[PATCHv2] builtin/clone: support submodule groups

@@ -209,6 +209,19 @@ objects from the source repository into a pack in the cloned repository.
 	repository does not have a worktree/checkout (i.e. if any of
 	`--no-checkout`/`-n`, `--bare`, or `--mirror` is given)
 
+--group::
+	After the clone is created, all submodules which are part of the
+	given groups are cloned. To specify multiple groups, you can either
+	give the group argument multiple times or comma separate the groups.
+	This option will be recorded in the `submodule.groups` config,
+	which will affect the behavior of other submodule related commands,
+	such as `git submodule update`.
+	This option implies recursive submodule checkout. If you don't
+	want to recurse into nested submodules, you need to specify
+	`--no-recursive`. The group selection will be passed on recursively,
+	i.e. if a submodule is cloned because of group membership, its
+	submodules will be cloned according to group membership, too.
+
 --separate-git-dir=<git dir>::
 	Instead of placing the cloned repository where it is supposed
 	to be, place the cloned repository at the specified directory,

@@ -39,7 +39,7 @@ static const char * const builtin_clone_usage[] = {
 };
 
 static int option_no_checkout, option_bare, option_mirror, option_single_branch = -1;
-static int option_local = -1, option_no_hardlinks, option_shared, option_recursive;
+static int option_local = -1, option_no_hardlinks, option_shared, option_recursive = -1;
 static char *option_template, *option_depth;
 static char *option_origin = NULL;
 static char *option_branch = NULL;

@@ -51,6 +51,7 @@ static struct string_list option_config;
 static struct string_list option_reference;
 static int option_dissociate;
 static int max_jobs = -1;
+static struct string_list submodule_groups;
 
 static struct option builtin_clone_options[] = {
 	OPT__VERBOSITY(&option_verbosity),

@@ -95,6 +96,8 @@ static struct option builtin_clone_options[] = {
 		   N_("separate git dir from working tree")),
 	OPT_STRING_LIST('c', "config", &option_config, N_("key=value"),
 			N_("set config inside the new repository")),
+	OPT_STRING_LIST('g', "group", &submodule_groups, N_("group"),
+			N_("clone specific submodule groups")),
 	OPT_END()
 };
 

@@ -723,9 +726,18 @@ static int checkout(void)
 	err |= run_hook_le(NULL, "post-checkout", sha1_to_hex(null_sha1),
 			   sha1_to_hex(sha1), "1", NULL);
 
-	if (!err && option_recursive) {
+	if (err)
+		goto out;
+
+	if (option_recursive || submodule_groups.nr > 0) {
 		struct argv_array args = ARGV_ARRAY_INIT;
-		argv_array_pushl(&args, "submodule", "update", "--init", "--recursive", NULL);
+		argv_array_pushl(&args, "submodule", "update", "--init", NULL);
+
+		if (option_recursive)
+			argv_array_pushf(&args, "--recursive");
+
+		if (submodule_groups.nr > 0)
+			argv_array_pushf(&args, "--groups");
 
 		if (max_jobs != -1)
 			argv_array_pushf(&args, "--jobs=%d", max_jobs);

@@ -733,7 +745,7 @@ static int checkout(void)
 		err = run_command_v_opt(args.argv, RUN_GIT_CMD);
 		argv_array_clear(&args);
 	}
-
+out:
 	return err;
 }
 

@@ -863,6 +875,24 @@ int cmd_clone(int argc, const char **argv, const char *prefix)
 			die(_("--bare and --separate-git-dir are incompatible."));
 		option_no_checkout = 1;
 	}
+	if (option_recursive == -1) {
+		if (submodule_groups.nr > 0)
+			option_recursive = 1; /* submodule groups implies recursive */
+		else
+			option_recursive = 0; /* preserve historical default */
+	}
+	if (submodule_groups.nr > 0) {
+		int first_item = 1;
+		struct string_list_item *item;
+		struct strbuf sb = STRBUF_INIT;
+		strbuf_addstr(&sb, "submodule.groups=");
+		for_each_string_list_item(item, &submodule_groups) {
+			strbuf_addf(&sb, "%s%s", first_item ? "" : ",", item->string);
+			first_item = 0;
+		}
+		if (submodule_groups.nr > 0)
+			string_list_append(&option_config, strbuf_detach(&sb, 0));
+	}
 
 	if (!option_origin)
 		option_origin = "origin";

@@ -611,6 +611,7 @@ cmd_deinit()
 #
 cmd_update()
 {
+	groups=
 	# parse $args after "submodule ... update".
 	while test $# -ne 0
 	do

@@ -650,6 +651,9 @@ cmd_update()
 		--checkout)
 			update="checkout"
 			;;
+		--groups)
+			groups=1
+			;;
 		--depth)
 			case "$2" in '') usage ;; esac
 			depth="--depth=$2"

@@ -691,6 +695,7 @@ cmd_update()
 		${update:+--update "$update"} \
 		${reference:+--reference "$reference"} \
 		${depth:+--depth "$depth"} \
+		${groups:+--groups} \
 		${jobs:+$jobs} \
 		"$@" | {
 	err=

@@ -1049,4 +1049,73 @@ test_expect_success 'submodule init --group works' '
 	)
 '
 
+cat <<EOF > expected
+submodule
+-submodule1
+EOF
+
+test_expect_success 'submodule update --groups works' '
+	test_when_finished "rm -rf super super_clone" &&
+	mkdir super &&
+	pwd=$(pwd) &&
+	(
+		cd super &&
+		git init &&
+		git submodule add --group groupA file://"$pwd"/example2 submodule &&
+		git submodule add file://"$pwd"/example2 submodule1 &&
+		git commit -a -m "create repository with 2 submodules, one is in a group"
+	) &&
+	git clone super super_clone &&
+	(
+		cd super_clone &&
+		git config submodule.groups groupA &&
+		git submodule init  &&
+		git submodule update --groups &&
+		git submodule status |cut -c1,42-52 | tr -d " " >../actual
+	) &&
+	test_cmp actual expected
+'
+
+test_expect_success 'submodule update --init --groups works' '
+	test_when_finished "rm -rf super super_clone" &&
+	mkdir super &&
+	pwd=$(pwd) &&
+	(
+		cd super &&
+		git init &&
+		git submodule add --group groupA file://"$pwd"/example2 submodule &&
+		git submodule add file://"$pwd"/example2 submodule1 &&
+		git commit -a -m "create repository with 2 submodules, one is in a group"
+	) &&
+	git clone super super_clone &&
+	(
+		cd super_clone &&
+		git config submodule.groups groupA &&
+		git submodule update --init --groups &&
+		git submodule status |cut -c1,42-52 | tr -d " " >../actual
+	) &&
+	test_cmp actual expected
+'
+
+test_expect_success 'clone --group works' '
+	test_when_finished "rm -rf super super_clone" &&
+	mkdir super &&
+	pwd=$(pwd) &&
+	(
+		cd super &&
+		git init &&
+		git submodule add --group groupA file://"$pwd"/example2 submodule &&
+		git submodule add file://"$pwd"/example2 submodule1 &&
+		git commit -a -m "create repository with 2 submodules, one is in a group"
+	) &&
+	git clone --group groupA super super_clone &&
+	(
+		cd super_clone &&
+		test_pause
+		git submodule status |cut -c1,42-52 | tr -d " " >../actual
+	) &&
+	test_cmp actual expected
+'
+
+
 test_done

@@ -801,4 +801,36 @@ test_expect_success 'git clone passes the parallel jobs config on to submodules'
 	rm -rf super4
 '
 
+cat >expect <<-EOF &&
+-deeper/submodule
+-merging
+-moved/sub module
+-none
+-rebasing
+-submodule
+-submodule1
+EOF
+
+# none, merging rebasing, submodule1, submodule
+test_expect_success 'git clone works with submodule groups.' '
+	test_when_finished "rm -rf super5" &&
+	(
+		cd super &&
+		git config -f .gitmodules  submodule.submodule.groups default &&
+		git config -f .gitmodules  submodule.submodule1.groups "default,testing" &&
+		git config -f .gitmodules  submodule.none.groups testing &&
+		git commit -a -m "assigning groups to submodules"
+	) &&
+	git clone --group default --group testing super super5 &&
+	(
+		cd super5 &&
+		git submodule status |cut -c1,43- >../actual
+	) &&
+	test_cmp actual expect
+'
+
+test_expect_success 'git submodule update --groups' '
+	true
+'
+
 test_done