Return ABCMeta class for resource classes and add tests for abc

Author: rmk135

src/dependency_injector/resources.py

@@ -7,7 +7,7 @@
 T = TypeVar('T')
 
 
-class Resource(Generic[T]):
+class Resource(Generic[T], metaclass=abc.ABCMeta):
 
  @abc.abstractmethod
  def init(self, *args, **kwargs) -> T:
@@ -18,7 +18,7 @@ def shutdown(self, resource: T) -> None:
  ...
 
 
-class AsyncResource(Generic[T]):
+class AsyncResource(Generic[T], metaclass=abc.ABCMeta):
 
  @abc.abstractmethod
  async def init(self, *args, **kwargs) -> T:

tests/unit/providers/test_resource_py35.py

@@ -145,6 +145,44 @@ def shutdown(self, _):
  self.assertEqual(TestResource.init_counter, 2)
  self.assertEqual(TestResource.shutdown_counter, 2)
 
+ def test_init_class_generic_typing(self):
+ # See issue: https://github.com/ets-labs/python-dependency-injector/issues/488
+ class TestDependency:
+ ...
+
+ class TestResource(resources.Resource[TestDependency]):
+ def init(self, *args: Any, **kwargs: Any) -> TestDependency:
+ return TestDependency()
+
+ def shutdown(self, resource: TestDependency) -> None: ...
+
+ self.assertTrue(issubclass(TestResource, resources.Resource))
+
+ def test_init_class_abc_definition_is_required(self):
+ class TestResource(resources.Resource):
+ ...
+
+ with self.assertRaises(TypeError) as context:
+ TestResource()
+
+ self.assertEqual(
+ "Can't instantiate abstract class TestResource with abstract methods init, shutdown",
+ str(context.exception),
+ )
+
+ def test_init_class_abc_shutdown_definition_is_required(self):
+ class TestResource(resources.Resource):
+ def init(self):
+ ...
+
+ with self.assertRaises(TypeError) as context:
+ TestResource()
+
+ self.assertEqual(
+ "Can't instantiate abstract class TestResource with abstract method shutdown",
+ str(context.exception),
+ )
+
  def test_init_not_callable(self):
  provider = providers.Resource(1)
  with self.assertRaises(errors.Error):
@@ -449,6 +487,44 @@ async def shutdown(self, resource_):
  self.assertEqual(TestResource.init_counter, 2)
  self.assertEqual(TestResource.shutdown_counter, 2)
 
+ def test_init_async_class_generic_typing(self):
+ # See issue: https://github.com/ets-labs/python-dependency-injector/issues/488
+ class TestDependency:
+ ...
+
+ class TestAsyncResource(resources.AsyncResource[TestDependency]):
+ async def init(self, *args: Any, **kwargs: Any) -> TestDependency:
+ return TestDependency()
+
+ async def shutdown(self, resource: TestDependency) -> None: ...
+
+ self.assertTrue(issubclass(TestAsyncResource, resources.AsyncResource))
+
+ def test_init_async_class_abc_definition_is_required(self):
+ class TestAsyncResource(resources.AsyncResource):
+ ...
+
+ with self.assertRaises(TypeError) as context:
+ TestAsyncResource()
+
+ self.assertEqual(
+ "Can't instantiate abstract class TestAsyncResource with abstract methods init, shutdown",
+ str(context.exception),
+ )
+
+ def test_init_async_class_abc_shutdown_definition_is_required(self):
+ class TestAsyncResource(resources.AsyncResource):
+ async def init(self):
+ ...
+
+ with self.assertRaises(TypeError) as context:
+ TestAsyncResource()
+
+ self.assertEqual(
+ "Can't instantiate abstract class TestAsyncResource with abstract method shutdown",
+ str(context.exception),
+ )
+
  def test_init_with_error(self):
  async def _init():
  raise RuntimeError()
@@ -603,31 +679,3 @@ async def _init():
 
  self.assertIs(result2, resource)
  self.assertEqual(_init.counter, 1)
-
-
-class ResourceTypingTest(unittest.TestCase):
- # See issue: https://github.com/ets-labs/python-dependency-injector/issues/488
-
- def test_sync_generic_type(self):
- class MyDependency:
- ...
-
- class MyResource(resources.Resource[MyDependency]):
- def init(self, *args: Any, **kwargs: Any) -> MyDependency:
- return MyDependency()
-
- def shutdown(self, resource: MyDependency) -> None: ...
-
- self.assertTrue(issubclass(MyResource, resources.Resource))
-
- def test_async_generic_type(self):
- class MyDependency:
- ...
-
- class MyAsyncResource(resources.AsyncResource[MyDependency]):
- async def init(self, *args: Any, **kwargs: Any) -> MyDependency:
- return MyDependency()
-
- async def shutdown(self, resource: MyDependency) -> None: ...
-
- self.assertTrue(issubclass(MyAsyncResource, resources.AsyncResource))