push: propagate remote and refspec with --recurse-submodules

Teach "push --recurse-submodules" to propagate, if given a name as remote, the
provided remote and refspec recursively to the pushes performed in the
submodules. The push will therefore only succeed if all submodules have a
remote with such a name configured.

Note that "push --recurse-submodules" with a path or URL as remote will not
propagate the remote or refspec and instead use the default remote and refspec
configured in the submodule, preserving the current behavior.

Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

submodule.c

@@ -14,6 +14,7 @@
 #include "blob.h"
 #include "thread-utils.h"
 #include "quote.h"
+#include "remote.h"
 #include "worktree.h"
 
 static int config_fetch_recurse_submodules = RECURSE_SUBMODULES_ON_DEMAND;
@@ -783,6 +784,8 @@ int find_unpushed_submodules(struct sha1_array *commits,
 }
 
 static int push_submodule(const char *path,
+			  const struct remote *remote,
+			  const char **refspec, int refspec_nr,
 			  const struct string_list *push_options,
 			  int dry_run)
 {
@@ -801,6 +804,14 @@ static int push_submodule(const char *path,
 				argv_array_pushf(&cp.args, "--push-option=%s",
 						 item->string);
 		}
+
+		if (remote->origin != REMOTE_UNCONFIGURED) {
+			int i;
+			argv_array_push(&cp.args, remote->name);
+			for (i = 0; i < refspec_nr; i++)
+				argv_array_push(&cp.args, refspec[i]);
+		}
+
 		prepare_submodule_repo_env(&cp.env_array);
 		cp.git_cmd = 1;
 		cp.no_stdin = 1;
@@ -813,21 +824,67 @@ static int push_submodule(const char *path,
 	return 1;
 }
 
+/*
+ * Perform a check in the submodule to see if the remote and refspec work.
+ * Die if the submodule can't be pushed.
+ */
+static void submodule_push_check(const char *path, const struct remote *remote,
+				 const char **refspec, int refspec_nr)
+{
+	struct child_process cp = CHILD_PROCESS_INIT;
+	int i;
+
+	argv_array_push(&cp.args, "submodule--helper");
+	argv_array_push(&cp.args, "push-check");
+	argv_array_push(&cp.args, remote->name);
+
+	for (i = 0; i < refspec_nr; i++)
+		argv_array_push(&cp.args, refspec[i]);
+
+	prepare_submodule_repo_env(&cp.env_array);
+	cp.git_cmd = 1;
+	cp.no_stdin = 1;
+	cp.no_stdout = 1;
+	cp.dir = path;
+
+	/*
+	 * Simply indicate if 'submodule--helper push-check' failed.
+	 * More detailed error information will be provided by the
+	 * child process.
+	 */
+	if (run_command(&cp))
+		die("process for submodule '%s' failed", path);
+}
+
 int push_unpushed_submodules(struct sha1_array *commits,
-			     const char *remotes_name,
+			     const struct remote *remote,
+			     const char **refspec, int refspec_nr,
 			     const struct string_list *push_options,
 			     int dry_run)
 {
 	int i, ret = 1;
 	struct string_list needs_pushing = STRING_LIST_INIT_DUP;
 
-	if (!find_unpushed_submodules(commits, remotes_name, &needs_pushing))
+	if (!find_unpushed_submodules(commits, remote->name, &needs_pushing))
 		return 1;
 
+	/*
+	 * Verify that the remote and refspec can be propagated to all
+	 * submodules.  This check can be skipped if the remote and refspec
+	 * won't be propagated due to the remote being unconfigured (e.g. a URL
+	 * instead of a remote name).
+	 */
+	if (remote->origin != REMOTE_UNCONFIGURED)
+		for (i = 0; i < needs_pushing.nr; i++)
+			submodule_push_check(needs_pushing.items[i].string,
+					     remote, refspec, refspec_nr);
+
+	/* Actually push the submodules */
 	for (i = 0; i < needs_pushing.nr; i++) {
 		const char *path = needs_pushing.items[i].string;
 		fprintf(stderr, "Pushing submodule '%s'\n", path);
-		if (!push_submodule(path, push_options, dry_run)) {
+		if (!push_submodule(path, remote, refspec, refspec_nr,
+				    push_options, dry_run)) {
 			fprintf(stderr, "Unable to push submodule '%s'\n", path);
 			ret = 0;
 		}

submodule.h

@@ -4,6 +4,7 @@
 struct diff_options;
 struct argv_array;
 struct sha1_array;
+struct remote;
 
 enum {
 	RECURSE_SUBMODULES_ONLY = -5,
@@ -91,7 +92,8 @@ extern int find_unpushed_submodules(struct sha1_array *commits,
 				    const char *remotes_name,
 				    struct string_list *needs_pushing);
 extern int push_unpushed_submodules(struct sha1_array *commits,
-				    const char *remotes_name,
+				    const struct remote *remote,
+				    const char **refspec, int refspec_nr,
 				    const struct string_list *push_options,
 				    int dry_run);
 extern void connect_work_tree_and_git_dir(const char *work_tree, const char *git_dir);

t/t5531-deep-submodule-push.sh

@@ -475,4 +475,56 @@ test_expect_success 'push only unpushed submodules recursively' '
 	test_cmp expected_pub actual_pub
 '
 
+test_expect_success 'push propagating the remotes name to a submodule' '
+	git -C work remote add origin ../pub.git &&
+	git -C work remote add pub ../pub.git &&
+
+	> work/gar/bage/junk10 &&
+	git -C work/gar/bage add junk10 &&
+	git -C work/gar/bage commit -m "Tenth junk" &&
+	git -C work add gar/bage &&
+	git -C work commit -m "Tenth junk added to gar/bage" &&
+
+	# Fails when submodule does not have a matching remote
+	test_must_fail git -C work push --recurse-submodules=on-demand pub master &&
+	# Succeeds when submodules has matching remote and refspec
+	git -C work push --recurse-submodules=on-demand origin master &&
+
+	git -C submodule.git rev-parse master >actual_submodule &&
+	git -C pub.git rev-parse master >actual_pub &&
+	git -C work/gar/bage rev-parse master >expected_submodule &&
+	git -C work rev-parse master >expected_pub &&
+	test_cmp expected_submodule actual_submodule &&
+	test_cmp expected_pub actual_pub
+'
+
+test_expect_success 'push propagating refspec to a submodule' '
+	> work/gar/bage/junk11 &&
+	git -C work/gar/bage add junk11 &&
+	git -C work/gar/bage commit -m "Eleventh junk" &&
+
+	git -C work checkout branch2 &&
+	git -C work add gar/bage &&
+	git -C work commit -m "updating gar/bage in branch2" &&
+
+	# Fails when submodule does not have a matching branch
+	test_must_fail git -C work push --recurse-submodules=on-demand origin branch2 &&
+	# Fails when refspec includes an object id
+	test_must_fail git -C work push --recurse-submodules=on-demand origin \
+		"$(git -C work rev-parse branch2):refs/heads/branch2" &&
+	# Fails when refspec includes 'HEAD' as it is unsupported at this time
+	test_must_fail git -C work push --recurse-submodules=on-demand origin \
+		HEAD:refs/heads/branch2 &&
+
+	git -C work/gar/bage branch branch2 master &&
+	git -C work push --recurse-submodules=on-demand origin branch2 &&
+
+	git -C submodule.git rev-parse branch2 >actual_submodule &&
+	git -C pub.git rev-parse branch2 >actual_pub &&
+	git -C work/gar/bage rev-parse branch2 >expected_submodule &&
+	git -C work rev-parse branch2 >expected_pub &&
+	test_cmp expected_submodule actual_submodule &&
+	test_cmp expected_pub actual_pub
+'
+
 test_done

transport.c

@@ -1030,7 +1030,8 @@ int transport_push(struct transport *transport,
 					sha1_array_append(&commits, ref->new_oid.hash);
 
 			if (!push_unpushed_submodules(&commits,
-						      transport->remote->name,
+						      transport->remote,
+						      refspec, refspec_nr,
 						      transport->push_options,
 						      pretend)) {
 				sha1_array_clear(&commits);