Re: git submodules implementation question

From: Junio C Hamano <gitster@pobox.com>
Date: Sep 1, 2016, 04:09 UTC
Message-ID: <xmqqk2ewxnui.fsf@gitster.mtv.corp.google.com>
In-Reply-To: <xmqq7faw3n5w.fsf@gitster.mtv.corp.google.com>

Junio C Hamano <gitster@pobox.com> writes:

Show 5 quoted lines

> I was wondering if we should unconditionally stuff GIT_DIR=<the
> repository location for the submodule> in the cp.env_array passed to
> the function prepare_submodule_repo_env().  As cp.dir will be set to
> the submodule's working tree, there is no need to set GIT_WORK_TREE
> and export it, I think, although it would not hurt.

After checking all callers of prepare_submodule_repo_env() and saw that cp.dir is set to the top of working directory for the submodule, I wonder if something as simple and stupid like the attached patch is sufficient. Our subprocess will go there, and there should be a .git embedded directory or a .git file that points into .git/modules/* in the superproject, and either way, it should use .git directly underneath it.

 submodule.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/submodule.c b/submodule.c
index 1b5cdfb..e8258f0 100644
--- a/submodule.c
+++ b/submodule.c
@@ -1160,4 +1160,5 @@ void prepare_submodule_repo_env(struct argv_array *out)
 		if (strcmp(*var, CONFIG_DATA_ENVIRONMENT))
 			argv_array_push(out, *var);
 	}
+	argv_array_push(out, "GIT_DIR=.git");
 }