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git/t/t5319-multi-pack-index.sh
Derrick Stolee 3ce4ca0a56 multi-pack-index: respect repack.packKeptObjects=false 
When selecting a batch of pack-files to repack in the "git
multi-pack-index repack" command, Git should respect the
repack.packKeptObjects config option. When false, this option says that
the pack-files with an associated ".keep" file should not be repacked.
This config value is "false" by default.

There are two cases for selecting a batch of objects. The first is the
case where the input batch-size is zero, which specifies "repack
everything". The second is with a non-zero batch size, which selects
pack-files using a greedy selection criteria. Both of these cases are
updated and tested.

Reported-by: Son Luong Ngoc <sluongng@gmail.com>
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-05-10 09:50:55 -07:00

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#!/bin/sh
test_description='multi-pack-indexes'
. ./test-lib.sh
objdir=.git/objects
midx_read_expect () {
NUM_PACKS=$1
NUM_OBJECTS=$2
NUM_CHUNKS=$3
OBJECT_DIR=$4
EXTRA_CHUNKS="$5"
{
cat <<-EOF &&
header: 4d494458 1 $NUM_CHUNKS $NUM_PACKS
chunks: pack-names oid-fanout oid-lookup object-offsets$EXTRA_CHUNKS
num_objects: $NUM_OBJECTS
packs:
EOF
if test $NUM_PACKS -ge 1
then
ls $OBJECT_DIR/pack/ | grep idx | sort
fi &&
printf "object-dir: $OBJECT_DIR\n"
} >expect &&
test-tool read-midx $OBJECT_DIR >actual &&
test_cmp expect actual
}
test_expect_success 'setup' '
test_oid_init &&
test_oid_cache <<-EOF
idxoff sha1:2999
idxoff sha256:3739
packnameoff sha1:652
packnameoff sha256:940
fanoutoff sha1:1
fanoutoff sha256:3
EOF
'
test_expect_success "don't write midx with no packs" '
test_must_fail git multi-pack-index --object-dir=. write &&
test_path_is_missing pack/multi-pack-index
'
test_expect_success "Warn if a midx contains no oid" '
cp "$TEST_DIRECTORY"/t5319/no-objects.midx $objdir/pack/multi-pack-index &&
test_must_fail git multi-pack-index verify &&
rm $objdir/pack/multi-pack-index
'
generate_objects () {
i=$1
iii=$(printf '%03i' $i)
{
test-tool genrandom "bar" 200 &&
test-tool genrandom "baz $iii" 50
} >wide_delta_$iii &&
{
test-tool genrandom "foo"$i 100 &&
test-tool genrandom "foo"$(( $i + 1 )) 100 &&
test-tool genrandom "foo"$(( $i + 2 )) 100
} >deep_delta_$iii &&
{
echo $iii &&
test-tool genrandom "$iii" 8192
} >file_$iii &&
git update-index --add file_$iii deep_delta_$iii wide_delta_$iii
}
commit_and_list_objects () {
{
echo 101 &&
test-tool genrandom 100 8192;
} >file_101 &&
git update-index --add file_101 &&
tree=$(git write-tree) &&
commit=$(git commit-tree $tree -p HEAD</dev/null) &&
{
echo $tree &&
git ls-tree $tree | sed -e "s/.* \\([0-9a-f]*\\) .*/\\1/"
} >obj-list &&
git reset --hard $commit
}
test_expect_success 'create objects' '
test_commit initial &&
for i in $(test_seq 1 5)
do
generate_objects $i
done &&
commit_and_list_objects
'
test_expect_success 'write midx with one v1 pack' '
pack=$(git pack-objects --index-version=1 $objdir/pack/test <obj-list) &&
test_when_finished rm $objdir/pack/test-$pack.pack \
$objdir/pack/test-$pack.idx $objdir/pack/multi-pack-index &&
git multi-pack-index --object-dir=$objdir write &&
midx_read_expect 1 18 4 $objdir
'
midx_git_two_modes () {
git -c core.multiPackIndex=false $1 >expect &&
git -c core.multiPackIndex=true $1 >actual &&
if [ "$2" = "sorted" ]
then
sort <expect >expect.sorted &&
mv expect.sorted expect &&
sort <actual >actual.sorted &&
mv actual.sorted actual
fi &&
test_cmp expect actual
}
compare_results_with_midx () {
MSG=$1
test_expect_success "check normal git operations: $MSG" '
midx_git_two_modes "rev-list --objects --all" &&
midx_git_two_modes "log --raw" &&
midx_git_two_modes "count-objects --verbose" &&
midx_git_two_modes "cat-file --batch-all-objects --batch-check" &&
midx_git_two_modes "cat-file --batch-all-objects --batch-check --unordered" sorted
'
}
test_expect_success 'write midx with one v2 pack' '
git pack-objects --index-version=2,0x40 $objdir/pack/test <obj-list &&
git multi-pack-index --object-dir=$objdir write &&
midx_read_expect 1 18 4 $objdir
'
compare_results_with_midx "one v2 pack"
test_expect_success 'corrupt idx not opened' '
idx=$(test-tool read-midx $objdir | grep "\.idx\$") &&
mv $objdir/pack/$idx backup-$idx &&
test_when_finished "mv backup-\$idx \$objdir/pack/\$idx" &&
# This is the minimum size for a sha-1 based .idx; this lets
# us pass perfunctory tests, but anything that actually opens and reads
# the idx file will complain.
test_copy_bytes 1064 <backup-$idx >$objdir/pack/$idx &&
git -c core.multiPackIndex=true rev-list --objects --all 2>err &&
test_must_be_empty err
'
test_expect_success 'add more objects' '
for i in $(test_seq 6 10)
do
generate_objects $i
done &&
commit_and_list_objects
'
test_expect_success 'write midx with two packs' '
git pack-objects --index-version=1 $objdir/pack/test-2 <obj-list &&
git multi-pack-index --object-dir=$objdir write &&
midx_read_expect 2 34 4 $objdir
'
compare_results_with_midx "two packs"
test_expect_success 'write progress off for redirected stderr' '
git multi-pack-index --object-dir=$objdir write 2>err &&
test_line_count = 0 err
'
test_expect_success 'write force progress on for stderr' '
git multi-pack-index --object-dir=$objdir --progress write 2>err &&
test_file_not_empty err
'
test_expect_success 'write with the --no-progress option' '
git multi-pack-index --object-dir=$objdir --no-progress write 2>err &&
test_line_count = 0 err
'
test_expect_success 'add more packs' '
for j in $(test_seq 11 20)
do
generate_objects $j &&
commit_and_list_objects &&
git pack-objects --index-version=2 $objdir/pack/test-pack <obj-list
done
'
compare_results_with_midx "mixed mode (two packs + extra)"
test_expect_success 'write midx with twelve packs' '
git multi-pack-index --object-dir=$objdir write &&
midx_read_expect 12 74 4 $objdir
'
compare_results_with_midx "twelve packs"
test_expect_success 'verify multi-pack-index success' '
git multi-pack-index verify --object-dir=$objdir
'
test_expect_success 'verify progress off for redirected stderr' '
git multi-pack-index verify --object-dir=$objdir 2>err &&
test_line_count = 0 err
'
test_expect_success 'verify force progress on for stderr' '
git multi-pack-index verify --object-dir=$objdir --progress 2>err &&
test_file_not_empty err
'
test_expect_success 'verify with the --no-progress option' '
git multi-pack-index verify --object-dir=$objdir --no-progress 2>err &&
test_line_count = 0 err
'
# usage: corrupt_midx_and_verify <pos> <data> <objdir> <string>
corrupt_midx_and_verify() {
POS=$1 &&
DATA="${2:-\0}" &&
OBJDIR=$3 &&
GREPSTR="$4" &&
COMMAND="$5" &&
if test -z "$COMMAND"
then
COMMAND="git multi-pack-index verify --object-dir=$OBJDIR"
fi &&
FILE=$OBJDIR/pack/multi-pack-index &&
chmod a+w $FILE &&
test_when_finished mv midx-backup $FILE &&
cp $FILE midx-backup &&
printf "$DATA" | dd of="$FILE" bs=1 seek="$POS" conv=notrunc &&
test_must_fail $COMMAND 2>test_err &&
grep -v "^+" test_err >err &&
test_i18ngrep "$GREPSTR" err
}
test_expect_success 'verify bad signature' '
corrupt_midx_and_verify 0 "\00" $objdir \
"multi-pack-index signature"
'
HASH_LEN=$(test_oid rawsz)
NUM_OBJECTS=74
MIDX_BYTE_VERSION=4
MIDX_BYTE_OID_VERSION=5
MIDX_BYTE_CHUNK_COUNT=6
MIDX_HEADER_SIZE=12
MIDX_BYTE_CHUNK_ID=$MIDX_HEADER_SIZE
MIDX_BYTE_CHUNK_OFFSET=$(($MIDX_HEADER_SIZE + 4))
MIDX_NUM_CHUNKS=5
MIDX_CHUNK_LOOKUP_WIDTH=12
MIDX_OFFSET_PACKNAMES=$(($MIDX_HEADER_SIZE + \
$MIDX_NUM_CHUNKS * $MIDX_CHUNK_LOOKUP_WIDTH))
MIDX_BYTE_PACKNAME_ORDER=$(($MIDX_OFFSET_PACKNAMES + 2))
MIDX_OFFSET_OID_FANOUT=$(($MIDX_OFFSET_PACKNAMES + $(test_oid packnameoff)))
MIDX_OID_FANOUT_WIDTH=4
MIDX_BYTE_OID_FANOUT_ORDER=$((MIDX_OFFSET_OID_FANOUT + 250 * $MIDX_OID_FANOUT_WIDTH + $(test_oid fanoutoff)))
MIDX_OFFSET_OID_LOOKUP=$(($MIDX_OFFSET_OID_FANOUT + 256 * $MIDX_OID_FANOUT_WIDTH))
MIDX_BYTE_OID_LOOKUP=$(($MIDX_OFFSET_OID_LOOKUP + 16 * $HASH_LEN))
MIDX_OFFSET_OBJECT_OFFSETS=$(($MIDX_OFFSET_OID_LOOKUP + $NUM_OBJECTS * $HASH_LEN))
MIDX_OFFSET_WIDTH=8
MIDX_BYTE_PACK_INT_ID=$(($MIDX_OFFSET_OBJECT_OFFSETS + 16 * $MIDX_OFFSET_WIDTH + 2))
MIDX_BYTE_OFFSET=$(($MIDX_OFFSET_OBJECT_OFFSETS + 16 * $MIDX_OFFSET_WIDTH + 6))
test_expect_success 'verify bad version' '
corrupt_midx_and_verify $MIDX_BYTE_VERSION "\00" $objdir \
"multi-pack-index version"
'
test_expect_success 'verify bad OID version' '
corrupt_midx_and_verify $MIDX_BYTE_OID_VERSION "\02" $objdir \
"hash version"
'
test_expect_success 'verify truncated chunk count' '
corrupt_midx_and_verify $MIDX_BYTE_CHUNK_COUNT "\01" $objdir \
"missing required"
'
test_expect_success 'verify extended chunk count' '
corrupt_midx_and_verify $MIDX_BYTE_CHUNK_COUNT "\07" $objdir \
"terminating multi-pack-index chunk id appears earlier than expected"
'
test_expect_success 'verify missing required chunk' '
corrupt_midx_and_verify $MIDX_BYTE_CHUNK_ID "\01" $objdir \
"missing required"
'
test_expect_success 'verify invalid chunk offset' '
corrupt_midx_and_verify $MIDX_BYTE_CHUNK_OFFSET "\01" $objdir \
"invalid chunk offset (too large)"
'
test_expect_success 'verify packnames out of order' '
corrupt_midx_and_verify $MIDX_BYTE_PACKNAME_ORDER "z" $objdir \
"pack names out of order"
'
test_expect_success 'verify packnames out of order' '
corrupt_midx_and_verify $MIDX_BYTE_PACKNAME_ORDER "a" $objdir \
"failed to load pack"
'
test_expect_success 'verify oid fanout out of order' '
corrupt_midx_and_verify $MIDX_BYTE_OID_FANOUT_ORDER "\01" $objdir \
"oid fanout out of order"
'
test_expect_success 'verify oid lookup out of order' '
corrupt_midx_and_verify $MIDX_BYTE_OID_LOOKUP "\00" $objdir \
"oid lookup out of order"
'
test_expect_success 'verify incorrect pack-int-id' '
corrupt_midx_and_verify $MIDX_BYTE_PACK_INT_ID "\07" $objdir \
"bad pack-int-id"
'
test_expect_success 'verify incorrect offset' '
corrupt_midx_and_verify $MIDX_BYTE_OFFSET "\377" $objdir \
"incorrect object offset"
'
test_expect_success 'git-fsck incorrect offset' '
corrupt_midx_and_verify $MIDX_BYTE_OFFSET "\377" $objdir \
"incorrect object offset" \
"git -c core.multipackindex=true fsck"
'
test_expect_success 'repack progress off for redirected stderr' '
git multi-pack-index --object-dir=$objdir repack 2>err &&
test_line_count = 0 err
'
test_expect_success 'repack force progress on for stderr' '
git multi-pack-index --object-dir=$objdir --progress repack 2>err &&
test_file_not_empty err
'
test_expect_success 'repack with the --no-progress option' '
git multi-pack-index --object-dir=$objdir --no-progress repack 2>err &&
test_line_count = 0 err
'
test_expect_success 'repack removes multi-pack-index' '
test_path_is_file $objdir/pack/multi-pack-index &&
GIT_TEST_MULTI_PACK_INDEX=0 git repack -adf &&
test_path_is_missing $objdir/pack/multi-pack-index
'
compare_results_with_midx "after repack"
test_expect_success 'multi-pack-index and pack-bitmap' '
git -c repack.writeBitmaps=true repack -ad &&
git multi-pack-index write &&
git rev-list --test-bitmap HEAD
'
test_expect_success 'multi-pack-index and alternates' '
git init --bare alt.git &&
echo $(pwd)/alt.git/objects >.git/objects/info/alternates &&
echo content1 >file1 &&
altblob=$(GIT_DIR=alt.git git hash-object -w file1) &&
git cat-file blob $altblob &&
git rev-list --all
'
compare_results_with_midx "with alternate (local midx)"
test_expect_success 'multi-pack-index in an alternate' '
mv .git/objects/pack/* alt.git/objects/pack &&
test_commit add_local_objects &&
git repack --local &&
git multi-pack-index write &&
midx_read_expect 1 3 4 $objdir &&
git reset --hard HEAD~1 &&
rm -f .git/objects/pack/*
'
compare_results_with_midx "with alternate (remote midx)"
# usage: corrupt_data <file> <pos> [<data>]
corrupt_data () {
file=$1
pos=$2
data="${3:-\0}"
printf "$data" | dd of="$file" bs=1 seek="$pos" conv=notrunc
}
# Force 64-bit offsets by manipulating the idx file.
# This makes the IDX file _incorrect_ so be careful to clean up after!
test_expect_success 'force some 64-bit offsets with pack-objects' '
mkdir objects64 &&
mkdir objects64/pack &&
for i in $(test_seq 1 11)
do
generate_objects 11
done &&
commit_and_list_objects &&
pack64=$(git pack-objects --index-version=2,0x40 objects64/pack/test-64 <obj-list) &&
idx64=objects64/pack/test-64-$pack64.idx &&
chmod u+w $idx64 &&
corrupt_data $idx64 $(test_oid idxoff) "\02" &&
midx64=$(git multi-pack-index --object-dir=objects64 write) &&
midx_read_expect 1 63 5 objects64 " large-offsets"
'
test_expect_success 'verify multi-pack-index with 64-bit offsets' '
git multi-pack-index verify --object-dir=objects64
'
NUM_OBJECTS=63
MIDX_OFFSET_OID_FANOUT=$((MIDX_OFFSET_PACKNAMES + 54))
MIDX_OFFSET_OID_LOOKUP=$((MIDX_OFFSET_OID_FANOUT + 256 * $MIDX_OID_FANOUT_WIDTH))
MIDX_OFFSET_OBJECT_OFFSETS=$(($MIDX_OFFSET_OID_LOOKUP + $NUM_OBJECTS * $HASH_LEN))
MIDX_OFFSET_LARGE_OFFSETS=$(($MIDX_OFFSET_OBJECT_OFFSETS + $NUM_OBJECTS * $MIDX_OFFSET_WIDTH))
MIDX_BYTE_LARGE_OFFSET=$(($MIDX_OFFSET_LARGE_OFFSETS + 3))
test_expect_success 'verify incorrect 64-bit offset' '
corrupt_midx_and_verify $MIDX_BYTE_LARGE_OFFSET "\07" objects64 \
"incorrect object offset"
'
test_expect_success 'setup expire tests' '
mkdir dup &&
(
cd dup &&
git init &&
test-tool genrandom "data" 4096 >large_file.txt &&
git update-index --add large_file.txt &&
for i in $(test_seq 1 20)
do
test_commit $i
done &&
git branch A HEAD &&
git branch B HEAD~8 &&
git branch C HEAD~13 &&
git branch D HEAD~16 &&
git branch E HEAD~18 &&
git pack-objects --revs .git/objects/pack/pack-A <<-EOF &&
refs/heads/A
^refs/heads/B
EOF
git pack-objects --revs .git/objects/pack/pack-B <<-EOF &&
refs/heads/B
^refs/heads/C
EOF
git pack-objects --revs .git/objects/pack/pack-C <<-EOF &&
refs/heads/C
^refs/heads/D
EOF
git pack-objects --revs .git/objects/pack/pack-D <<-EOF &&
refs/heads/D
^refs/heads/E
EOF
git pack-objects --revs .git/objects/pack/pack-E <<-EOF &&
refs/heads/E
EOF
git multi-pack-index write &&
cp -r .git/objects/pack .git/objects/pack-backup
)
'
test_expect_success 'expire does not remove any packs' '
(
cd dup &&
ls .git/objects/pack >expect &&
git multi-pack-index expire &&
ls .git/objects/pack >actual &&
test_cmp expect actual
)
'
test_expect_success 'expire progress off for redirected stderr' '
(
cd dup &&
git multi-pack-index expire 2>err &&
test_line_count = 0 err
)
'
test_expect_success 'expire force progress on for stderr' '
(
cd dup &&
git multi-pack-index --progress expire 2>err &&
test_file_not_empty err
)
'
test_expect_success 'expire with the --no-progress option' '
(
cd dup &&
git multi-pack-index --no-progress expire 2>err &&
test_line_count = 0 err
)
'
test_expect_success 'expire removes unreferenced packs' '
(
cd dup &&
git pack-objects --revs .git/objects/pack/pack-combined <<-EOF &&
refs/heads/A
^refs/heads/C
EOF
git multi-pack-index write &&
ls .git/objects/pack | grep -v -e pack-[AB] >expect &&
git multi-pack-index expire &&
ls .git/objects/pack >actual &&
test_cmp expect actual &&
ls .git/objects/pack/ | grep idx >expect-idx &&
test-tool read-midx .git/objects | grep idx >actual-midx &&
test_cmp expect-idx actual-midx &&
git multi-pack-index verify &&
git fsck
)
'
test_expect_success 'repack with minimum size does not alter existing packs' '
(
cd dup &&
rm -rf .git/objects/pack &&
mv .git/objects/pack-backup .git/objects/pack &&
test-tool chmtime =-5 .git/objects/pack/pack-D* &&
test-tool chmtime =-4 .git/objects/pack/pack-C* &&
test-tool chmtime =-3 .git/objects/pack/pack-B* &&
test-tool chmtime =-2 .git/objects/pack/pack-A* &&
ls .git/objects/pack >expect &&
MINSIZE=$(test-tool path-utils file-size .git/objects/pack/*pack | sort -n | head -n 1) &&
git multi-pack-index repack --batch-size=$MINSIZE &&
ls .git/objects/pack >actual &&
test_cmp expect actual
)
'
test_expect_success 'repack respects repack.packKeptObjects=false' '
test_when_finished rm -f dup/.git/objects/pack/*keep &&
(
cd dup &&
ls .git/objects/pack/*idx >idx-list &&
test_line_count = 5 idx-list &&
ls .git/objects/pack/*.pack | sed "s/\.pack/.keep/" >keep-list &&
test_line_count = 5 keep-list &&
for keep in $(cat keep-list)
do
touch $keep || return 1
done &&
git multi-pack-index repack --batch-size=0 &&
ls .git/objects/pack/*idx >idx-list &&
test_line_count = 5 idx-list &&
test-tool read-midx .git/objects | grep idx >midx-list &&
test_line_count = 5 midx-list &&
THIRD_SMALLEST_SIZE=$(test-tool path-utils file-size .git/objects/pack/*pack | sort -n | sed -n 3p) &&
BATCH_SIZE=$((THIRD_SMALLEST_SIZE + 1)) &&
git multi-pack-index repack --batch-size=$BATCH_SIZE &&
ls .git/objects/pack/*idx >idx-list &&
test_line_count = 5 idx-list &&
test-tool read-midx .git/objects | grep idx >midx-list &&
test_line_count = 5 midx-list
)
'
test_expect_success 'repack creates a new pack' '
(
cd dup &&
ls .git/objects/pack/*idx >idx-list &&
test_line_count = 5 idx-list &&
THIRD_SMALLEST_SIZE=$(test-tool path-utils file-size .git/objects/pack/*pack | sort -n | head -n 3 | tail -n 1) &&
BATCH_SIZE=$(($THIRD_SMALLEST_SIZE + 1)) &&
git multi-pack-index repack --batch-size=$BATCH_SIZE &&
ls .git/objects/pack/*idx >idx-list &&
test_line_count = 6 idx-list &&
test-tool read-midx .git/objects | grep idx >midx-list &&
test_line_count = 6 midx-list
)
'
test_expect_success 'expire removes repacked packs' '
(
cd dup &&
ls -al .git/objects/pack/*pack &&
ls -S .git/objects/pack/*pack | head -n 4 >expect &&
git multi-pack-index expire &&
ls -S .git/objects/pack/*pack >actual &&
test_cmp expect actual &&
test-tool read-midx .git/objects | grep idx >midx-list &&
test_line_count = 4 midx-list
)
'
test_expect_success 'expire works when adding new packs' '
(
cd dup &&
git pack-objects --revs .git/objects/pack/pack-combined <<-EOF &&
refs/heads/A
^refs/heads/B
EOF
git pack-objects --revs .git/objects/pack/pack-combined <<-EOF &&
refs/heads/B
^refs/heads/C
EOF
git pack-objects --revs .git/objects/pack/pack-combined <<-EOF &&
refs/heads/C
^refs/heads/D
EOF
git multi-pack-index write &&
git pack-objects --revs .git/objects/pack/a-pack <<-EOF &&
refs/heads/D
^refs/heads/E
EOF
git multi-pack-index write &&
git pack-objects --revs .git/objects/pack/z-pack <<-EOF &&
refs/heads/E
EOF
git multi-pack-index expire &&
ls .git/objects/pack/ | grep idx >expect &&
test-tool read-midx .git/objects | grep idx >actual &&
test_cmp expect actual &&
git multi-pack-index verify
)
'
test_expect_success 'expire respects .keep files' '
(
cd dup &&
git pack-objects --revs .git/objects/pack/pack-all <<-EOF &&
refs/heads/A
EOF
git multi-pack-index write &&
PACKA=$(ls .git/objects/pack/a-pack*\.pack | sed s/\.pack\$//) &&
touch $PACKA.keep &&
git multi-pack-index expire &&
ls -S .git/objects/pack/a-pack* | grep $PACKA >a-pack-files &&
test_line_count = 3 a-pack-files &&
test-tool read-midx .git/objects | grep idx >midx-list &&
test_line_count = 2 midx-list
)
'
test_expect_success 'repack --batch-size=0 repacks everything' '
(
cd dup &&
rm .git/objects/pack/*.keep &&
ls .git/objects/pack/*idx >idx-list &&
test_line_count = 2 idx-list &&
git multi-pack-index repack --batch-size=0 &&
ls .git/objects/pack/*idx >idx-list &&
test_line_count = 3 idx-list &&
test-tool read-midx .git/objects | grep idx >midx-list &&
test_line_count = 3 midx-list &&
git multi-pack-index expire &&
ls -al .git/objects/pack/*idx >idx-list &&
test_line_count = 1 idx-list &&
git multi-pack-index repack --batch-size=0 &&
ls -al .git/objects/pack/*idx >new-idx-list &&
test_cmp idx-list new-idx-list
)
'
test_done
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