> diff --git a/t/t5310-pack-bitmaps.sh b/t/t5310-pack-bitmaps.sh > index 423c0a475f..237ee6e5fc 100755 > --- a/t/t5310-pack-bitmaps.sh > +++ b/t/t5310-pack-bitmaps.sh > @@ -331,4 +331,17 @@ test_expect_success 'pack reuse respects --incremental' ' > git show-index <empty.idx >actual && > test_cmp expect actual > ' > + > +test_expect_success 'truncated bitmap fails gracefully' ' > + git repack -ad && > + git rev-list --use-bitmap-index --count --all >expect && > + bitmap=$(ls .git/objects/pack/*.bitmap) && > + test_when_finished "rm -f $bitmap" && > + head -c 512 <$bitmap >$bitmap.tmp && > + mv $bitmap.tmp $bitmap && This line turns out to be problematic on OSX and ultimately causes the test to fail. When OSX's 'mv's destination is read-only, it asks whether to replace the destination even though in the test its stdin is not a terminal (and thus doesn't conform to POSIX[1]). Since the '.bitmap' file is read-only, and since 'mv' obviously doesn't get an affirmative response from /dev/null, the original '.bitmap' file is not overwritten, the subsequent 'git rev-list' doesn't print any error message, and finally 'test_i18ngrep' causes the test to fail. The relevant part of the '-x' test output on Travis CI: ++mv .git/objects/pack/pack-8886db3fce4f9657c1a43fee7d3ea4f2a4b5be2d.bitmap.tmp .git/objects/pack/pack-8886db3fce4f9657c1a43fee7d3ea4f2a4b5be2d.bitmap override r--r--r-- travis/staff for .git/objects/pack/pack-8886db3fce4f9657c1a43fee7d3ea4f2a4b5be2d.bitmap? (y/n [n]) not overwritten ++git rev-list --use-bitmap-index --count --all ++test_cmp expect actual ++diff -u expect actual ++test_i18ngrep corrupt stderr ++eval 'last_arg=${2}' +++last_arg=stderr ++test -f stderr ++test 2 -lt 2 ++test 'x!' = xcorrupt ++test -n '' ++test 'x!' = xcorrupt ++grep corrupt stderr ++echo 'error: '\''grep corrupt' 'stderr'\'' didn'\''t find a match in:' error: 'grep corrupt stderr' didn't find a match in: ++test -s stderr ++echo '<File '\''stderr'\'' is empty>' <File 'stderr' is empty> ++return 1 error: last command exited with $?=1 not ok 43 - truncated bitmap fails gracefully As far as I can tell, 'mv -f' appears to make the test work on OSX as well. I've run a build job with an additional 'grep ^override t/test-results/*.out' command following the tests to see whether there are any other cases where OSX 'mv' doesn't overwrite a read-only file without causing the tests to fail, but found nothing. (But note that the OSX build jobs don't run all tests.) [1] http://pubs.opengroup.org/onlinepubs/9699919799/utilities/mv.html > + git rev-list --use-bitmap-index --count --all >actual 2>stderr && > + test_cmp expect actual && > + test_i18ngrep corrupt stderr > +' > +