test_cmp expect actual
'
+test_expect_success 'prune empty collapsed merges' '
+ test_config merge.ff false &&
+ git rev-list HEAD >expect &&
+ test_commit to_remove_2 &&
+ git reset --hard HEAD^ &&
+ test_merge non-ff to_remove_2 &&
+ git filter-branch -f --index-filter "git update-index --remove to_remove_2.t" --prune-empty HEAD &&
+ git rev-list HEAD >actual &&
+ test_cmp expect actual
+'
+
test_expect_success '--remap-to-ancestor with filename filters' '
git checkout master &&
git reset --hard A &&