t1450: avoid use of "sed" on the index, which is a binary file

The previous step added a path zzzzzzzz to the index, and then used
"sed" to replace this string to yyyyyyyy to create a test case where
the checksum at the end of the file does not match the contents.

Unfortunately, use of "sed" on a non-text file is not portable.
Instead, use a Perl script that seeks to the end and modifies the
last byte of the file (where we _know_ stores the trailing
checksum).

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Jeff Hostetler 2017-04-25 18:41:09 +00:00 committed by Junio C Hamano
parent a33fc72fe9
commit 4d9bc37fbe

View File

@ -689,17 +689,35 @@ test_expect_success 'bogus head does not fallback to all heads' '
! 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" &&
echo zzzzzzzz >zzzzzzzz &&
git add zzzzzzzz &&
sed -e "s/zzzzzzzz/yyyyyyyy/" .git/index >.git/index.yyy &&
mv .git/index.yyy .git/index &&
# Confirm that fsck detects invalid checksum
test_must_fail git fsck --cache &&
# Confirm that status no longer complains about invalid checksum
git status
corrupt_index_checksum &&
test_must_fail git fsck --cache 2>errors &&
grep "bad index file" errors
'
test_done