submodule: allow runtime enabling extensions.submodulePathConfig

Add a new config `init.defaultSubmodulePathConfig` which allows
enabling `extensions.submodulePathConfig` for new submodules by
default (those created via git init or clone).

Important: setting init.defaultSubmodulePathConfig = true does
not globally enable `extensions.submodulePathConfig`. Existing
repositories will still have the extension disabled and will
require migration (for example via git submodule--helper command
added in the next commit).

Suggested-by: Patrick Steinhardt <ps@pks.im>
Suggested-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 10 insertions, 0 deletions

diff --git a/setup.c b/setup.c
index 207fa36e10..3f91a4aaec 100644
--- a/setup.c
+++ b/setup.c
@@ -2228,6 +2228,7 @@ void initialize_repository_version(int hash_algo,
 {
 	struct strbuf repo_version = STRBUF_INIT;
 	int target_version = GIT_REPO_VERSION;
+	int default_submodule_path_config = 0;
 
 	/*
 	 * Note that we initialize the repository version to 1 when the ref
@@ -2266,6 +2267,15 @@ void initialize_repository_version(int hash_algo,
 		clear_repository_format(&repo_fmt);
 	}
 
+	repo_config_get_bool(the_repository, "init.defaultSubmodulePathConfig",
+			     &default_submodule_path_config);
+	if (default_submodule_path_config) {
+		/* extensions.submodulepathconfig requires at least version 1 */
+		if (target_version == 0)
+			target_version = 1;
+		repo_config_set(the_repository, "extensions.submodulepathconfig", "true");
+	}
+
 	strbuf_addf(&repo_version, "%d", target_version);
 	repo_config_set(the_repository, "core.repositoryformatversion", repo_version.buf);