Subject: Re: [PATCH] prompt: fix missing file errors in zsh

From: Junio C Hamano <[email-masked]>
Date: Mon, 14 Apr 2014 13:30:33 -0700

Felipe Contreras <[email-masked]> writes:

> zsh seems to have a bug while redirecting the stderr of the 'read'
> command:
>
>  % read foo 2> /dev/null < foo
>  zsh: no such file or directory: foo
>
> Which causes errors to be displayed when certain files are missing.
> Let's add a convenience function to manually check if the file is
> readable before calling "read".

OK.  I wondered if this can become conditional to zsh (with the
common code still using eread, just the implementation of shell
function being different from zsh and bash), but I doubt it would be
worth it (other people can contradict me, of course).

Will queue.  Thanks.

> Signed-off-by: Felipe Contreras <[email-masked]>
> ---
>  contrib/completion/git-prompt.sh | 21 ++++++++++++++-------
>  1 file changed, 14 insertions(+), 7 deletions(-)
>
> diff --git a/contrib/completion/git-prompt.sh b/contrib/completion/git-prompt.sh
> index 7b732d2..1526086 100644
> --- a/contrib/completion/git-prompt.sh
> +++ b/contrib/completion/git-prompt.sh
> @@ -259,6 +259,13 @@ __git_ps1_colorize_gitstring ()
>  	r="$c_clear$r"
>  }
>  
> +eread ()
> +{
> +	f="$1"
> +	shift
> +	test -r "$f" && read "$@" < "$f"
> +}
> +
>  # __git_ps1 accepts 0 or 1 arguments (i.e., format string)
>  # when called from PS1 using command substitution
>  # in this mode it prints text to add to bash PS1 prompt (includes branch name)
> @@ -321,9 +328,9 @@ __git_ps1 ()
>  	local step=""
>  	local total=""
>  	if [ -d "$g/rebase-merge" ]; then
> -		read b 2>/dev/null <"$g/rebase-merge/head-name"
> -		read step 2>/dev/null <"$g/rebase-merge/msgnum"
> -		read total 2>/dev/null <"$g/rebase-merge/end"
> +		eread "$g/rebase-merge/head-name" b
> +		eread "$g/rebase-merge/msgnum" step
> +		eread "$g/rebase-merge/end" total
>  		if [ -f "$g/rebase-merge/interactive" ]; then
>  			r="|REBASE-i"
>  		else
> @@ -331,10 +338,10 @@ __git_ps1 ()
>  		fi
>  	else
>  		if [ -d "$g/rebase-apply" ]; then
> -			read step 2>/dev/null <"$g/rebase-apply/next"
> -			read total 2>/dev/null <"$g/rebase-apply/last"
> +			eread "$g/rebase-apply/next" step
> +			eread "$g/rebase-apply/last" total
>  			if [ -f "$g/rebase-apply/rebasing" ]; then
> -				read b 2>/dev/null <"$g/rebase-apply/head-name"
> +				eread "$g/rebase-apply/head-name" b
>  				r="|REBASE"
>  			elif [ -f "$g/rebase-apply/applying" ]; then
>  				r="|AM"
> @@ -358,7 +365,7 @@ __git_ps1 ()
>  			b="$(git symbolic-ref HEAD 2>/dev/null)"
>  		else
>  			local head=""
> -			if ! read head 2>/dev/null <"$g/HEAD"; then
> +			if ! eread "$g/HEAD" head; then
>  				if [ $pcmode = yes ]; then
>  					PS1="$ps1pc_start$ps1pc_end"
>  				fi