Re: [PATCH] submodule: use cheaper check for submodule pushes

From: Jonathan Nieder <jrnieder@gmail.com>
Date: Jul 13, 2017, 00:01 UTC
Message-ID: <20170713000117.GJ93855@aiede.mtv.corp.google.com>
In-Reply-To: <20170712234504.15811-1-sbeller@google.com>

Hi,

Stefan Beller wrote:

Show 14 quoted lines

> In the function push_submodule[1] we use add_submodule_odb[2] to determine
> if a submodule has been populated. However the function does not work with
> the submodules objects that are added, instead a new child process is used
> to perform the actual push in the submodule.
>
> Use is_submodule_populated[3] that is cheaper to guard from unpopulated
> submodules.
>
> [1] 'push_submodule' was added in eb21c732d6 (push: teach
>     --recurse-submodules the on-demand option, 2012-03-29)
> [2] 'add_submodule_odb' was introduced in 752c0c2492 (Add the
>     --submodule option to the diff option family, 2009-10-19)
> [3] 'is_submodule_populated' was added in 5688c28d81 (submodules:
>     add helper to determine if a submodule is populated, 2016-12-16)

These footnotes don't answer the question that I really have: why did this use add_submodule_odb in the first place?

E.g. did the ref iteration code require access to the object store previously and stop requiring it later?

Show 17 quoted lines

> Signed-off-by: Stefan Beller <sbeller@google.com>
> ---
>  submodule.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/submodule.c b/submodule.c
> index da2b484879..55afad3e8c 100644
> --- a/submodule.c
> +++ b/submodule.c
> @@ -976,7 +976,9 @@ static int push_submodule(const char *path,
>  			  const struct string_list *push_options,
>  			  int dry_run)
>  {
> -	if (add_submodule_odb(path))
> +	int code;
> +
> +	if (!is_submodule_populated_gently(path, &code))

Should this examine the code to distinguish between hard errors (e.g. "Error reading .git") and a missing repository?

Thanks, Jonathan