Re: [PATCH] run-command: document use_shell option

From: Jeff King <peff@peff.net>
Date: Jan 23, 2021, 00:04 UTC
Message-ID: <YAtoJ1ooPn9sdoGL@coredump.intra.peff.net>
In-Reply-To: <xmqqzh1062as.fsf@gitster.c.googlers.com>

On Fri, Jan 22, 2021 at 02:21:15PM -0800, Junio C Hamano wrote:

Show 15 quoted lines

> > -	unsigned stdout_to_stderr:1;
> > +	/**
> > +	 * Run the command from argv[0] using a shell (but note that we may
> > +	 * still optimize out the shell call if the command contains no
> > +	 * metacharacters). Note that further arguments to the command in
> > +	 * argv[1], etc, do not need to be shell-quoted.
> > +	 */
> >  	unsigned use_shell:1;
> > +
> > +	unsigned stdout_to_stderr:1;
> 
> Reads well.  Thanks.
> 
> It is curious why "diff" chose to move stdout_to_stderr line around,
> though.

Heh, I also noticed that and tried a few options to no avail (both patience/histogram, but also diff.indentHeuristic). It is one deletion and 8 insertions even if it is done the other way:

  + /*
  + ... 6 more lines ...
  + */
  + unsigned use_shell:1;
  +
    unsigned stdout_to_stderr:1;
  - unsigned use_shell:1;

so it may just come down to the order of xdiff parsing the lines.

-Peff