Refs #21275 -- Added more tests for @deconstructible decorator.

tests/utils_tests/deconstructible_classes.py

@@ -0,0 +1 @@
+from .test_deconstruct import DeconstructibleWithPathClass  # NOQA

tests/utils_tests/test_deconstruct.py

@@ -0,0 +1,68 @@
+from django.test import SimpleTestCase
+from django.utils.deconstruct import deconstructible
+from django.utils.version import get_docs_version
+
+
+@deconstructible()
+class DeconstructibleClass:
+    pass
+
+
+class DeconstructibleChildClass(DeconstructibleClass):
+    pass
+
+
+@deconstructible(
+    path='utils_tests.deconstructible_classes.DeconstructibleWithPathClass'
+)
+class DeconstructibleWithPathClass:
+    pass
+
+
+@deconstructible(
+    path='utils_tests.deconstructible_classes.DeconstructibleInvalidPathClass',
+)
+class DeconstructibleInvalidPathClass:
+    pass
+
+
+class DeconstructibleTests(SimpleTestCase):
+    def test_deconstruct(self):
+        obj = DeconstructibleClass('arg', key='value')
+        path, args, kwargs = obj.deconstruct()
+        self.assertEqual(path, 'utils_tests.test_deconstruct.DeconstructibleClass')
+        self.assertEqual(args, ('arg',))
+        self.assertEqual(kwargs, {'key': 'value'})
+
+    def test_deconstruct_with_path(self):
+        obj = DeconstructibleWithPathClass('arg', key='value')
+        path, args, kwargs = obj.deconstruct()
+        self.assertEqual(
+            path,
+            'utils_tests.deconstructible_classes.DeconstructibleWithPathClass',
+        )
+        self.assertEqual(args, ('arg',))
+        self.assertEqual(kwargs, {'key': 'value'})
+
+    def test_deconstruct_child(self):
+        obj = DeconstructibleChildClass('arg', key='value')
+        path, args, kwargs = obj.deconstruct()
+        self.assertEqual(path, 'utils_tests.test_deconstruct.DeconstructibleChildClass')
+        self.assertEqual(args, ('arg',))
+        self.assertEqual(kwargs, {'key': 'value'})
+
+    def test_invalid_path(self):
+        obj = DeconstructibleInvalidPathClass()
+        docs_version = get_docs_version()
+        msg = (
+            f'Could not find object DeconstructibleInvalidPathClass in '
+            f'utils_tests.deconstructible_classes.\n'
+            f'Please note that you cannot serialize things like inner '
+            f'classes. Please move the object into the main module body to '
+            f'use migrations.\n'
+            f'For more information, see '
+            f'https://docs.djangoproject.com/en/{docs_version}/topics/'
+            f'migrations/#serializing-values'
+        )
+        with self.assertRaisesMessage(ValueError, msg):
+            obj.deconstruct()