1 files changed, 50 insertions, 0 deletions
diff --git a/scripts/devscripts/test/test_black.py b/scripts/devscripts/test/test_black.py
new file mode 100644
index 0000000..565018f
--- /dev/null
+++ b/scripts/devscripts/test/test_black.py
@@ -0,0 +1,50 @@
+# Copyright (C) 2021, Benjamin Drung <bdrung@debian.org>
+#
+# Permission to use, copy, modify, and/or distribute this software for any
+# purpose with or without fee is hereby granted, provided that the above
+# copyright notice and this permission notice appear in all copies.
+#
+# THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
+# REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+# AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
+# INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+# LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
+# OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+# PERFORMANCE OF THIS SOFTWARE.
+
+"""Run black code formatter in check mode."""
+
+import subprocess
+import sys
+import unittest
+
+import black
+
+from . import get_source_files, unittest_verbosity
+
+
+class BlackTestCase(unittest.TestCase):
+    """
+    This unittest class provides a test that runs the black code
+    formatter in check mode on the Python source code. The list of
+    source files is provided by the get_source_files() function.
+    """
+
+    def test_black(self) -> None:
+        """Test: Run black code formatter on Python source code."""
+        if int(black.__version__.split(".", 1)[0]) <= 20:
+            self.skipTest("black >= 21 needed")
+        cmd = ["black", "--check", "--diff"] + get_source_files()
+        if unittest_verbosity() >= 2:
+            sys.stderr.write(f"Running following command:\n{' '.join(cmd)}\n")
+        process = subprocess.run(cmd, capture_output=True, check=False, text=True)
+
+        if process.returncode == 1:  # pragma: no cover
+            self.fail(
+                f"black found code that needs reformatting:\n{process.stdout.strip()}"
+            )
+        if process.returncode != 0:  # pragma: no cover
+            self.fail(
+                f"black exited with code {process.returncode}:\n"
+                f"{process.stdout.strip()}"
+            )