untracked-cache: be defensive about missing NULs in index

diff --git a/t/t7607-merge-overwrite.sh b/t/t7607-merge-overwrite.sh
index 9444d6a9b9026748028178c4b66ee8bbbc1d89fa..dd8ab7ede182fc3c3da840fee083bf23a94ce13c 100755 (executable)
--- a/t/t7607-merge-overwrite.sh
+++ b/t/t7607-merge-overwrite.sh
@@ -92,12 +92,15 @@ test_expect_success 'will not overwrite removed file with staged changes' '
        test_cmp important c1.c
 '
 
-test_expect_failure 'will not overwrite unstaged changes in renamed file' '
+test_expect_success 'will not overwrite unstaged changes in renamed file' '
        git reset --hard c1 &&
        git mv c1.c other.c &&
        git commit -m rename &&
        cp important other.c &&
-       git merge c1a &&
+       test_must_fail git merge c1a >out &&
+       test_i18ngrep "Refusing to lose dirty file at other.c" out &&
+       test_path_is_file other.c~HEAD &&
+       test $(git hash-object other.c~HEAD) = $(git rev-parse c1a:c1.c) &&
        test_cmp important other.c
 '