Re: [PATCH] connect: also update offset for features without values

[Jeff King <peff@peff.net>]

On Thu, Sep 23, 2021 at 02:20:28PM -0700, Junio C Hamano wrote:

> > +test_expect_success 'bogus symref in v0 capabilities' '
> > +	test_commit foo &&
> > +	oid=$(git rev-parse HEAD) &&
> > +	{
> > +		printf "%s HEAD\0symref object-format=%s\n" "$oid" "$GIT_DEFAULT_HASH" |
> > +			test-tool pkt-line pack-raw-stdin &&
> > +		printf "0000"
> > +	} >input &&
> > +	git ls-remote --upload-pack="cat input ;:" . >actual &&
> > +	printf "%s\tHEAD\n" "$oid" >expect &&
> > +	test_cmp expect actual
> > +'
> > +
> >  test_done
> >
> > base-commit: 186eaaae567db501179c0af0bf89b34cbea02c26
> 
> I've been seeing an occasional and not-reliably-reproducible test
> failure from t5704 in 'seen' these days---since this is the only
> commit that touches t5704, I am suspecting if there is something
> racy about it, but I am coming up empty after staring at it for a
> few minutes.
> 
> Building 87446480 (connect: also update offset for features without
> values, 2021-09-18), which is an application of the patch directly on
> top of v2.33.0, and doing
> 
>     $ cd t
>     $ while sh t5704-*.sh; do :; done
> 
> I can get it fail in a dozen iterations or so when the box is
> loaded, so it does seem timing dependent.

I think the problem is that our fake upload-pack exits immediately, so
ls-remote gets SIGPIPE. In a v0 conversation, ls-remote expects to say
"0000" to indicate that it's not interested in fetching anything (in v2,
it doesn't bother, since fetching would be a separate request that it
just declines to make).

This seems to fix it:

diff --git a/t/t5704-protocol-violations.sh b/t/t5704-protocol-violations.sh
index 34538cebf0..0983c2b507 100755
--- a/t/t5704-protocol-violations.sh
+++ b/t/t5704-protocol-violations.sh
@@ -40,7 +40,7 @@ test_expect_success 'bogus symref in v0 capabilities' '
 			test-tool pkt-line pack-raw-stdin &&
 		printf "0000"
 	} >input &&
-	git ls-remote --upload-pack="cat input ;:" . >actual &&
+	git ls-remote --upload-pack="cat input; read junk;:" . >actual &&
 	printf "%s\tHEAD\n" "$oid" >expect &&
 	test_cmp expect actual
 '

-Peff