From mboxrd@z Thu Jan  1 00:00:00 1970
From: SZEDER =?iso-8859-1?Q?G=E1bor?= <szeder@ira.uka.de>
Subject: Re: [PATCH 3/3] completion: improve shell expansion of items
Date: Thu, 27 Sep 2012 02:37:51 +0200
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Cc: Felipe Contreras <felipe.contreras@gmail.com>, git@vger.kernel.org,
	Junio C Hamano <gitster@pobox.com>
To: Jeff King <peff@peff.net>
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Hi,

On Wed, Sep 26, 2012 at 05:51:19PM -0400, Jeff King wrote:
> diff --git a/contrib/completion/git-completion.bash b/contrib/completion/git-completion.bash
> index be800e0..b0416ea 100644
> --- a/contrib/completion/git-completion.bash
> +++ b/contrib/completion/git-completion.bash
> @@ -225,6 +225,18 @@ fi
>  fi
>  fi
>  
> +# Quotes each element of an IFS-delimited list for shell reuse
> +__git_quote()
> +{
> +	local i
> +	local delim
> +	for i in $1; do
> +		local quoted=${i//\'/\'\\\'\'}
> +		printf "${delim:+$IFS}'%s'" "$quoted"
> +		delim=t
> +	done
> +}
> +
>  # Generates completion reply with compgen, appending a space to possible
>  # completion words, if necessary.
>  # It accepts 1 to 4 arguments:
> @@ -261,7 +273,7 @@ __gitcomp_nl ()
>  __gitcomp_nl ()
>  {
>  	local IFS=$'\n'
> -	COMPREPLY=($(compgen -P "${2-}" -S "${4- }" -W "$1" -- "${3-$cur}"))
> +	COMPREPLY=($(compgen -P "${2-}" -S "${4- }" -W "$(__git_quote "$1")" -- "${3-$cur}"))

Iterating through all possible completion words undermines the main
reason for __gitcomp_nl()'s existence: to handle potentially large
number of possible completion words faster than the old __gitcomp().
If we really have to iterate in a subshell, then it would perhaps be
better to drop __gitcomp_nl(), go back to using __gitcomp(), and
modify that instead.

After all, anyone could drop a file called git-cmd-${meta} on his
$PATH, and then get cmd- offered, because completion of git commands
still goes through __gitcomp().