X-Git-Url: https://git.madduck.net/etc/vim.git/blobdiff_plain/9f096d55365cb63548eef97e254c2793ae2776a0..2d9eaafa97e967c8974a6321dcc442a90192140f:/tests/test_black.py

diff --git a/tests/test_black.py b/tests/test_black.py
index 02926d1..5e17faf 100644
--- a/tests/test_black.py
+++ b/tests/test_black.py
@@ -636,6 +636,12 @@ class BlackTestCase(unittest.TestCase):
             )
             self.assertEqual(result.exit_code, 1)
 
+    def test_no_files(self) -> None:
+        with cache_dir():
+            # Without an argument, black exits with error code 0.
+            result = CliRunner().invoke(black.main, [])
+            self.assertEqual(result.exit_code, 0)
+
     def test_read_cache_line_lengths(self) -> None:
         with cache_dir() as workspace:
             path = (workspace / "file.py").resolve()