Re: [PATCH 0/4] grep: add more information to hunk separators

From: Junio C Hamano <gitster@pobox.com>
Date: Mar 26, 2012, 18:01 UTC
Message-ID: <7vobrjp7gu.fsf@alter.siamese.dyndns.org>
In-Reply-To: <4F709664.1060206@lsrfire.ath.cx>

René Scharfe <rene.scharfe@lsrfire.ath.cx> writes:

Show 17 quoted lines

> Looking at the above, I thought: We have unified diffs between two
> files, we have combined diffs between more than two, what about
> showing grep results as one-sided unified diffs?  ("What's the sound
> of one hand clapping?" :-)
>
> 	--- a/git.c
> 	@ -570,3 @ int main(int argc, const char **argv)
> 	-		printf("usage: %s\n\n", git_usage_string);
> 	:		list_common_cmds_help();
> 	-		printf("\n%s\n", git_more_info_string);
>
> Pro: Generalization of an established format for showing interesting
> parts of a file.  Less duplication of meta-information.  Markers that
> tell us the kind of the shown lines are kept ("-" for context, ":" for
> matches).  Machine parsable.
>
> Con: Why the "a/" prefix?  One-sided diffs, srsly?

Cute, and I tend to agree that this is probably easier to read if you are used to reading unified diffs.

Wouldn't it make more sense to replace your '-/:' with ' /=', so that at least ' ' SP retains the meaning of "this is shown merely to give you context, it is not a proper part of what you are looking for"?

The reasoning behind '=' is that it is not either -/+ as we are not really comparing anything with anything. It may also make sense to replace the per-file header line with "=== git.c" to be consistent. I haven't formed an opinion on the prefix yet; there might be a good reason to keep the depth of the path each file appear in this "grep --unidiff-like" output and "diff --patch" output, in which case "=== a/git.c" or "=== ./git.c" might be give us more uniformity.