git-commit-vandalism/t/t5310-pack-bitmaps.sh
Jeff King 9df4a6074a pack-objects: disable pack reuse for object-selection options
If certain options like --honor-pack-keep, --local, or
--incremental are used with pack-objects, then we need to
feed each potential object to want_object_in_pack() to see
if it should be filtered out. But when the bitmap
reuse_packfile optimization is in effect, we do not call
that function at all, and in fact skip adding the objects to
the to_pack list entirely.  This means we have a bug: for
certain requests we will silently ignore those options and
include objects in that pack that should not be there.

The problem has been present since the inception of the
pack-reuse code in 6b8fda2db (pack-objects: use bitmaps when
packing objects, 2013-12-21), but it was unlikely to come up
in practice.  These options are generally used for on-disk
packing, not transfer packs (which go to stdout), but we've
never allowed pack reuse for non-stdout packs (until
645c432d6, we did not even use bitmaps, which the reuse
optimization relies on; after that, we explicitly turned it
off when not packing to stdout).

We can fix this by just disabling the reuse_packfile
optimization when the options are in use. In theory we could
teach the pack-reuse code to satisfy these checks, but it's
not worth the complexity. The purpose of the optimization is
to keep the amount of per-object work we do to a minimum.
But these options inherently require us to search for other
copies of each object, drowning out any benefit of the
pack-reuse optimization. But note that the optimizations
from 56dfeb626 (pack-objects: compute local/ignore_pack_keep
early, 2016-07-29) happen before pack-reuse, meaning that
specifying "--honor-pack-keep" in a repository with no .keep
files can still follow the fast path.

There are tests in t5310 that check these options with
bitmaps and --stdout, but they didn't catch the bug, and
it's hard to adapt them to do so.

One problem is that they don't use --delta-base-offset;
without that option, we always disable the reuse
optimization entirely. It would be fine to add it in (it
actually makes the test more realistic), but that still
isn't quite enough.

The other problem is that the reuse code is very picky; it
only kicks in when it can reuse most of a pack, starting
from the first byte. So we'd have to start from a fully
repacked and bitmapped state to trigger it. But the tests
for these options use a much more subtle state; they want to
be sure that the want_object_in_pack() code is allowing some
objects but not others. Doing a full repack runs counter to
that.

So this patch adds new tests at the end of the script which
create the fully-packed state and make sure that each option
is not fooled by reusable pack.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-05-09 12:07:24 +09:00

331 lines
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#!/bin/sh
test_description='exercise basic bitmap functionality'
. ./test-lib.sh
objpath () {
echo ".git/objects/$(echo "$1" | sed -e 's|\(..\)|\1/|')"
}
# show objects present in pack ($1 should be associated *.idx)
list_packed_objects () {
git show-index <"$1" | cut -d' ' -f2
}
# has_any pattern-file content-file
# tests whether content-file has any entry from pattern-file with entries being
# whole lines.
has_any () {
grep -Ff "$1" "$2"
}
test_expect_success 'setup repo with moderate-sized history' '
for i in $(test_seq 1 10); do
test_commit $i
done &&
git checkout -b other HEAD~5 &&
for i in $(test_seq 1 10); do
test_commit side-$i
done &&
git checkout master &&
bitmaptip=$(git rev-parse master) &&
blob=$(echo tagged-blob | git hash-object -w --stdin) &&
git tag tagged-blob $blob &&
git config repack.writebitmaps true &&
git config pack.writebitmaphashcache true
'
test_expect_success 'full repack creates bitmaps' '
git repack -ad &&
ls .git/objects/pack/ | grep bitmap >output &&
test_line_count = 1 output
'
test_expect_success 'rev-list --test-bitmap verifies bitmaps' '
git rev-list --test-bitmap HEAD
'
rev_list_tests() {
state=$1
test_expect_success "counting commits via bitmap ($state)" '
git rev-list --count HEAD >expect &&
git rev-list --use-bitmap-index --count HEAD >actual &&
test_cmp expect actual
'
test_expect_success "counting partial commits via bitmap ($state)" '
git rev-list --count HEAD~5..HEAD >expect &&
git rev-list --use-bitmap-index --count HEAD~5..HEAD >actual &&
test_cmp expect actual
'
test_expect_success "counting commits with limit ($state)" '
git rev-list --count -n 1 HEAD >expect &&
git rev-list --use-bitmap-index --count -n 1 HEAD >actual &&
test_cmp expect actual
'
test_expect_success "counting non-linear history ($state)" '
git rev-list --count other...master >expect &&
git rev-list --use-bitmap-index --count other...master >actual &&
test_cmp expect actual
'
test_expect_success "counting commits with limiting ($state)" '
git rev-list --count HEAD -- 1.t >expect &&
git rev-list --use-bitmap-index --count HEAD -- 1.t >actual &&
test_cmp expect actual
'
test_expect_success "enumerate --objects ($state)" '
git rev-list --objects --use-bitmap-index HEAD >tmp &&
cut -d" " -f1 <tmp >tmp2 &&
sort <tmp2 >actual &&
git rev-list --objects HEAD >tmp &&
cut -d" " -f1 <tmp >tmp2 &&
sort <tmp2 >expect &&
test_cmp expect actual
'
test_expect_success "bitmap --objects handles non-commit objects ($state)" '
git rev-list --objects --use-bitmap-index HEAD tagged-blob >actual &&
grep $blob actual
'
}
rev_list_tests 'full bitmap'
test_expect_success 'clone from bitmapped repository' '
git clone --no-local --bare . clone.git &&
git rev-parse HEAD >expect &&
git --git-dir=clone.git rev-parse HEAD >actual &&
test_cmp expect actual
'
test_expect_success 'setup further non-bitmapped commits' '
for i in $(test_seq 1 10); do
test_commit further-$i
done
'
rev_list_tests 'partial bitmap'
test_expect_success 'fetch (partial bitmap)' '
git --git-dir=clone.git fetch origin master:master &&
git rev-parse HEAD >expect &&
git --git-dir=clone.git rev-parse HEAD >actual &&
test_cmp expect actual
'
test_expect_success 'incremental repack fails when bitmaps are requested' '
test_commit more-1 &&
test_must_fail git repack -d 2>err &&
test_i18ngrep "Incremental repacks are incompatible with bitmap" err
'
test_expect_success 'incremental repack can disable bitmaps' '
test_commit more-2 &&
git repack -d --no-write-bitmap-index
'
test_expect_success 'pack-objects respects --local (non-local loose)' '
git init --bare alt.git &&
echo $(pwd)/alt.git/objects >.git/objects/info/alternates &&
echo content1 >file1 &&
# non-local loose object which is not present in bitmapped pack
altblob=$(GIT_DIR=alt.git git hash-object -w file1) &&
# non-local loose object which is also present in bitmapped pack
git cat-file blob $blob | GIT_DIR=alt.git git hash-object -w --stdin &&
git add file1 &&
test_tick &&
git commit -m commit_file1 &&
echo HEAD | git pack-objects --local --stdout --revs >1.pack &&
git index-pack 1.pack &&
list_packed_objects 1.idx >1.objects &&
printf "%s\n" "$altblob" "$blob" >nonlocal-loose &&
! has_any nonlocal-loose 1.objects
'
test_expect_success 'pack-objects respects --honor-pack-keep (local non-bitmapped pack)' '
echo content2 >file2 &&
blob2=$(git hash-object -w file2) &&
git add file2 &&
test_tick &&
git commit -m commit_file2 &&
printf "%s\n" "$blob2" "$bitmaptip" >keepobjects &&
pack2=$(git pack-objects pack2 <keepobjects) &&
mv pack2-$pack2.* .git/objects/pack/ &&
>.git/objects/pack/pack2-$pack2.keep &&
rm $(objpath $blob2) &&
echo HEAD | git pack-objects --honor-pack-keep --stdout --revs >2a.pack &&
git index-pack 2a.pack &&
list_packed_objects 2a.idx >2a.objects &&
! has_any keepobjects 2a.objects
'
test_expect_success 'pack-objects respects --local (non-local pack)' '
mv .git/objects/pack/pack2-$pack2.* alt.git/objects/pack/ &&
echo HEAD | git pack-objects --local --stdout --revs >2b.pack &&
git index-pack 2b.pack &&
list_packed_objects 2b.idx >2b.objects &&
! has_any keepobjects 2b.objects
'
test_expect_success 'pack-objects respects --honor-pack-keep (local bitmapped pack)' '
ls .git/objects/pack/ | grep bitmap >output &&
test_line_count = 1 output &&
packbitmap=$(basename $(cat output) .bitmap) &&
list_packed_objects .git/objects/pack/$packbitmap.idx >packbitmap.objects &&
test_when_finished "rm -f .git/objects/pack/$packbitmap.keep" &&
>.git/objects/pack/$packbitmap.keep &&
echo HEAD | git pack-objects --honor-pack-keep --stdout --revs >3a.pack &&
git index-pack 3a.pack &&
list_packed_objects 3a.idx >3a.objects &&
! has_any packbitmap.objects 3a.objects
'
test_expect_success 'pack-objects respects --local (non-local bitmapped pack)' '
mv .git/objects/pack/$packbitmap.* alt.git/objects/pack/ &&
test_when_finished "mv alt.git/objects/pack/$packbitmap.* .git/objects/pack/" &&
echo HEAD | git pack-objects --local --stdout --revs >3b.pack &&
git index-pack 3b.pack &&
list_packed_objects 3b.idx >3b.objects &&
! has_any packbitmap.objects 3b.objects
'
test_expect_success 'pack-objects to file can use bitmap' '
# make sure we still have 1 bitmap index from previous tests
ls .git/objects/pack/ | grep bitmap >output &&
test_line_count = 1 output &&
# verify equivalent packs are generated with/without using bitmap index
packasha1=$(git pack-objects --no-use-bitmap-index --all packa </dev/null) &&
packbsha1=$(git pack-objects --use-bitmap-index --all packb </dev/null) &&
list_packed_objects <packa-$packasha1.idx >packa.objects &&
list_packed_objects <packb-$packbsha1.idx >packb.objects &&
test_cmp packa.objects packb.objects
'
test_expect_success 'full repack, reusing previous bitmaps' '
git repack -ad &&
ls .git/objects/pack/ | grep bitmap >output &&
test_line_count = 1 output
'
test_expect_success 'fetch (full bitmap)' '
git --git-dir=clone.git fetch origin master:master &&
git rev-parse HEAD >expect &&
git --git-dir=clone.git rev-parse HEAD >actual &&
test_cmp expect actual
'
test_expect_success 'create objects for missing-HAVE tests' '
blob=$(echo "missing have" | git hash-object -w --stdin) &&
tree=$(printf "100644 blob $blob\tfile\n" | git mktree) &&
parent=$(echo parent | git commit-tree $tree) &&
commit=$(echo commit | git commit-tree $tree -p $parent) &&
cat >revs <<-EOF
HEAD
^HEAD^
^$commit
EOF
'
test_expect_success 'pack-objects respects --incremental' '
cat >revs2 <<-EOF &&
HEAD
$commit
EOF
git pack-objects --incremental --stdout --revs <revs2 >4.pack &&
git index-pack 4.pack &&
list_packed_objects 4.idx >4.objects &&
test_line_count = 4 4.objects &&
git rev-list --objects $commit >revlist &&
cut -d" " -f1 revlist |sort >objects &&
test_cmp 4.objects objects
'
test_expect_success 'pack with missing blob' '
rm $(objpath $blob) &&
git pack-objects --stdout --revs <revs >/dev/null
'
test_expect_success 'pack with missing tree' '
rm $(objpath $tree) &&
git pack-objects --stdout --revs <revs >/dev/null
'
test_expect_success 'pack with missing parent' '
rm $(objpath $parent) &&
git pack-objects --stdout --revs <revs >/dev/null
'
test_expect_success JGIT 'we can read jgit bitmaps' '
git clone . compat-jgit &&
(
cd compat-jgit &&
rm -f .git/objects/pack/*.bitmap &&
jgit gc &&
git rev-list --test-bitmap HEAD
)
'
test_expect_success JGIT 'jgit can read our bitmaps' '
git clone . compat-us &&
(
cd compat-us &&
git repack -adb &&
# jgit gc will barf if it does not like our bitmaps
jgit gc
)
'
test_expect_success 'splitting packs does not generate bogus bitmaps' '
test-genrandom foo $((1024 * 1024)) >rand &&
git add rand &&
git commit -m "commit with big file" &&
git -c pack.packSizeLimit=500k repack -adb &&
git init --bare no-bitmaps.git &&
git -C no-bitmaps.git fetch .. HEAD
'
test_expect_success 'set up reusable pack' '
rm -f .git/objects/pack/*.keep &&
git repack -adb &&
reusable_pack () {
git for-each-ref --format="%(objectname)" |
git pack-objects --delta-base-offset --revs --stdout "$@"
}
'
test_expect_success 'pack reuse respects --honor-pack-keep' '
test_when_finished "rm -f .git/objects/pack/*.keep" &&
for i in .git/objects/pack/*.pack; do
>${i%.pack}.keep
done &&
reusable_pack --honor-pack-keep >empty.pack &&
git index-pack empty.pack &&
>expect &&
git show-index <empty.idx >actual &&
test_cmp expect actual
'
test_expect_success 'pack reuse respects --local' '
mv .git/objects/pack/* alt.git/objects/pack/ &&
test_when_finished "mv alt.git/objects/pack/* .git/objects/pack/" &&
reusable_pack --local >empty.pack &&
git index-pack empty.pack &&
>expect &&
git show-index <empty.idx >actual &&
test_cmp expect actual
'
test_expect_success 'pack reuse respects --incremental' '
reusable_pack --incremental >empty.pack &&
git index-pack empty.pack &&
>expect &&
git show-index <empty.idx >actual &&
test_cmp expect actual
'
test_done