Re: [PATCH] git: extend --no-lazy-fetch to work across subprocesses

From: Jeff King <peff@peff.net>
Date: Feb 27, 2024, 07:49 UTC
Message-ID: <20240227074903.GD3263678@coredump.intra.peff.net>
In-Reply-To: <xmqqfrxexx15.fsf@gitster.g>

On Mon, Feb 26, 2024 at 10:04:54PM -0800, Junio C Hamano wrote:

> ----- >8 --------- >8 --------- >8 --------- >8 -----
> Subject: [PATCH v2 3/3] git: extend --no-lazy-fetch to work across subprocesses
> [...]

This looks pretty reasonable to me, and the lines you drew for #leftoverbits all seemed liked good spots.

The only thing I noticed in the patch was this (which I think is not even new in this round):

Show 12 quoted lines

> diff --git a/environment.c b/environment.c
> index 9e37bf58c0..afad78a3f8 100644
> --- a/environment.c
> +++ b/environment.c
> @@ -136,6 +136,7 @@ const char * const local_repo_env[] = {
>  	GRAFT_ENVIRONMENT,
>  	INDEX_ENVIRONMENT,
>  	NO_REPLACE_OBJECTS_ENVIRONMENT,
> +	NO_LAZY_FETCH_ENVIRONMENT,
>  	GIT_REPLACE_REF_BASE_ENVIRONMENT,
>  	GIT_PREFIX_ENVIRONMENT,
>  	GIT_SHALLOW_FILE_ENVIRONMENT,

This will clear the environment variable when we move between repositories. I can see an argument for it, and certainly that's how GIT_NO_REPLACE_OBJECTS works.

But I can also see an argument that this is not a property of the _repository_, but of the request. For example, if I run "git --no-lazy-fetch log" and we cross into a submodule to do a diff, should that submodule also avoid lazy-fetching? I'd think so, but I think your patch would restore the defaults when we "enter" the submodule repo.

There's some prior art there, I think, in how GIT_CEILING_DIRECTORIES works, or even something like "git --literal-pathspecs", neither of which appear in local_repo_env.

-Peff