Re: [PATCH] grep: ignore --recurse-submodules if --no-index is given

[Johannes Schindelin <Johannes.Schindelin@gmx.de>]

Hi Philippe,

On Sun, 26 Jan 2020, Philippe Blain via GitGitGadget wrote:

> From: Philippe Blain <levraiphilippeblain@gmail.com>
>
> Since grep learned to recurse into submodules in 0281e487fd
> (grep: optionally recurse into submodules, 2016-12-16),
> using --recurse-submodules along with --no-index makes Git
> die().
>
> This is unfortunate because if submodule.recurse is set in a user's
> ~/.gitconfig, invoking `git grep --no-index` either inside or outside
> a Git repository results in
>
>     fatal: option not supported with --recurse-submodules
>
> Let's allow using these options together, so that setting submodule.recurse
> globally does not prevent using `git grep --no-index`.
>
> Using `--recurse-submodules` should not have any effect if `--no-index`
> is used inside a repository, as Git will recurse into the checked out
> submodule directories just like into regular directories.
>
> Signed-off-by: Philippe Blain <levraiphilippeblain@gmail.com>

My initial reaction to this patch was: "but why would you try to combine
`--recurse-submodules` with `--no-index`?". The `submodule.recurse`
reference made me think again, though.

And then it hit me: by `--no-index`, what we _really_ mean to say is:
ignore that this _might_ be tracked in Git. And that obviously means that
there cannot be any submodules to recurse into, as far as `git diff
--no-index` is concerned.

So I think your patch makes a ton of sense.

Thanks,
Dscho

> ---
>     grep: ignore --recurse-submodules if --no-index is given
>
>     Since grep learned to recurse into submodules in 0281e487fd (grep:
>     optionally recurse into submodules, 2016-12-16), using
>     --recurse-submodules along with --no-index makes Git die().
>
>     This is unfortunate because if submodule.recurse is set in a user's
>     ~/.gitconfig, invoking git grep --no-index either inside or outside a
>     Git repository results in
>
>     fatal: option not supported with --recurse-submodules
>
>     Let's allow using these options together, so that setting
>     submodule.recurse globally does not prevent using git grep --no-index.
>
>     Using --recurse-submodules should not have any effect if --no-indexis
>     used inside a repository, as Git will recurse into the checked out
>     submodule directories just like into regular directories.
>
> Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-540%2Fphil-blain%2Fgrep-no-index-ignore-recurse-submodule-v1
> Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-540/phil-blain/grep-no-index-ignore-recurse-submodule-v1
> Pull-Request: https://github.com/gitgitgadget/git/pull/540
>
>  Documentation/git-grep.txt         |  3 ++-
>  builtin/grep.c                     |  4 ++--
>  t/t7814-grep-recurse-submodules.sh | 11 ++++++++++-
>  3 files changed, 14 insertions(+), 4 deletions(-)
>
> diff --git a/Documentation/git-grep.txt b/Documentation/git-grep.txt
> index c89fb569e3..ffc3a6efdc 100644
> --- a/Documentation/git-grep.txt
> +++ b/Documentation/git-grep.txt
> @@ -96,7 +96,8 @@ OPTIONS
>  	Recursively search in each submodule that has been initialized and
>  	checked out in the repository.  When used in combination with the
>  	<tree> option the prefix of all submodule output will be the name of
> -	the parent project's <tree> object.
> +	the parent project's <tree> object. This option has no effect
> +	if `--no-index` is given.
>
>  -a::
>  --text::
> diff --git a/builtin/grep.c b/builtin/grep.c
> index 50ce8d9461..d5f089dd41 100644
> --- a/builtin/grep.c
> +++ b/builtin/grep.c
> @@ -1115,8 +1115,8 @@ int cmd_grep(int argc, const char **argv, const char *prefix)
>  		}
>  	}
>
> -	if (recurse_submodules && (!use_index || untracked))
> -		die(_("option not supported with --recurse-submodules"));
> +	if (recurse_submodules && untracked)
> +		die(_("--untracked not supported with --recurse-submodules"));
>
>  	if (!show_in_pager && !opt.status_only)
>  		setup_pager();
> diff --git a/t/t7814-grep-recurse-submodules.sh b/t/t7814-grep-recurse-submodules.sh
> index 946f91fa57..828cb3ba58 100755
> --- a/t/t7814-grep-recurse-submodules.sh
> +++ b/t/t7814-grep-recurse-submodules.sh
> @@ -345,7 +345,16 @@ test_incompatible_with_recurse_submodules ()
>  }
>
>  test_incompatible_with_recurse_submodules --untracked
> -test_incompatible_with_recurse_submodules --no-index
> +
> +test_expect_success 'grep --recurse-submodules --no-index ignores --recurse-submodules' '
> +	git grep --recurse-submodules --no-index -e "^(.|.)[\d]" >actual &&
> +	cat >expect <<-\EOF &&
> +	a:(1|2)d(3|4)
> +	submodule/a:(1|2)d(3|4)
> +	submodule/sub/a:(1|2)d(3|4)
> +	EOF
> +	test_cmp expect actual
> +'
>
>  test_expect_success 'grep --recurse-submodules should pass the pattern type along' '
>  	# Fixed
>
> base-commit: bc7a3d4dc04dd719e7c8c35ebd7a6e6651c5c5b6
> --
> gitgitgadget
>