Merge pull request #1222 from scunz/clone_branch

Switch to specified branch during clone

include/git2/clone.h

@@ -57,6 +57,8 @@ GIT_BEGIN_DECL
  *   the origin remote before the fetch is initiated.
  * - `remote_autotag` may be used to specify the autotag setting before the
  *   initial fetch.
+ * - `checkout_branch` gives the name of the branch to checkout. NULL means
+ *   use the remote's HEAD.
  */
 
 typedef struct git_clone_options {
@@ -76,10 +78,11 @@ typedef struct git_clone_options {
 	git_transport *transport;
 	git_remote_callbacks *remote_callbacks;
 	git_remote_autotag_option_t remote_autotag;
+	const char* checkout_branch;
 } git_clone_options;
 
 #define GIT_CLONE_OPTIONS_VERSION 1
-#define GIT_CLONE_OPTIONS_INIT {GIT_CLONE_OPTIONS_VERSION, {GIT_CHECKOUT_OPTS_VERSION, GIT_CHECKOUT_SAFE}}
+#define GIT_CLONE_OPTIONS_INIT {GIT_CLONE_OPTIONS_VERSION, {GIT_CHECKOUT_OPTS_VERSION, GIT_CHECKOUT_SAFE_CREATE}}
 
 /**
  * Clone a remote repository, and checkout the branch pointed to by the remote

src/clone.c

@@ -29,7 +29,7 @@ static int create_branch(
 	const char *name)
 {
 	git_commit *head_obj = NULL;
-	git_reference *branch_ref;
+	git_reference *branch_ref = NULL;
 	int error;
 
 	/* Find the target commit */
@@ -260,6 +260,32 @@ cleanup:
 	return retcode;
 }
 
+static int update_head_to_branch(
+		git_repository *repo,
+		const git_clone_options *options)
+{
+	int retcode;
+	git_buf remote_branch_name = GIT_BUF_INIT;
+	git_reference* remote_ref = NULL;
+	
+	assert(options->checkout_branch);
+
+	if ((retcode = git_buf_printf(&remote_branch_name, GIT_REFS_REMOTES_DIR "%s/%s",
+		options->remote_name, options->checkout_branch)) < 0 )
+		goto cleanup;
+
+	if ((retcode = git_reference_lookup(&remote_ref, repo, git_buf_cstr(&remote_branch_name))) < 0)
+		goto cleanup;
+
+	retcode = update_head_to_new_branch(repo, git_reference_target(remote_ref),
+		options->checkout_branch);
+
+cleanup:
+	git_reference_free(remote_ref);
+	git_buf_free(&remote_branch_name);
+	return retcode;
+}
+
 /*
  * submodules?
  */
@@ -331,8 +357,13 @@ static int setup_remotes_and_fetch(
 						options->fetch_progress_payload)) {
 				/* Create "origin/foo" branches for all remote branches */
 				if (!git_remote_update_tips(origin)) {
+					/* Point HEAD to the requested branch */
+					if (options->checkout_branch) {
+						if (!update_head_to_branch(repo, options))
+							retcode = 0;
+					}
 					/* Point HEAD to the same ref as the remote's head */
-					if (!update_head_to_remote(repo, origin)) {
+					else if (!update_head_to_remote(repo, origin)) {
 						retcode = 0;
 					}
 				}

tests-clar/clone/nonetwork.c

@@ -7,6 +7,8 @@
 
 static git_clone_options g_options;
 static git_repository *g_repo;
+static git_reference* g_ref;
+static git_remote* g_remote;
 
 void test_clone_nonetwork__initialize(void)
 {
@@ -27,6 +29,16 @@ void test_clone_nonetwork__cleanup(void)
 		g_repo = NULL;
 	}
 
+	if (g_ref) {
+		git_reference_free(g_ref);
+		g_ref = NULL;
+	}
+
+	if (g_remote) {
+		git_remote_free(g_remote);
+		g_remote = NULL;
+	}
+
 	cl_fixture_cleanup("./foo");
 }
 
@@ -73,66 +85,51 @@ void test_clone_nonetwork__fail_with_already_existing_but_non_empty_directory(vo
 
 void test_clone_nonetwork__custom_origin_name(void)
 {
-	git_remote *remote;
-
 	g_options.remote_name = "my_origin";
 	cl_git_pass(git_clone(&g_repo, cl_git_fixture_url("testrepo.git"), "./foo", &g_options));
 
-	cl_git_pass(git_remote_load(&remote, g_repo, "my_origin"));
-
-	git_remote_free(remote);
+	cl_git_pass(git_remote_load(&g_remote, g_repo, "my_origin"));
 }
 
 void test_clone_nonetwork__custom_push_url(void)
 {
-	git_remote *remote;
 	const char *url = "http://example.com";
 
 	g_options.pushurl = url;
 	cl_git_pass(git_clone(&g_repo, cl_git_fixture_url("testrepo.git"), "./foo", &g_options));
 
-	cl_git_pass(git_remote_load(&remote, g_repo, "origin"));
-	cl_assert_equal_s(url, git_remote_pushurl(remote));
-
-	git_remote_free(remote);
+	cl_git_pass(git_remote_load(&g_remote, g_repo, "origin"));
+	cl_assert_equal_s(url, git_remote_pushurl(g_remote));
 }
 
 void test_clone_nonetwork__custom_fetch_spec(void)
 {
-	git_remote *remote;
-	git_reference *master;
 	const git_refspec *actual_fs;
 	const char *spec = "+refs/heads/master:refs/heads/foo";
 
 	g_options.fetch_spec = spec;
 	cl_git_pass(git_clone(&g_repo, cl_git_fixture_url("testrepo.git"), "./foo", &g_options));
 
-	cl_git_pass(git_remote_load(&remote, g_repo, "origin"));
-	actual_fs = git_remote_fetchspec(remote);
+	cl_git_pass(git_remote_load(&g_remote, g_repo, "origin"));
+	actual_fs = git_remote_fetchspec(g_remote);
 	cl_assert_equal_s("refs/heads/master", git_refspec_src(actual_fs));
 	cl_assert_equal_s("refs/heads/foo", git_refspec_dst(actual_fs));
 
-	cl_git_pass(git_reference_lookup(&master, g_repo, "refs/heads/foo"));
-	git_reference_free(master);
-
-	git_remote_free(remote);
+	cl_git_pass(git_reference_lookup(&g_ref, g_repo, "refs/heads/foo"));
 }
 
 void test_clone_nonetwork__custom_push_spec(void)
 {
-	git_remote *remote;
 	const git_refspec *actual_fs;
 	const char *spec = "+refs/heads/master:refs/heads/foo";
 
 	g_options.push_spec = spec;
 	cl_git_pass(git_clone(&g_repo, cl_git_fixture_url("testrepo.git"), "./foo", &g_options));
 
-	cl_git_pass(git_remote_load(&remote, g_repo, "origin"));
-	actual_fs = git_remote_pushspec(remote);
+	cl_git_pass(git_remote_load(&g_remote, g_repo, "origin"));
+	actual_fs = git_remote_pushspec(g_remote);
 	cl_assert_equal_s("refs/heads/master", git_refspec_src(actual_fs));
 	cl_assert_equal_s("refs/heads/foo", git_refspec_dst(actual_fs));
-
-	git_remote_free(remote);
 }
 
 void test_clone_nonetwork__custom_autotag(void)
@@ -167,3 +164,14 @@ void test_clone_nonetwork__can_prevent_the_checkout_of_a_standard_repo(void)
 	git_buf_free(&path);
 }
 
+void test_clone_nonetwork__can_checkout_given_branch(void)
+{
+	g_options.checkout_branch = "test";
+	cl_git_pass(git_clone(&g_repo, cl_git_fixture_url("testrepo.git"), "./foo", &g_options));
+
+	cl_assert_equal_i(0, git_repository_head_orphan(g_repo));
+
+	cl_git_pass(git_repository_head(&g_ref, g_repo));
+	cl_assert_equal_s(git_reference_name(g_ref), "refs/heads/test");
+}
+