Merge branch 'sb/submodule-update-dot-branch'

A few updates to "git submodule update".

Use of "| wc -l" break with BSD variant of 'wc'.

* sb/submodule-update-dot-branch:
  t7406: fix breakage on OSX
  submodule update: allow '.' for branch value
  submodule--helper: add remote-branch helper
  submodule-config: keep configured branch around
  submodule--helper: fix usage string for relative-path
  submodule update: narrow scope of local variable
  submodule update: respect depth in subsequent fetches
  t7406: future proof tests with hard coded depth

5 files changed, 132 insertions, 17 deletions

diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
index 6f6d67a469..b09632e468 100644
--- a/builtin/submodule--helper.c
+++ b/builtin/submodule--helper.c
@@ -892,13 +892,64 @@ static int resolve_relative_path(int argc, const char **argv, const char *prefix
 {
 	struct strbuf sb = STRBUF_INIT;
 	if (argc != 3)
-		die("submodule--helper relative_path takes exactly 2 arguments, got %d", argc);
+		die("submodule--helper relative-path takes exactly 2 arguments, got %d", argc);
 
 	printf("%s", relative_path(argv[1], argv[2], &sb));
 	strbuf_release(&sb);
 	return 0;
 }
 
+static const char *remote_submodule_branch(const char *path)
+{
+	const struct submodule *sub;
+	gitmodules_config();
+	git_config(submodule_config, NULL);
+
+	sub = submodule_from_path(null_sha1, path);
+	if (!sub)
+		return NULL;
+
+	if (!sub->branch)
+		return "master";
+
+	if (!strcmp(sub->branch, ".")) {
+		unsigned char sha1[20];
+		const char *refname = resolve_ref_unsafe("HEAD", 0, sha1, NULL);
+
+		if (!refname)
+			die(_("No such ref: %s"), "HEAD");
+
+		/* detached HEAD */
+		if (!strcmp(refname, "HEAD"))
+			die(_("Submodule (%s) branch configured to inherit "
+			      "branch from superproject, but the superproject "
+			      "is not on any branch"), sub->name);
+
+		if (!skip_prefix(refname, "refs/heads/", &refname))
+			die(_("Expecting a full ref name, got %s"), refname);
+		return refname;
+	}
+
+	return sub->branch;
+}
+
+static int resolve_remote_submodule_branch(int argc, const char **argv,
+		const char *prefix)
+{
+	const char *ret;
+	struct strbuf sb = STRBUF_INIT;
+	if (argc != 2)
+		die("submodule--helper remote-branch takes exactly one arguments, got %d", argc);
+
+	ret = remote_submodule_branch(argv[1]);
+	if (!ret)
+		die("submodule %s doesn't exist", argv[1]);
+
+	printf("%s", ret);
+	strbuf_release(&sb);
+	return 0;
+}
+
 struct cmd_struct {
 	const char *cmd;
 	int (*fn)(int, const char **, const char *);
@@ -912,7 +963,8 @@ static struct cmd_struct commands[] = {
 	{"relative-path", resolve_relative_path},
 	{"resolve-relative-url", resolve_relative_url},
 	{"resolve-relative-url-test", resolve_relative_url_test},
-	{"init", module_init}
+	{"init", module_init},
+	{"remote-branch", resolve_remote_submodule_branch}
 };
 
 int cmd_submodule__helper(int argc, const char **argv, const char *prefix)
diff --git a/git-submodule.sh b/git-submodule.sh
index c90dc335d1..b57f87de65 100755
--- a/git-submodule.sh
+++ b/git-submodule.sh
@@ -479,7 +479,8 @@ fetch_in_submodule () (
 	'')
 		git fetch ;;
 	*)
-		git fetch $(get_default_remote) "$2" ;;
+		shift
+		git fetch $(get_default_remote) "$@" ;;
 	esac
 )
 
@@ -588,7 +589,6 @@ cmd_update()
 
 		name=$(git submodule--helper name "$sm_path") || exit
 		url=$(git config submodule."$name".url)
-		branch=$(get_submodule_config "$name" branch master)
 		if ! test -z "$update"
 		then
 			update_module=$update
@@ -614,10 +614,11 @@ cmd_update()
 
 		if test -n "$remote"
 		then
+			branch=$(git submodule--helper remote-branch "$sm_path")
 			if test -z "$nofetch"
 			then
 				# Fetch remote before determining tracking $sha1
-				fetch_in_submodule "$sm_path" ||
+				fetch_in_submodule "$sm_path" $depth ||
 				die "$(eval_gettext "Unable to fetch in submodule path '\$sm_path'")"
 			fi
 			remote_name=$(sanitize_submodule_env; cd "$sm_path" && get_default_remote)
@@ -640,13 +641,13 @@ cmd_update()
 				# Run fetch only if $sha1 isn't present or it
 				# is not reachable from a ref.
 				is_tip_reachable "$sm_path" "$sha1" ||
-				fetch_in_submodule "$sm_path" ||
+				fetch_in_submodule "$sm_path" $depth ||
 				die "$(eval_gettext "Unable to fetch in submodule path '\$displaypath'")"
 
 				# Now we tried the usual fetch, but $sha1 may
 				# not be reachable from any of the refs
 				is_tip_reachable "$sm_path" "$sha1" ||
-				fetch_in_submodule "$sm_path" "$sha1" ||
+				fetch_in_submodule "$sm_path" $depth "$sha1" ||
 				die "$(eval_gettext "Fetched in submodule path '\$displaypath', but it did not contain \$sha1. Direct fetching of that commit failed.")"
 			fi
 
diff --git a/submodule-config.c b/submodule-config.c
index d22a851d27..098085be69 100644
--- a/submodule-config.c
+++ b/submodule-config.c
@@ -59,6 +59,7 @@ static void free_one_config(struct submodule_entry *entry)
 {
 	free((void *) entry->config->path);
 	free((void *) entry->config->name);
+	free((void *) entry->config->branch);
 	free((void *) entry->config->update_strategy.command);
 	free(entry->config);
 }
@@ -199,6 +200,7 @@ static struct submodule *lookup_or_create_by_name(struct submodule_cache *cache,
 	submodule->update_strategy.command = NULL;
 	submodule->fetch_recurse = RECURSE_SUBMODULES_NONE;
 	submodule->ignore = NULL;
+	submodule->branch = NULL;
 	submodule->recommend_shallow = -1;
 
 	hashcpy(submodule->gitmodules_sha1, gitmodules_sha1);
@@ -358,9 +360,16 @@ static int parse_config(const char *var, const char *value, void *data)
 		if (!me->overwrite && submodule->recommend_shallow != -1)
 			warn_multiple_config(me->commit_sha1, submodule->name,
 					     "shallow");
-		else {
+		else
 			submodule->recommend_shallow =
 				git_config_bool(var, value);
+	} else if (!strcmp(item.buf, "branch")) {
+		if (!me->overwrite && submodule->branch)
+			warn_multiple_config(me->commit_sha1, submodule->name,
+					     "branch");
+		else {
+			free((void *)submodule->branch);
+			submodule->branch = xstrdup(value);
 		}
 	}
 
diff --git a/submodule-config.h b/submodule-config.h
index b1fdcc0c33..d05c542d2c 100644
--- a/submodule-config.h
+++ b/submodule-config.h
@@ -15,6 +15,7 @@ struct submodule {
 	const char *url;
 	int fetch_recurse;
 	const char *ignore;
+	const char *branch;
 	struct submodule_update_strategy update_strategy;
 	/* the sha1 blob id of the responsible .gitmodules file */
 	unsigned char gitmodules_sha1[20];
diff --git a/t/t7406-submodule-update.sh b/t/t7406-submodule-update.sh
index 88e9750abb..64f322c4cc 100755
--- a/t/t7406-submodule-update.sh
+++ b/t/t7406-submodule-update.sh
@@ -209,9 +209,42 @@ test_expect_success 'submodule update --remote should fetch upstream changes' '
 	)
 '
 
+test_expect_success 'submodule update --remote should fetch upstream changes with .' '
+	(
+		cd super &&
+		git config -f .gitmodules submodule."submodule".branch "." &&
+		git add .gitmodules &&
+		git commit -m "submodules: update from the respective superproject branch"
+	) &&
+	(
+		cd submodule &&
+		echo line4a >> file &&
+		git add file &&
+		test_tick &&
+		git commit -m "upstream line4a" &&
+		git checkout -b test-branch &&
+		test_commit on-test-branch
+	) &&
+	(
+		cd super &&
+		git submodule update --remote --force submodule &&
+		git -C submodule log -1 --oneline >actual
+		git -C ../submodule log -1 --oneline master >expect
+		test_cmp expect actual &&
+		git checkout -b test-branch &&
+		git submodule update --remote --force submodule &&
+		git -C submodule log -1 --oneline >actual
+		git -C ../submodule log -1 --oneline test-branch >expect
+		test_cmp expect actual &&
+		git checkout master &&
+		git branch -d test-branch &&
+		git reset --hard HEAD^
+	)
+'
+
 test_expect_success 'local config should override .gitmodules branch' '
 	(cd submodule &&
-	 git checkout -b test-branch &&
+	 git checkout test-branch &&
 	 echo line5 >> file &&
 	 git add file &&
 	 test_tick &&
@@ -841,16 +874,35 @@ test_expect_success SYMLINKS 'submodule update can handle symbolic links in pwd'
 '
 
 test_expect_success 'submodule update clone shallow submodule' '
+	test_when_finished "rm -rf super3" &&
+	first=$(git -C cloned submodule status submodule |cut -c2-41) &&
+	second=$(git -C submodule rev-parse HEAD) &&
+	commit_count=$(git -C submodule rev-list --count $first^..$second) &&
 	git clone cloned super3 &&
 	pwd=$(pwd) &&
-	(cd super3 &&
-	 sed -e "s#url = ../#url = file://$pwd/#" <.gitmodules >.gitmodules.tmp &&
-	 mv -f .gitmodules.tmp .gitmodules &&
-	 git submodule update --init --depth=3
-	 (cd submodule &&
-	  test 1 = $(git log --oneline | wc -l)
-	 )
-)
+	(
+		cd super3 &&
+		sed -e "s#url = ../#url = file://$pwd/#" <.gitmodules >.gitmodules.tmp &&
+		mv -f .gitmodules.tmp .gitmodules &&
+		git submodule update --init --depth=$commit_count &&
+		test 1 = $(git -C submodule log --oneline | wc -l)
+	)
+'
+
+test_expect_success 'submodule update clone shallow submodule outside of depth' '
+	test_when_finished "rm -rf super3" &&
+	git clone cloned super3 &&
+	pwd=$(pwd) &&
+	(
+		cd super3 &&
+		sed -e "s#url = ../#url = file://$pwd/#" <.gitmodules >.gitmodules.tmp &&
+		mv -f .gitmodules.tmp .gitmodules &&
+		test_must_fail git submodule update --init --depth=1 2>actual &&
+		test_i18ngrep "Direct fetching of that commit failed." actual &&
+		git -C ../submodule config uploadpack.allowReachableSHA1InWant true &&
+		git submodule update --init --depth=1 >actual &&
+		test 1 = $(git -C submodule log --oneline | wc -l)
+	)
 '
 
 test_expect_success 'submodule update --recursive drops module name before recursing' '