Jeff King <peff@xxxxxxxx> writes: > > -- >8 -- > Subject: [PATCH] p5332: drop "+" from --stdin-packs input > > This perf script creates a midx by running "git multi-pack-index write" > with the "--stdin-packs" option. We feed that stdin by running "find" on > .git/objects/pack, using sed to strip off everything but the basename. > > But that sed invocation also does something peculiar: it adds a "+" to > the start of each pack name. This causes the multi-pack-index command to > barf. The modified name does not match any pack it knows about, so it > ends up with an empty list of packs to put in the midx. And thus nothing > matches the --preferred-pack option we pass, which causes it die(). > > The fix is to remove the extra "+" (which also lets us simplify the sed > invocation a bit, as it is now just stripping the leading directories). > > But that leaves the mystery of why it was ever there in the first place. > The answer is that an earlier iteration of the patch series had a > concept of "disjoint" packs in the midx. And one of its patches here: > > https://lore.kernel.org/git/c52d7e7b27a9add4f58b8334db4fe4498af1c90f.1701198172.git.me@xxxxxxxxxxxx/ > > taught read_packs_from_stdin() to treat a leading "+" as marking a > disjoint pack. But in the second version of the series, which was > ultimately merged, that disjoint concept went away, and the code to > parse "+" did likewise. The regular regression tests were adjusted to > match, but this case in t/perf was forgotten. > > Signed-off-by: Jeff King <peff@xxxxxxxx> > --- > t/perf/p5332-multi-pack-reuse.sh | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) Thanks. I wonder if we had some tools and mechanisms people were discussing to track changes on changsets, such a mishap could have been caught more easily. [jc: random folks from that discussion CC'ed, just in case they are interested]. > > diff --git a/t/perf/p5332-multi-pack-reuse.sh b/t/perf/p5332-multi-pack-reuse.sh > index d1c89a8b7d..0a2525db44 100755 > --- a/t/perf/p5332-multi-pack-reuse.sh > +++ b/t/perf/p5332-multi-pack-reuse.sh > @@ -58,7 +58,7 @@ do > ' > > test_expect_success "setup bitmaps for $nr_packs-pack scenario" ' > - find $packdir -type f -name "*.idx" | sed -e "s/.*\/\(.*\)$/+\1/g" | > + find $packdir -type f -name "*.idx" | sed -e "s/.*\///" | > git multi-pack-index write --stdin-packs --bitmap \ > --preferred-pack="$(find_pack $(git rev-parse HEAD))" > '
