Clean up container instance and add tests

src/dependency_injector/containers.pyi

@@ -47,9 +47,9 @@ class Container:
     def reset_singletons(self) -> None: ...
     def resolve_provider_name(self, provider: Provider) -> str: ...
     @property
-    def parent_name(self) -> str: ...
+    def parent(self) -> Optional[ProviderParent]: ...
     @property
-    def parent(self) -> ProviderParent: ...
+    def parent_name(self) -> Optional[str]: ...
     def assign_parent(self, parent: ProviderParent) -> None: ...
     @overload
     def traverse(self, types: Optional[Iterable[Type[TT]]] = None) -> Iterator[TT]: ...

src/dependency_injector/containers.pyx

@@ -305,6 +305,14 @@ class DynamicContainer(Container):
         for provider in self.traverse(types=[providers.BaseSingleton]):
             provider.reset()
 
+    def resolve_provider_name(self, provider):
+        """Try to resolve provider name."""
+        for provider_name, container_provider in self.providers.items():
+            if container_provider is provider:
+                return provider_name
+        else:
+            raise errors.Error(f'Can not resolve name for provider "{provider}"')
+
     @property
     def parent_name(self):
         """Return parent name."""
@@ -320,15 +328,6 @@ class DynamicContainer(Container):
         """Assign parent."""
         self.parent = parent
 
-    def resolve_provider_name(self, provider):
-        """Try to resolve provider name."""
-        # TODO: add tests
-        for provider_name, container_provider in self.providers.items():
-            if container_provider is provider:
-                return provider_name
-        else:
-            raise errors.Error(f'Can not resolve name for provider "{provider}"')
-
 
 class DeclarativeContainerMetaClass(type):
     """Declarative inversion of control container meta class."""

tests/unit/containers/test_dynamic_py2_py3.py

@@ -336,6 +336,62 @@ class DeclarativeContainerInstanceTests(unittest.TestCase):
         self.assertIs(obj32, obj42)
         self.assertIs(obj33, obj43)
 
+    def test_assign_parent(self):
+        parent = providers.DependenciesContainer()
+        container = ContainerA()
+
+        container.assign_parent(parent)
+
+        self.assertIs(container.parent, parent)
+
+    def test_parent_name_declarative_parent(self):
+        container = ContainerA()
+        self.assertEqual(container.parent_name, 'ContainerA')
+
+    def test_parent_name(self):
+        container = ContainerA()
+        self.assertEqual(container.parent_name, 'ContainerA')
+
+    def test_parent_name_with_deep_parenting(self):
+        class Container2(containers.DeclarativeContainer):
+
+            name = providers.Container(ContainerA)
+
+        class Container1(containers.DeclarativeContainer):
+
+            container = providers.Container(Container2)
+
+        container = Container1()
+        self.assertEqual(container.container().name.parent_name, 'Container1.container.name')
+
+    def test_parent_name_is_none(self):
+        container = containers.DynamicContainer()
+        self.assertIsNone(container.parent_name)
+
+    def test_parent_deepcopy(self):
+        class Container(containers.DeclarativeContainer):
+            container = providers.Container(ContainerA)
+
+        container = Container()
+
+        copied = providers.deepcopy(container)
+
+        self.assertIs(container.container.parent, container)
+        self.assertIs(copied.container.parent, copied)
+
+        self.assertIsNot(container, copied)
+        self.assertIsNot(container.container, copied.container)
+        self.assertIsNot(container.container.parent, copied.container.parent)
+
+    def test_resolve_provider_name(self):
+        container = ContainerA()
+        self.assertEqual(container.resolve_provider_name(container.p11), 'p11')
+
+    def test_resolve_provider_name_no_provider(self):
+        container = ContainerA()
+        with self.assertRaises(errors.Error):
+            container.resolve_provider_name(providers.Provider())
+
 
 class SelfTests(unittest.TestCase):