[PATCH] Add option -b/--branch to clone for select a new HEAD

@@ -127,6 +127,10 @@ objects from the source repository into a pack in the cloned repository.
 	Instead of using the remote name 'origin' to keep track
 	of the upstream repository, use <name>.
 
+--branch <name>::
+-b <name>::
+	Instead of using the remote HEAD as master, use <name> branch.
+
 --upload-pack <upload-pack>::
 -u <upload-pack>::
 	When given, and the repository to clone from is accessed

@@ -41,6 +41,7 @@ static int option_quiet, option_no_checkout, option_bare, option_mirror;
 static int option_local, option_no_hardlinks, option_shared;
 static char *option_template, *option_reference, *option_depth;
 static char *option_origin = NULL;
+static char *option_branch = NULL;
 static char *option_upload_pack = "git-upload-pack";
 static int option_verbose;
 

@@ -65,6 +66,8 @@ static struct option builtin_clone_options[] = {
 		   "reference repository"),
 	OPT_STRING('o', "origin", &option_origin, "branch",
 		   "use <branch> instead of 'origin' to track upstream"),
+	OPT_STRING('b', "branch", &option_branch, "branch",
+		   "use <branch> from 'origin' as HEAD"),
 	OPT_STRING('u', "upload-pack", &option_upload_pack, "path",
 		   "path to git-upload-pack on the remote"),
 	OPT_STRING(0, "depth", &option_depth, "depth",

@@ -347,8 +350,8 @@ int cmd_clone(int argc, const char **argv, const char *prefix)
 	const char *repo_name, *repo, *work_tree, *git_dir;
 	char *path, *dir;
 	int dest_exists;
-	const struct ref *refs, *head_points_at, *remote_head, *mapped_refs;
-	struct strbuf key = STRBUF_INIT, value = STRBUF_INIT;
+	const struct ref *refs, *head_points_at, *remote_head = NULL, *mapped_refs;
+	struct strbuf key = STRBUF_INIT, value = STRBUF_INIT, branch_head = STRBUF_INIT;
 	struct strbuf branch_top = STRBUF_INIT, reflog_msg = STRBUF_INIT;
 	struct transport *transport = NULL;
 	char *src_ref_prefix = "refs/heads/";

@@ -518,7 +521,21 @@ int cmd_clone(int argc, const char **argv, const char *prefix)
 
 		mapped_refs = write_remote_refs(refs, refspec, reflog_msg.buf);
 
-		remote_head = find_ref_by_name(refs, "HEAD");
+		if (option_branch) {
+			strbuf_addf(&branch_head, "%s%s", src_ref_prefix, option_branch);
+
+			remote_head = find_ref_by_name(refs, branch_head.buf);
+		}
+
+		if (!remote_head) {
+			if (option_branch)
+				warning("Remote branch %s not found in upstream %s"
+					", using HEAD instead",
+					option_branch, option_origin);
+
+			remote_head = find_ref_by_name(refs, "HEAD");
+		}
+
 		head_points_at = guess_remote_head(remote_head, mapped_refs, 0);
 	}
 	else {

@@ -0,0 +1,31 @@
+#!/bin/sh
+
+test_description='branch clone options'
+. ./test-lib.sh
+
+test_expect_success 'setup' '
+
+	mkdir parent &&
+	(cd parent && git init &&
+	 echo one >file && git add file &&
+	 git commit -m one && git checkout -b two &&
+	 echo two >f && git add f && git commit -m two &&
+	 git checkout master)
+
+'
+
+test_expect_success 'clone' '
+
+	git clone parent clone &&
+	(cd clone && git rev-parse --verify refs/remotes/origin/master)
+
+'
+
+test_expect_success 'clone -b' '
+
+	git clone -b two parent clone-b &&
+	(cd clone-b && test $(git rev-parse --verify HEAD) = $(git rev-parse --verify refs/remotes/origin/two))
+
+'
+
+test_done