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

diff --git a/t/t7607-merge-overwrite.sh b/t/t7607-merge-overwrite.sh
index 6547eb8f5459d4d95113469d338e1879f86b79ea..758a623cdbb5f7e367bcfce5c239d79258c46e84 100755 (executable)
--- a/t/t7607-merge-overwrite.sh
+++ b/t/t7607-merge-overwrite.sh
@@ -141,11 +141,10 @@ test_expect_success SYMLINKS 'will not overwrite untracked symlink in leading pa
        test_path_is_missing .git/MERGE_HEAD
 '
 
-test_expect_success SYMLINKS 'will not be confused by symlink in leading path' '
+test_expect_success 'will not be confused by symlink in leading path' '
        git reset --hard c0 &&
        rm -rf sub &&
-       ln -s sub2 sub &&
-       git add sub &&
+       test_ln_s_add sub2 sub &&
        git commit -m ln &&
        git checkout sub
 '