diff --git a/t/t4051-diff-function-context.sh b/t/t4051-diff-function-context.sh
index 2d76a971c4..4838a1df8b 100755
--- a/t/t4051-diff-function-context.sh
+++ b/t/t4051-diff-function-context.sh
@@ -174,7 +174,7 @@ test_expect_success ' context does not include other functions' '
 '
 
 test_expect_success ' context does not include preceding empty lines' '
-	test "$(first_context_line <long_common_tail.diff.diff)" != " "
+	test "$(first_context_line <long_common_tail.diff)" != " "
 '
 
 check_diff changed_hello_appended 'changed function plus appended function'