git/t/t1450-fsck.sh
Jonathan Tan a7c28a2161 tests: ensure fsck fails on corrupt packfiles
t1450-fsck.sh does not have a test that checks fsck's behavior when a
packfile is invalid. It does have a test for when an object in a
packfile is invalid, but in that test, the packfile itself is valid.

Add such a test.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-28 15:26:48 -07:00

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Executable file

#!/bin/sh
test_description='git fsck random collection of tests
* (HEAD) B
* (master) A
'
. ./test-lib.sh
test_expect_success setup '
git config gc.auto 0 &&
git config i18n.commitencoding ISO-8859-1 &&
test_commit A fileA one &&
git config --unset i18n.commitencoding &&
git checkout HEAD^0 &&
test_commit B fileB two &&
git tag -d A B &&
git reflog expire --expire=now --all &&
>empty
'
test_expect_success 'loose objects borrowed from alternate are not missing' '
mkdir another &&
(
cd another &&
git init &&
echo ../../../.git/objects >.git/objects/info/alternates &&
test_commit C fileC one &&
git fsck --no-dangling >../actual 2>&1
) &&
test_cmp empty actual
'
test_expect_success 'HEAD is part of refs, valid objects appear valid' '
git fsck >actual 2>&1 &&
test_cmp empty actual
'
# Corruption tests follow. Make sure to remove all traces of the
# specific corruption you test afterwards, lest a later test trip over
# it.
test_expect_success 'setup: helpers for corruption tests' '
sha1_file() {
remainder=${1#??} &&
firsttwo=${1%$remainder} &&
echo ".git/objects/$firsttwo/$remainder"
} &&
remove_object() {
rm "$(sha1_file "$1")"
}
'
test_expect_success 'object with bad sha1' '
sha=$(echo blob | git hash-object -w --stdin) &&
old=$(echo $sha | sed "s+^..+&/+") &&
new=$(dirname $old)/ffffffffffffffffffffffffffffffffffffff &&
sha="$(dirname $new)$(basename $new)" &&
mv .git/objects/$old .git/objects/$new &&
test_when_finished "remove_object $sha" &&
git update-index --add --cacheinfo 100644 $sha foo &&
test_when_finished "git read-tree -u --reset HEAD" &&
tree=$(git write-tree) &&
test_when_finished "remove_object $tree" &&
cmt=$(echo bogus | git commit-tree $tree) &&
test_when_finished "remove_object $cmt" &&
git update-ref refs/heads/bogus $cmt &&
test_when_finished "git update-ref -d refs/heads/bogus" &&
test_must_fail git fsck 2>out &&
cat out &&
grep "$sha.*corrupt" out
'
test_expect_success 'branch pointing to non-commit' '
git rev-parse HEAD^{tree} >.git/refs/heads/invalid &&
test_when_finished "git update-ref -d refs/heads/invalid" &&
test_must_fail git fsck 2>out &&
cat out &&
grep "not a commit" out
'
test_expect_success 'HEAD link pointing at a funny object' '
test_when_finished "mv .git/SAVED_HEAD .git/HEAD" &&
mv .git/HEAD .git/SAVED_HEAD &&
echo 0000000000000000000000000000000000000000 >.git/HEAD &&
# avoid corrupt/broken HEAD from interfering with repo discovery
test_must_fail env GIT_DIR=.git git fsck 2>out &&
cat out &&
grep "detached HEAD points" out
'
test_expect_success 'HEAD link pointing at a funny place' '
test_when_finished "mv .git/SAVED_HEAD .git/HEAD" &&
mv .git/HEAD .git/SAVED_HEAD &&
echo "ref: refs/funny/place" >.git/HEAD &&
# avoid corrupt/broken HEAD from interfering with repo discovery
test_must_fail env GIT_DIR=.git git fsck 2>out &&
cat out &&
grep "HEAD points to something strange" out
'
test_expect_success 'email without @ is okay' '
git cat-file commit HEAD >basis &&
sed "s/@/AT/" basis >okay &&
new=$(git hash-object -t commit -w --stdin <okay) &&
test_when_finished "remove_object $new" &&
git update-ref refs/heads/bogus "$new" &&
test_when_finished "git update-ref -d refs/heads/bogus" &&
git fsck 2>out &&
cat out &&
! grep "commit $new" out
'
test_expect_success 'email with embedded > is not okay' '
git cat-file commit HEAD >basis &&
sed "s/@[a-z]/&>/" basis >bad-email &&
new=$(git hash-object -t commit -w --stdin <bad-email) &&
test_when_finished "remove_object $new" &&
git update-ref refs/heads/bogus "$new" &&
test_when_finished "git update-ref -d refs/heads/bogus" &&
test_must_fail git fsck 2>out &&
cat out &&
grep "error in commit $new" out
'
test_expect_success 'missing < email delimiter is reported nicely' '
git cat-file commit HEAD >basis &&
sed "s/<//" basis >bad-email-2 &&
new=$(git hash-object -t commit -w --stdin <bad-email-2) &&
test_when_finished "remove_object $new" &&
git update-ref refs/heads/bogus "$new" &&
test_when_finished "git update-ref -d refs/heads/bogus" &&
test_must_fail git fsck 2>out &&
cat out &&
grep "error in commit $new.* - bad name" out
'
test_expect_success 'missing email is reported nicely' '
git cat-file commit HEAD >basis &&
sed "s/[a-z]* <[^>]*>//" basis >bad-email-3 &&
new=$(git hash-object -t commit -w --stdin <bad-email-3) &&
test_when_finished "remove_object $new" &&
git update-ref refs/heads/bogus "$new" &&
test_when_finished "git update-ref -d refs/heads/bogus" &&
test_must_fail git fsck 2>out &&
cat out &&
grep "error in commit $new.* - missing email" out
'
test_expect_success '> in name is reported' '
git cat-file commit HEAD >basis &&
sed "s/ </> </" basis >bad-email-4 &&
new=$(git hash-object -t commit -w --stdin <bad-email-4) &&
test_when_finished "remove_object $new" &&
git update-ref refs/heads/bogus "$new" &&
test_when_finished "git update-ref -d refs/heads/bogus" &&
test_must_fail git fsck 2>out &&
cat out &&
grep "error in commit $new" out
'
# date is 2^64 + 1
test_expect_success 'integer overflow in timestamps is reported' '
git cat-file commit HEAD >basis &&
sed "s/^\\(author .*>\\) [0-9]*/\\1 18446744073709551617/" \
<basis >bad-timestamp &&
new=$(git hash-object -t commit -w --stdin <bad-timestamp) &&
test_when_finished "remove_object $new" &&
git update-ref refs/heads/bogus "$new" &&
test_when_finished "git update-ref -d refs/heads/bogus" &&
test_must_fail git fsck 2>out &&
cat out &&
grep "error in commit $new.*integer overflow" out
'
test_expect_success 'commit with NUL in header' '
git cat-file commit HEAD >basis &&
sed "s/author ./author Q/" <basis | q_to_nul >commit-NUL-header &&
new=$(git hash-object -t commit -w --stdin <commit-NUL-header) &&
test_when_finished "remove_object $new" &&
git update-ref refs/heads/bogus "$new" &&
test_when_finished "git update-ref -d refs/heads/bogus" &&
test_must_fail git fsck 2>out &&
cat out &&
grep "error in commit $new.*unterminated header: NUL at offset" out
'
test_expect_success 'tree object with duplicate entries' '
test_when_finished "for i in \$T; do remove_object \$i; done" &&
T=$(
GIT_INDEX_FILE=test-index &&
export GIT_INDEX_FILE &&
rm -f test-index &&
>x &&
git add x &&
git rev-parse :x &&
T=$(git write-tree) &&
echo $T &&
(
git cat-file tree $T &&
git cat-file tree $T
) |
git hash-object -w -t tree --stdin
) &&
test_must_fail git fsck 2>out &&
grep "error in tree .*contains duplicate file entries" out
'
test_expect_success 'unparseable tree object' '
test_when_finished "git update-ref -d refs/heads/wrong" &&
test_when_finished "remove_object \$tree_sha1" &&
test_when_finished "remove_object \$commit_sha1" &&
tree_sha1=$(printf "100644 \0twenty-bytes-of-junk" | git hash-object -t tree --stdin -w --literally) &&
commit_sha1=$(git commit-tree $tree_sha1) &&
git update-ref refs/heads/wrong $commit_sha1 &&
test_must_fail git fsck 2>out &&
test_i18ngrep "error: empty filename in tree entry" out &&
test_i18ngrep "$tree_sha1" out &&
test_i18ngrep ! "fatal: empty filename in tree entry" out
'
test_expect_success 'tag pointing to nonexistent' '
cat >invalid-tag <<-\EOF &&
object ffffffffffffffffffffffffffffffffffffffff
type commit
tag invalid
tagger T A Gger <tagger@example.com> 1234567890 -0000
This is an invalid tag.
EOF
tag=$(git hash-object -t tag -w --stdin <invalid-tag) &&
test_when_finished "remove_object $tag" &&
echo $tag >.git/refs/tags/invalid &&
test_when_finished "git update-ref -d refs/tags/invalid" &&
test_must_fail git fsck --tags >out &&
cat out &&
grep "broken link" out
'
test_expect_success 'tag pointing to something else than its type' '
sha=$(echo blob | git hash-object -w --stdin) &&
test_when_finished "remove_object $sha" &&
cat >wrong-tag <<-EOF &&
object $sha
type commit
tag wrong
tagger T A Gger <tagger@example.com> 1234567890 -0000
This is an invalid tag.
EOF
tag=$(git hash-object -t tag -w --stdin <wrong-tag) &&
test_when_finished "remove_object $tag" &&
echo $tag >.git/refs/tags/wrong &&
test_when_finished "git update-ref -d refs/tags/wrong" &&
test_must_fail git fsck --tags
'
test_expect_success 'tag with incorrect tag name & missing tagger' '
sha=$(git rev-parse HEAD) &&
cat >wrong-tag <<-EOF &&
object $sha
type commit
tag wrong name format
This is an invalid tag.
EOF
tag=$(git hash-object -t tag -w --stdin <wrong-tag) &&
test_when_finished "remove_object $tag" &&
echo $tag >.git/refs/tags/wrong &&
test_when_finished "git update-ref -d refs/tags/wrong" &&
git fsck --tags 2>out &&
cat >expect <<-EOF &&
warning in tag $tag: badTagName: invalid '\''tag'\'' name: wrong name format
warning in tag $tag: missingTaggerEntry: invalid format - expected '\''tagger'\'' line
EOF
test_cmp expect out
'
test_expect_success 'tag with bad tagger' '
sha=$(git rev-parse HEAD) &&
cat >wrong-tag <<-EOF &&
object $sha
type commit
tag not-quite-wrong
tagger Bad Tagger Name
This is an invalid tag.
EOF
tag=$(git hash-object --literally -t tag -w --stdin <wrong-tag) &&
test_when_finished "remove_object $tag" &&
echo $tag >.git/refs/tags/wrong &&
test_when_finished "git update-ref -d refs/tags/wrong" &&
test_must_fail git fsck --tags 2>out &&
grep "error in tag .*: invalid author/committer" out
'
test_expect_success 'tag with NUL in header' '
sha=$(git rev-parse HEAD) &&
q_to_nul >tag-NUL-header <<-EOF &&
object $sha
type commit
tag contains-Q-in-header
tagger T A Gger <tagger@example.com> 1234567890 -0000
This is an invalid tag.
EOF
tag=$(git hash-object --literally -t tag -w --stdin <tag-NUL-header) &&
test_when_finished "remove_object $tag" &&
echo $tag >.git/refs/tags/wrong &&
test_when_finished "git update-ref -d refs/tags/wrong" &&
test_must_fail git fsck --tags 2>out &&
cat out &&
grep "error in tag $tag.*unterminated header: NUL at offset" out
'
test_expect_success 'cleaned up' '
git fsck >actual 2>&1 &&
test_cmp empty actual
'
test_expect_success 'rev-list --verify-objects' '
git rev-list --verify-objects --all >/dev/null 2>out &&
test_cmp empty out
'
test_expect_success 'rev-list --verify-objects with bad sha1' '
sha=$(echo blob | git hash-object -w --stdin) &&
old=$(echo $sha | sed "s+^..+&/+") &&
new=$(dirname $old)/ffffffffffffffffffffffffffffffffffffff &&
sha="$(dirname $new)$(basename $new)" &&
mv .git/objects/$old .git/objects/$new &&
test_when_finished "remove_object $sha" &&
git update-index --add --cacheinfo 100644 $sha foo &&
test_when_finished "git read-tree -u --reset HEAD" &&
tree=$(git write-tree) &&
test_when_finished "remove_object $tree" &&
cmt=$(echo bogus | git commit-tree $tree) &&
test_when_finished "remove_object $cmt" &&
git update-ref refs/heads/bogus $cmt &&
test_when_finished "git update-ref -d refs/heads/bogus" &&
test_might_fail git rev-list --verify-objects refs/heads/bogus >/dev/null 2>out &&
cat out &&
grep -q "error: sha1 mismatch 63ffffffffffffffffffffffffffffffffffffff" out
'
test_expect_success 'force fsck to ignore double author' '
git cat-file commit HEAD >basis &&
sed "s/^author .*/&,&/" <basis | tr , \\n >multiple-authors &&
new=$(git hash-object -t commit -w --stdin <multiple-authors) &&
test_when_finished "remove_object $new" &&
git update-ref refs/heads/bogus "$new" &&
test_when_finished "git update-ref -d refs/heads/bogus" &&
test_must_fail git fsck &&
git -c fsck.multipleAuthors=ignore fsck
'
_bz='\0'
_bz5="$_bz$_bz$_bz$_bz$_bz"
_bz20="$_bz5$_bz5$_bz5$_bz5"
test_expect_success 'fsck notices blob entry pointing to null sha1' '
(git init null-blob &&
cd null-blob &&
sha=$(printf "100644 file$_bz$_bz20" |
git hash-object -w --stdin -t tree) &&
git fsck 2>out &&
cat out &&
grep "warning.*null sha1" out
)
'
test_expect_success 'fsck notices submodule entry pointing to null sha1' '
(git init null-commit &&
cd null-commit &&
sha=$(printf "160000 submodule$_bz$_bz20" |
git hash-object -w --stdin -t tree) &&
git fsck 2>out &&
cat out &&
grep "warning.*null sha1" out
)
'
while read name path pretty; do
while read mode type; do
: ${pretty:=$path}
test_expect_success "fsck notices $pretty as $type" '
(
git init $name-$type &&
cd $name-$type &&
echo content >file &&
git add file &&
git commit -m base &&
blob=$(git rev-parse :file) &&
tree=$(git rev-parse HEAD^{tree}) &&
value=$(eval "echo \$$type") &&
printf "$mode $type %s\t%s" "$value" "$path" >bad &&
bad_tree=$(git mktree <bad) &&
git fsck 2>out &&
cat out &&
grep "warning.*tree $bad_tree" out
)'
done <<-\EOF
100644 blob
040000 tree
EOF
done <<-EOF
dot .
dotdot ..
dotgit .git
dotgit-case .GIT
dotgit-unicode .gI${u200c}T .gI{u200c}T
dotgit-case2 .Git
git-tilde1 git~1
dotgitdot .git.
dot-backslash-case .\\\\.GIT\\\\foobar
dotgit-case-backslash .git\\\\foobar
EOF
test_expect_success 'fsck allows .Ňit' '
(
git init not-dotgit &&
cd not-dotgit &&
echo content >file &&
git add file &&
git commit -m base &&
blob=$(git rev-parse :file) &&
printf "100644 blob $blob\t.\\305\\207it" >tree &&
tree=$(git mktree <tree) &&
git fsck 2>err &&
test_line_count = 0 err
)
'
test_expect_success 'NUL in commit' '
rm -fr nul-in-commit &&
git init nul-in-commit &&
(
cd nul-in-commit &&
git commit --allow-empty -m "initial commitQNUL after message" &&
git cat-file commit HEAD >original &&
q_to_nul <original >munged &&
git hash-object -w -t commit --stdin <munged >name &&
git branch bad $(cat name) &&
test_must_fail git -c fsck.nulInCommit=error fsck 2>warn.1 &&
grep nulInCommit warn.1 &&
git fsck 2>warn.2 &&
grep nulInCommit warn.2
)
'
# create a static test repo which is broken by omitting
# one particular object ($1, which is looked up via rev-parse
# in the new repository).
create_repo_missing () {
rm -rf missing &&
git init missing &&
(
cd missing &&
git commit -m one --allow-empty &&
mkdir subdir &&
echo content >subdir/file &&
git add subdir/file &&
git commit -m two &&
unrelated=$(echo unrelated | git hash-object --stdin -w) &&
git tag -m foo tag $unrelated &&
sha1=$(git rev-parse --verify "$1") &&
path=$(echo $sha1 | sed 's|..|&/|') &&
rm .git/objects/$path
)
}
test_expect_success 'fsck notices missing blob' '
create_repo_missing HEAD:subdir/file &&
test_must_fail git -C missing fsck
'
test_expect_success 'fsck notices missing subtree' '
create_repo_missing HEAD:subdir &&
test_must_fail git -C missing fsck
'
test_expect_success 'fsck notices missing root tree' '
create_repo_missing HEAD^{tree} &&
test_must_fail git -C missing fsck
'
test_expect_success 'fsck notices missing parent' '
create_repo_missing HEAD^ &&
test_must_fail git -C missing fsck
'
test_expect_success 'fsck notices missing tagged object' '
create_repo_missing tag^{blob} &&
test_must_fail git -C missing fsck
'
test_expect_success 'fsck notices ref pointing to missing commit' '
create_repo_missing HEAD &&
test_must_fail git -C missing fsck
'
test_expect_success 'fsck notices ref pointing to missing tag' '
create_repo_missing tag &&
test_must_fail git -C missing fsck
'
test_expect_success 'fsck --connectivity-only' '
rm -rf connectivity-only &&
git init connectivity-only &&
(
cd connectivity-only &&
touch empty &&
git add empty &&
test_commit empty &&
# Drop the index now; we want to be sure that we
# recursively notice the broken objects
# because they are reachable from refs, not because
# they are in the index.
rm -f .git/index &&
# corrupt the blob, but in a way that we can still identify
# its type. That lets us see that --connectivity-only is
# not actually looking at the contents, but leaves it
# free to examine the type if it chooses.
empty=.git/objects/e6/9de29bb2d1d6434b8b29ae775ad8c2e48c5391 &&
blob=$(echo unrelated | git hash-object -w --stdin) &&
mv -f $(sha1_file $blob) $empty &&
test_must_fail git fsck --strict &&
git fsck --strict --connectivity-only &&
tree=$(git rev-parse HEAD:) &&
suffix=${tree#??} &&
tree=.git/objects/${tree%$suffix}/$suffix &&
rm -f $tree &&
echo invalid >$tree &&
test_must_fail git fsck --strict --connectivity-only
)
'
test_expect_success 'fsck --connectivity-only with explicit head' '
rm -rf connectivity-only &&
git init connectivity-only &&
(
cd connectivity-only &&
test_commit foo &&
rm -f .git/index &&
tree=$(git rev-parse HEAD^{tree}) &&
remove_object $(git rev-parse HEAD:foo.t) &&
test_must_fail git fsck --connectivity-only $tree
)
'
test_expect_success 'fsck --name-objects' '
rm -rf name-objects &&
git init name-objects &&
(
cd name-objects &&
test_commit julius caesar.t &&
test_commit augustus &&
test_commit caesar &&
remove_object $(git rev-parse julius:caesar.t) &&
test_must_fail git fsck --name-objects >out &&
tree=$(git rev-parse --verify julius:) &&
egrep "$tree \((refs/heads/master|HEAD)@\{[0-9]*\}:" out
)
'
test_expect_success 'alternate objects are correctly blamed' '
test_when_finished "rm -rf alt.git .git/objects/info/alternates" &&
git init --bare alt.git &&
echo "../../alt.git/objects" >.git/objects/info/alternates &&
mkdir alt.git/objects/12 &&
>alt.git/objects/12/34567890123456789012345678901234567890 &&
test_must_fail git fsck >out 2>&1 &&
grep alt.git out
'
test_expect_success 'fsck errors in packed objects' '
git cat-file commit HEAD >basis &&
sed "s/</one/" basis >one &&
sed "s/</foo/" basis >two &&
one=$(git hash-object -t commit -w one) &&
two=$(git hash-object -t commit -w two) &&
pack=$(
{
echo $one &&
echo $two
} | git pack-objects .git/objects/pack/pack
) &&
test_when_finished "rm -f .git/objects/pack/pack-$pack.*" &&
remove_object $one &&
remove_object $two &&
test_must_fail git fsck 2>out &&
grep "error in commit $one.* - bad name" out &&
grep "error in commit $two.* - bad name" out &&
! grep corrupt out
'
test_expect_success 'fsck fails on corrupt packfile' '
hsh=$(git commit-tree -m mycommit HEAD^{tree}) &&
pack=$(echo $hsh | git pack-objects .git/objects/pack/pack) &&
# Corrupt the first byte of the first object. (It contains 3 type bits,
# at least one of which is not zero, so setting the first byte to 0 is
# sufficient.)
chmod a+w .git/objects/pack/pack-$pack.pack &&
printf '\0' | dd of=.git/objects/pack/pack-$pack.pack bs=1 conv=notrunc seek=12 &&
test_when_finished "rm -f .git/objects/pack/pack-$pack.*" &&
remove_object $hsh &&
test_must_fail git fsck 2>out &&
test_i18ngrep "checksum mismatch" out
'
test_expect_success 'fsck finds problems in duplicate loose objects' '
rm -rf broken-duplicate &&
git init broken-duplicate &&
(
cd broken-duplicate &&
test_commit duplicate &&
# no "-d" here, so we end up with duplicates
git repack &&
# now corrupt the loose copy
file=$(sha1_file "$(git rev-parse HEAD)") &&
rm "$file" &&
echo broken >"$file" &&
test_must_fail git fsck
)
'
test_expect_success 'fsck detects trailing loose garbage (commit)' '
git cat-file commit HEAD >basis &&
echo bump-commit-sha1 >>basis &&
commit=$(git hash-object -w -t commit basis) &&
file=$(sha1_file $commit) &&
test_when_finished "remove_object $commit" &&
chmod +w "$file" &&
echo garbage >>"$file" &&
test_must_fail git fsck 2>out &&
test_i18ngrep "garbage.*$commit" out
'
test_expect_success 'fsck detects trailing loose garbage (blob)' '
blob=$(echo trailing | git hash-object -w --stdin) &&
file=$(sha1_file $blob) &&
test_when_finished "remove_object $blob" &&
chmod +w "$file" &&
echo garbage >>"$file" &&
test_must_fail git fsck 2>out &&
test_i18ngrep "garbage.*$blob" out
'
# for each of type, we have one version which is referenced by another object
# (and so while unreachable, not dangling), and another variant which really is
# dangling.
test_expect_success 'fsck notices dangling objects' '
git init dangling &&
(
cd dangling &&
blob=$(echo not-dangling | git hash-object -w --stdin) &&
dblob=$(echo dangling | git hash-object -w --stdin) &&
tree=$(printf "100644 blob %s\t%s\n" $blob one | git mktree) &&
dtree=$(printf "100644 blob %s\t%s\n" $blob two | git mktree) &&
commit=$(git commit-tree $tree) &&
dcommit=$(git commit-tree -p $commit $tree) &&
cat >expect <<-EOF &&
dangling blob $dblob
dangling commit $dcommit
dangling tree $dtree
EOF
git fsck >actual &&
# the output order is non-deterministic, as it comes from a hash
sort <actual >actual.sorted &&
test_cmp expect actual.sorted
)
'
test_expect_success 'fsck $name notices bogus $name' '
test_must_fail git fsck bogus &&
test_must_fail git fsck $_z40
'
test_expect_success 'bogus head does not fallback to all heads' '
# set up a case that will cause a reachability complaint
echo to-be-deleted >foo &&
git add foo &&
blob=$(git rev-parse :foo) &&
test_when_finished "git rm --cached foo" &&
remove_object $blob &&
test_must_fail git fsck $_z40 >out 2>&1 &&
! grep $blob out
'
# Corrupt the checksum on the index.
# Add 1 to the last byte in the SHA.
corrupt_index_checksum () {
perl -w -e '
use Fcntl ":seek";
open my $fh, "+<", ".git/index" or die "open: $!";
binmode $fh;
seek $fh, -1, SEEK_END or die "seek: $!";
read $fh, my $in_byte, 1 or die "read: $!";
$in_value = unpack("C", $in_byte);
$out_value = ($in_value + 1) & 255;
$out_byte = pack("C", $out_value);
seek $fh, -1, SEEK_END or die "seek: $!";
print $fh $out_byte;
close $fh or die "close: $!";
'
}
# Corrupt the checksum on the index and then
# verify that only fsck notices.
test_expect_success 'detect corrupt index file in fsck' '
cp .git/index .git/index.backup &&
test_when_finished "mv .git/index.backup .git/index" &&
corrupt_index_checksum &&
test_must_fail git fsck --cache 2>errors &&
grep "bad index file" errors
'
test_done