Tests related to loading settings from a given file

doorstop/cli/tests/test_main.py

@@ -9,7 +9,7 @@
 
 from doorstop import settings
 from doorstop.cli import main
-from doorstop.cli.tests import SettingsTestCase
+from doorstop.cli.tests import FILES, SettingsTestCase
 
 
 class TestMain(SettingsTestCase):
@@ -84,3 +84,12 @@ def test_main(self):
             spec.loader.exec_module(runpy)
             # Assert
             self.assertIsNotNone(runpy)
+
+    @patch("doorstop.cli.commands.run", Mock())
+    def test_run_modified_settings_through_file(self):
+        """Verify --settings has override settings."""
+        main.main(args=["--settings", f"{FILES}/settings_modified.py"])
+        self.assertEqual(settings.MAX_LINE_LENGTH, 20)
+        # rollback to the original value to not impact an item test
+        settings.MAX_LINE_LENGTH = 79
+        self.assertEqual(settings.MAX_LINE_LENGTH, 79)

doorstop/core/tests/__init__.py

@@ -103,6 +103,15 @@ def set_items(self, items):
         self._items = items
 
 
+class MockSimpleDocumentExtensions(MockSimpleDocument):
+    """Mock Document class that enable extensions."""
+
+    def __init__(self, **kwargs):
+        super().__init__()
+        for k, v in kwargs.items():
+            self.extensions[k] = v
+
+
 class MockDocumentSkip(MockDocument):  # pylint: disable=W0223,R0902
     """Mock Document class that is always skipped in tree placement."""