Re: [PATCH] submodule update: run at most one fetch job unless otherwise set

[Junio C Hamano <gitster@pobox.com>]

Stefan Beller <sbeller@google.com> writes:

> From: Junio C Hamano <gitster@pobox.com>
>
> In a028a1930c (fetching submodules: respect `submodule.fetchJobs`
> config option, 2016-02-29), we made sure to keep the default behavior
> of a fetching at most one submodule at once when not setting the
> newly introduced `submodule.fetchJobs` config.
>
> This regressed in 90efe595c5 (builtin/submodule--helper: factor
> out submodule updating, 2018-08-03). Fix it.
>
> Reported-by: Sjon Hortensius <sjon@parse.nl>
> Signed-off-by: Junio C Hamano <gitster@pobox.com>
> Signed-off-by: Stefan Beller <sbeller@google.com>
> ---

Thanks for tying the loose ends.

We may want to convert the _INIT macro to use the designated
initializers; I had to count the fields twice to make sure I was
tweaking the right one.  

It did not help that I saw, before looking at the current code, that
90efe595c5 added one field at the end to the struct but did not
touch _INIT macro at all.  That made me guess that max_jobs=0 was
due to _missing_ initialization value, leading me to an incorrect
fix to append an extra 1 at the end, but that was bogus.  The
missing initialization left by 90efe595 ("builtin/submodule--helper:
factor out submodule updating", 2018-08-03) was silently fixed by
f1d15713 ("builtin/submodule--helper: store update_clone information
in a struct", 2018-08-03), I think, so replacing the 0 at the end is
1 happens to be the right fix, but with designated initializers, all
these confusions are more easily avoided.


>  builtin/submodule--helper.c | 2 +-
>  t/t5526-fetch-submodules.sh | 2 ++
>  2 files changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
> index d38113a31a..1f8a4a9d52 100644
> --- a/builtin/submodule--helper.c
> +++ b/builtin/submodule--helper.c
> @@ -1551,7 +1551,7 @@ struct submodule_update_clone {
>  #define SUBMODULE_UPDATE_CLONE_INIT {0, MODULE_LIST_INIT, 0, \
>  	SUBMODULE_UPDATE_STRATEGY_INIT, 0, 0, -1, STRING_LIST_INIT_DUP, 0, \
>  	NULL, NULL, NULL, \
> -	NULL, 0, 0, 0, NULL, 0, 0, 0}
> +	NULL, 0, 0, 0, NULL, 0, 0, 1}
>  
>  
>  static void next_submodule_warn_missing(struct submodule_update_clone *suc,
> diff --git a/t/t5526-fetch-submodules.sh b/t/t5526-fetch-submodules.sh
> index 6c2f9b2ba2..a0317556c6 100755
> --- a/t/t5526-fetch-submodules.sh
> +++ b/t/t5526-fetch-submodules.sh
> @@ -524,6 +524,8 @@ test_expect_success 'fetching submodules respects parallel settings' '
>  	git config fetch.recurseSubmodules true &&
>  	(
>  		cd downstream &&
> +		GIT_TRACE=$(pwd)/trace.out git fetch &&
> +		grep "1 tasks" trace.out &&
>  		GIT_TRACE=$(pwd)/trace.out git fetch --jobs 7 &&
>  		grep "7 tasks" trace.out &&
>  		git config submodule.fetchJobs 8 &&