builtin/commit.c: extract ignore_non_trailer() helper function

diff --git a/t/t4111-apply-subdir.sh b/t/t4111-apply-subdir.sh
index 7c398432bad761c1b38c6d15548bed0c389221fd..1618a6dbc7c718677cf669b5f6fc96f2682992fb 100755 (executable)
--- a/t/t4111-apply-subdir.sh
+++ b/t/t4111-apply-subdir.sh
@@ -86,6 +86,20 @@ test_expect_success 'apply --index from subdir of toplevel' '
        test_cmp expected sub/dir/file
 '
 
+test_expect_success 'apply half-broken patch from subdir of toplevel' '
+       (
+               cd sub/dir &&
+               test_must_fail git apply <<-EOF
+               --- sub/dir/file
+               +++ sub/dir/file
+               @@ -1,0 +1,0 @@
+               --- file_in_root
+               +++ file_in_root
+               @@ -1,0 +1,0 @@
+               EOF
+       )
+'
+
 test_expect_success 'apply from .git dir' '
        cp postimage expected &&
        cp preimage .git/file &&