Subject: Re: [PATCH] completion: use awk for filtering the config entries

From: Junio C Hamano <[email-masked]>
Date: Fri, 16 Feb 2024 09:35:31 -0800

Beat Bolli <[email-masked]> writes:

> Commits 1e0ee4087e (completion: add and use
> __git_compute_first_level_config_vars_for_section, 2024-02-10) and
> 6e32f718ff (completion: add and use
> __git_compute_second_level_config_vars_for_section, 2024-02-10)
> introduced new helpers for config completion.
>
> Both helpers use a pipeline of grep and awk to filter the list of config
> entries. awk is perfectly capable of filtering, so let's eliminate the
> grep process and move the filtering into the awk script.

Makes sense.  I wonder if we can have some simple script sanity
checker that catches things like this, e.g., catting a single file
into pipe, grep appearing upstream of awk or sed, etc.

> The "-E" grep option (extended syntax) was not necessary, as $section is
> a single word.
>
> While at it, wrap the over-long lines to make them more readable.
>
> Signed-off-by: Beat Bolli <[email-masked]>
> ---
>
> Junio, this goes on top of 'pb/complete-config' which is on next
> currently.

Alternatively we could redo the topic, squashing this fix in, after
the release when we rewind 'next'.

Thanks.

>
>  contrib/completion/git-completion.bash | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/contrib/completion/git-completion.bash b/contrib/completion/git-completion.bash
> index 444b3efa63..fcf1afd75d 100644
> --- a/contrib/completion/git-completion.bash
> +++ b/contrib/completion/git-completion.bash
> @@ -2673,7 +2673,8 @@ __git_compute_first_level_config_vars_for_section ()
>  	__git_compute_config_vars
>  	local this_section="__git_first_level_config_vars_for_section_${section}"
>  	test -n "${!this_section}" ||
> -	printf -v "__git_first_level_config_vars_for_section_${section}" %s "$(echo "$__git_config_vars" | grep -E "^${section}\.[a-z]" | awk -F. '{print $2}')"
> +	printf -v "__git_first_level_config_vars_for_section_${section}" %s \
> +		"$(echo "$__git_config_vars" | awk -F. "/^${section}\.[a-z]/ { print \$2 }")"
>  }
>  
>  __git_compute_second_level_config_vars_for_section ()
> @@ -2682,7 +2683,8 @@ __git_compute_second_level_config_vars_for_section ()
>  	__git_compute_config_vars_all
>  	local this_section="__git_second_level_config_vars_for_section_${section}"
>  	test -n "${!this_section}" ||
> -	printf -v "__git_second_level_config_vars_for_section_${section}" %s "$(echo "$__git_config_vars_all" | grep -E "^${section}\.<" | awk -F. '{print $3}')"
> +	printf -v "__git_second_level_config_vars_for_section_${section}" %s \
> +		"$(echo "$__git_config_vars_all" | awk -F. "/^${section}\.</ { print \$3 }")"
>  }
>  
>  __git_config_sections=