining the imported
+	project's history with your own.  With '--squash', imports
+	only a single commit from the subproject, rather than its
+	entire history.
 
 merge::
 	Merge recent changes up to <commit> into the <prefix>
@@ -84,6 +86,12 @@ pull::
 	Exactly like 'merge', but parallels 'git pull' in that
 	it fetches the given commit from the specified remote
 	repository.
+	
+push::
+	Does a 'split' (see above) using the <prefix> supplied
+	and then does a 'git push' to push the result to the 
+	repository and refspec. This can be used to push your
+	subtree to different branches of the remote repository.
 
 split::
 	Extract a new, synthetic project history from the
diff --git a/install.sh b/install.sh
new file mode 100644
index 0000000000..1f87a62434
--- /dev/null
+++ b/install.sh
@@ -0,0 +1,2 @@
+# copy Git to where the rest of the Git scripts are found.
+cp git-subtree.sh "$(git --exec-path)"/git-subtree
\ No newline at end of file