Second fix for the TypeError bug introduced in 2.5 (#396)

pydantic_settings/sources.py

@@ -2115,13 +2115,16 @@ def read_env_file(
 def _annotation_is_complex(annotation: type[Any] | None, metadata: list[Any]) -> bool:
  # If the model is a root model, the root annotation should be used to
  # evaluate the complexity.
- if annotation is not None and inspect.isclass(annotation) and issubclass(annotation, RootModel):
- # In some rare cases (see test_root_model_as_field),
- # the root attribute is not available. For these cases, python 3.8 and 3.9
- # return 'RootModelRootType'.
- root_annotation = annotation.__annotations__.get('root', None)
- if root_annotation is not None and root_annotation != 'RootModelRootType':
- annotation = root_annotation
+ try:
+ if annotation is not None and issubclass(annotation, RootModel):
+ # In some rare cases (see test_root_model_as_field),
+ # the root attribute is not available. For these cases, python 3.8 and 3.9
+ # return 'RootModelRootType'.
+ root_annotation = annotation.__annotations__.get('root', None)
+ if root_annotation is not None and root_annotation != 'RootModelRootType':
+ annotation = root_annotation
+ except TypeError:
+ pass
 
  if any(isinstance(md, Json) for md in metadata): # type: ignore[misc]
  return False

tests/test_settings.py

@@ -4994,3 +4994,13 @@ class Settings(BaseSettings):
  s = Settings()
  assert s.POSTGRES_USER == 'postgres'
  assert s.model_dump() == {'POSTGRES_USER': 'postgres', 'postgres_name': 'name', 'postgres_user_2': 'postgres2'}
+
+
+@pytest.mark.skipif(sys.version_info < (3, 9), reason='requires python 3.9 or higher')
+def test_annotation_is_complex_root_model_check():
+ """Test for https://github.com/pydantic/pydantic-settings/issues/390"""
+
+ class Settings(BaseSettings):
+ foo: list[str] = []
+
+ Settings()