Subject: Re: [PATCH] fetch set_head: fix non-mirror remotes in bare repositories

From: Patrick Steinhardt <[email-masked]>
Date: Fri, 24 Jan 2025 06:56:35 +0100

On Sun, Jan 12, 2025 at 05:51:22PM +0100, Bence Ferdinandy wrote:
> diff --git a/builtin/fetch.c b/builtin/fetch.c
> index fe2b26c74a..625d45be8b 100644
> --- a/builtin/fetch.c
> +++ b/builtin/fetch.c
> @@ -1925,7 +1925,8 @@ static int do_fetch(struct transport *transport,
>  		}
>  	}
>  	if (set_head(remote_refs, transport->remote->follow_remote_head,
> -		transport->remote->no_warn_branch))
> +		transport->remote->no_warn_branch,
> +		transport->remote->mirror))
>  		;
>  		/*
>  		 * Way too many cases where this can go wrong

Nit: At this point it might be sensible to simply pass in the remote
itself, which would allow for an easier callsite and less risk of
getting the order of parameters wrong.

> diff --git a/t/t5505-remote.sh b/t/t5505-remote.sh
> index 519f7973e3..c75cfe968f 100755
> --- a/t/t5505-remote.sh
> +++ b/t/t5505-remote.sh
> @@ -589,6 +589,16 @@ test_expect_success 'add --mirror setting HEAD' '
>  	)
>  '
>  
> +test_expect_success 'non-mirror fetch does not interfere with mirror' '
> +	mkdir headnotmain &&

Nit: this can be simplified into `git init --bare -b notmain
headnotmain` so that you don't have to create an empty directory first.
Also, do we want to `test_when_finished rm -rf headnotmain` to clean up
after ourselves?

> +	(
> +		cd headnotmain &&
> +		git init --bare -b notmain &&
> +		git remote add -f other ../two &&
> +		test "$(git symbolic-ref HEAD)" = "refs/heads/notmain"
> +	)
> +'
> +
>  test_expect_success 'add --mirror=fetch' '
>  	mkdir mirror-fetch &&
>  	git init -b main mirror-fetch/parent &&
> diff --git a/t/t5510-fetch.sh b/t/t5510-fetch.sh
> index 2d9587059f..cfa63ae086 100755
> --- a/t/t5510-fetch.sh
> +++ b/t/t5510-fetch.sh
> @@ -84,6 +84,19 @@ test_expect_success "fetch test remote HEAD" '
>  	branch=$(git rev-parse refs/remotes/origin/main) &&
>  	test "z$head" = "z$branch"'
>  
> +test_expect_success "fetch test remote HEAD in bare repository" '
> +	cd "$D" &&
> +	git init --bare barerepo &&
> +	cd barerepo &&

The `cd` needs to happen in a subshell. ALso, the same comment here
regarding whether we want to have `test_when_finished` to clean up
state.

> +	git remote add upstream ../two &&
> +	git fetch upstream &&
> +	git rev-parse --verify refs/remotes/upstream/HEAD &&
> +	git rev-parse --verify refs/remotes/upstream/main &&
> +	head=$(git rev-parse refs/remotes/upstream/HEAD) &&
> +	branch=$(git rev-parse refs/remotes/upstream/main) &&
> +	test "z$head" = "z$branch"'

The closing single-quote should be on its own line.

I see though that you simply follow existing code style, both for the
call to cd(1) and for the single-quote, so these are fine. This test
file could use a makeover, but that is obviously outside of the scope of
this patch series.

Patrick