fix: code quality issues (#406)

* Refactor unnecessary `else` / `elif` when `if` block has a `return` statement

* Remove unused imports

* Use literal syntax to create data structure

* revert "remove unused import"

src/dependency_injector/wiring.py

@@ -111,20 +111,19 @@ class ProvidersMap:
     ) -> Optional[providers.Provider]:
         if isinstance(provider, providers.Delegate):
             return self._resolve_delegate(provider)
-        elif isinstance(provider, (
+        if isinstance(provider, (
             providers.ProvidedInstance,
             providers.AttributeGetter,
             providers.ItemGetter,
             providers.MethodCaller,
         )):
             return self._resolve_provided_instance(provider)
-        elif isinstance(provider, providers.ConfigurationOption):
+        if isinstance(provider, providers.ConfigurationOption):
             return self._resolve_config_option(provider)
-        elif isinstance(provider, providers.TypedConfigurationOption):
+        if isinstance(provider, providers.TypedConfigurationOption):
             return self._resolve_config_option(provider.option, as_=provider.provides)
-        elif isinstance(provider, str):
+        if isinstance(provider, str):
             return self._resolve_string_id(provider, modifier)
-        else:
         return self._resolve_provider(provider)
 
     def _resolve_string_id(

tests/unit/providers/test_callables_py2_py3.py

@@ -69,7 +69,7 @@ class CallableTests(unittest.TestCase):
         provider = providers.Callable(_example) \
             .add_args(1, 2) \
             .set_args(3, 4)
-        self.assertEqual(provider.args, tuple([3, 4]))
+        self.assertEqual(provider.args, (3, 4))
 
     def test_set_kwargs(self):
         provider = providers.Callable(_example) \

tests/unit/providers/test_coroutines_py35.py

@@ -87,7 +87,7 @@ class CoroutineTests(AsyncTestCase):
         provider = providers.Coroutine(_example) \
             .add_args(1, 2) \
             .set_args(3, 4)
-        self.assertEqual(provider.args, tuple([3, 4]))
+        self.assertEqual(provider.args, (3, 4))
 
     def test_set_kwargs(self):
         provider = providers.Coroutine(_example) \

tests/unit/providers/test_factories_py2_py3.py

@@ -228,7 +228,7 @@ class FactoryTests(unittest.TestCase):
         provider = providers.Factory(Example) \
             .add_args(1, 2) \
             .set_args(3, 4)
-        self.assertEqual(provider.args, tuple([3, 4]))
+        self.assertEqual(provider.args, (3, 4))
 
     def test_set_kwargs(self):
         provider = providers.Factory(Example) \

tests/unit/providers/test_list_py2_py3.py

@@ -42,7 +42,7 @@ class ListTests(unittest.TestCase):
         provider = providers.List() \
             .add_args(1, 2) \
             .set_args(3, 4)
-        self.assertEqual(provider.args, tuple([3, 4]))
+        self.assertEqual(provider.args, (3, 4))
 
     def test_clear_args(self):
         provider = providers.List() \

tests/unit/providers/test_resource_py35.py

@@ -203,7 +203,7 @@ class ResourceTests(unittest.TestCase):
         provider = providers.Resource(init_fn) \
             .add_args(1, 2) \
             .set_args(3, 4)
-        self.assertEqual(provider.args, tuple([3, 4]))
+        self.assertEqual(provider.args, (3, 4))
 
     def test_clear_args(self):
         provider = providers.Resource(init_fn) \

tests/unit/providers/test_singletons_py2_py3.py

@@ -190,7 +190,7 @@ class _BaseSingletonTestCase(object):
         provider = self.singleton_cls(Example) \
             .add_args(1, 2) \
             .set_args(3, 4)
-        self.assertEqual(provider.args, tuple([3, 4]))
+        self.assertEqual(provider.args, (3, 4))
 
     def test_set_kwargs(self):
         provider = self.singleton_cls(Example) \

tests/unit/wiring/test_wiring_string_ids_py36.py

@@ -1,15 +1,10 @@
-import contextlib
 from decimal import Decimal
-import importlib
 import unittest
 
 from dependency_injector.wiring import (
     wire,
     Provide,
-    Closing,
-    register_loader_containers,
-    unregister_loader_containers,
-)
+    Closing)
 from dependency_injector import errors
 
 # Runtime import to avoid syntax errors in samples on Python < 3.5