builtin/submodule--helper: add gitdir command

This exposes the gitdir name computed by submodule_name_to_gitdir()
internally, to make it easier for users and tests to interact with it.

Next commit will add a gitdir configuration, so this helper can also be
used to easily query that config or validate any gitdir path the user
sets (submodule_name_to_git_dir now runs the validation logic, since
our previous commit).

Based-on-patch-by: Brandon Williams <bwilliams.eng@gmail.com>
Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
index fc10ace5a847f1cb2d2ab8b2d7f3b6a139f22431..7ea82d7fa243e4b6e34512d5b41f5e28184752d2 100644 (file)
--- a/builtin/submodule--helper.c
+++ b/builtin/submodule--helper.c
@@ -1208,6 +1208,22 @@ static int module_summary(int argc, const char **argv, const char *prefix,
        return ret;
 }
 
+static int module_gitdir(int argc, const char **argv, const char *prefix UNUSED,
+                        struct repository *repo)
+{
+       struct strbuf gitdir = STRBUF_INIT;
+
+       if (argc != 2)
+               usage(_("git submodule--helper gitdir <name>"));
+
+       submodule_name_to_gitdir(&gitdir, repo, argv[1]);
+
+       printf("%s\n", gitdir.buf);
+
+       strbuf_release(&gitdir);
+       return 0;
+}
+
 struct sync_cb {
        const char *prefix;
        const char *super_prefix;
@@ -3587,6 +3603,7 @@ int cmd_submodule__helper(int argc,
                NULL
        };
        struct option options[] = {
+               OPT_SUBCOMMAND("gitdir", &fn, module_gitdir),
                OPT_SUBCOMMAND("clone", &fn, module_clone),
                OPT_SUBCOMMAND("add", &fn, module_add),
                OPT_SUBCOMMAND("update", &fn, module_update),