Re: [PATCH v2] checkpatch: use patch subject when reading from stdin

[Andrew Morton <akpm@linux-foundation.org>]

On Tue,  5 May 2020 15:26:13 +0200 Geert Uytterhoeven <geert+renesas@glider.be> wrote:

> While "git am" can apply an mbox file containing multiple patches (e.g.
> as created by b4[1], or a patch bundle downloaded from patchwork),
> checkpatch does not have proper support for that.  When operating on an
> mbox, checkpatch will merge all detected tags, and complain falsely
> about duplicates:
> 
>     WARNING: Duplicate signature
> 
> As modifying checkpatch to reset state in between each patch is a lot of
> work, a simple solution is splitting the mbox into individual patches,
> and invoking checkpatch for each of them.  Fortunately checkpatch can read
> a patch from stdin, so the classic "formail" tool can be used to split
> the mbox, and pipe all individual patches to checkpatch:
> 
>     formail -s scripts/checkpatch.pl < my-mbox
> 
> However, when reading a patch file from standard input, checkpatch calls
> it "Your patch", and reports its state as:
> 
>     Your patch has style problems, please review.
> 
> or:
> 
>     Your patch has no obvious style problems and is ready for submission.

Showing the proposed "after patch" output would be helpful.  It seems
that it will be

	"checkpatch: use patch subject when reading from stdin" has no obvious style problems and is ready for submission.

yes?

> Hence it can be difficult to identify which patches need to be reviewed
> and improved.
> 
> Fix this by replacing "Your patch" by (the first line of) the email
> subject, if present.
> 
> Note that "git mailsplit" can also be used to split an mbox, but it will
> create individual files for each patch, thus requiring cleanup
> afterwards.  Formail does not have this disadvantage.
>