From: Johannes Sixt <j6t@kdbg.org>
Date: Fri, 30 Oct 2009 20:51:18 GMT
Subject: Re: [PATCH 3/8] Teach git var about GIT_EDITOR
Message-ID: <4AEB51C6.7060204@kdbg.org>
In-Reply-To: <20091030102658.GD1610@progeny.tock>

Jonathan Nieder schrieb:
> From: Johannes Sixt <j.sixt@viscovery.net>
> 
> Expose the command used by launch_editor() for scripts to use.
> This should allow one to avoid searching for a proper editor
> separately in each command.
> 
> Signed-off-by: Johannes Sixt <j6t@kdbg.org>
> Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>

Thanks for cleaning up behind me. I don't mind if you take authorship, but 
if you do keep my name, please make it:

From: Johannes Sixt <j6t@kdbg.org>

> -int launch_editor(const char *path, struct strbuf *buffer, const char *const *env)
> +const char *git_editor(void)
>  {
>  	const char *editor, *terminal;
>  
> ... 
>  	terminal = getenv("TERM");
> -	if (!editor && (!terminal || !strcmp(terminal, "dumb")))
> +	if (!editor && (!terminal || !strcmp(terminal, "dumb"))) {
>  		/* Terminal is dumb but no VISUAL nor EDITOR defined. */
> -		return error(
> +		error(
>  		  "No editor specified in GIT_EDITOR, core.editor, VISUAL,\n"
>  		  "or EDITOR. Tried to fall back to vi but terminal is dumb.\n"
>  		  "Please set one of these variables to an appropriate\n"
>  		  "editor or run again with options that will not cause an\n"
>  		  "editor to be invoked (e.g., -m or -F for git commit).");
> +		return NULL;
> +	}

I somehow dislike that this huge error message is in git_editor(). The 
return value, NULL, should be indication enough for the callers to handle 
the situation suitable. In particular, launch_editor() wants to write this 
big warning, but 'git var -l' can avoid the error message and write only a 
short notice:

GIT_EDITOR=terminal is dumb, but VISUAL and EDITOR unset

> +static const char *editor(int flag)
> +{
> +	const char *pgm = git_editor();
> +
> +	if (!pgm && (flag & IDENT_ERROR_ON_NO_NAME))
> +		die("cannot find a suitable editor");
> +	return pgm;

This should be

	return pgm ? pgm : "terminal is dumb, but VISUAL and EDITOR unset";

otherwise, 'git var -l' later trips over printf("%s", NULL).

-- Hannes