From: Omar Polo <op@omarpolo.com>
Subject: Re: mg: grep buffer improvements
To: Dante Catalfamo <dante@lambda.cx>
Cc: tech@openbsd.org
Date: Tue, 04 Jun 2024 09:58:49 +0200

Hello,

On 2024/06/02 23:31:17 -0400, Dante Catalfamo <dante@lambda.cx> wrote:
> Hi,
> 
> This copies behaviour from Emacs, and makes navigating the `grep`
> buffer easier and faster.

Yeah.  This applies to the *compile* buffer too, it's very handy!  I use
it on Emacs all the time.

> The grep output buffer is marked read-only. Pressing `n` will jump to
> the next file:line and open it in a split, but will keep focus on the
> grep buffer. This lets you quickly press `n` so scan through the
> results. It does the same with `p`, but it goes to the previous result
> instead of the next.

unfortunately `p' doesn't work in a *compile* buffer since it doesn't
search backwards.  The compilers will split several lines of nonsense
between actual errors but make also shows the commands ran inbetween.

compile_goto_error() should probably learn to walk the output backward
too, but it doesn't seem a trivial routine.

some minor style nits below.


Thanks!

> +int
> +grep_next_error(int f, int n)
> +{
> +	int ret;
> +
> +	if ((ret = next_error(f, n)) != (TRUE)) {

nit: no need to wrap TRUE in parethesis, and these brances are
superfluous.  (most of the mg code doesn't use braces when there's just
one statement.)

> +		return ret;
> +	}
> +
> +	curwp = compile_win;
> +	curbp = compile_buffer;
> +
> +	return (TRUE);

this wrapping instead is just style, so please keep it.

> +}
> +
> +int
> +grep_previous_error(int f, int n)
> +{
> +	int ret;
> +
> +	if ((ret = previous_error(f, n)) != (TRUE)) {

ditto.

> +		return ret;
> +	}
> +
> +	curwp = compile_win;
> +	curbp = compile_buffer;
> +
> +	return (TRUE);
> +}