Fix coverage

.coveragerc

@@ -3,6 +3,7 @@ source = constance
 branch = 1
 omit =
     */pytest.py
+    */tests/*
 
 [report]
 omit = *tests*,*migrations*,.tox/*,setup.py,*settings.py

constance/migrations/0003_drop_pickle.py

@@ -16,7 +16,7 @@ def import_module_attr(path):
     return getattr(import_module(package), module)
 
 
-def migrate_pickled_data(apps, schema_editor) -> None:
+def migrate_pickled_data(apps, schema_editor) -> None:  # pragma: no cover
     Constance = apps.get_model('constance', 'Constance')
 
     for constance in Constance.objects.exclude(value=None):

tests/test_codecs.py

@@ -52,6 +52,12 @@ def test_serializes_and_deserializes_default_types(self):
         ):
             self.assertEqual(t, loads(dumps(t)))
 
+    def test_invalid_deserialization(self):
+        with self.assertRaises(ValueError):
+            loads('THIS_IS_NOT_RIGHT')
+        with self.assertRaises(ValueError):
+            loads('{"__type__": "not_registred", "__value__": "test"}')
+
     def test_handles_unknown_type(self):
         class UnknownType:
             pass
@@ -73,6 +79,8 @@ def __init__(self, value):
         self.assertEqual(deserialized_data.value, 'test')
 
     def test_register_known_type(self):
+        with self.assertRaises(ValueError):
+            register_type(int, '', lambda o: o.value, lambda o: int(o))
         with self.assertRaises(ValueError):
             register_type(int, 'default', lambda o: o.value, lambda o: int(o))
         register_type(int, 'new_custom_type', lambda o: o.value, lambda o: int(o))