Fix issue with self-referencing dataclass (#3713)

* Fix issue with self-referencing dataclass

* Fix mypy issue

changes/3675-uriyyo.md

@@ -0,0 +1 @@
+Fix issue with self-referencing dataclass

pydantic/dataclasses.py

@@ -184,7 +184,12 @@ def _process_class(
 
     validators = gather_all_validators(cls)
     cls.__pydantic_model__ = create_model(
-        cls.__name__, __config__=config, __module__=_cls.__module__, __validators__=validators, **field_definitions
+        cls.__name__,
+        __config__=config,
+        __module__=_cls.__module__,
+        __validators__=validators,
+        __cls_kwargs__={'__resolve_forward_refs__': False},
+        **field_definitions,
     )
 
     cls.__initialised__ = False
@@ -196,6 +201,8 @@ def _process_class(
     if cls.__pydantic_model__.__config__.validate_assignment and not frozen:
         cls.__setattr__ = setattr_validate_assignment  # type: ignore[assignment]
 
+    cls.__pydantic_model__.__try_update_forward_refs__(**{cls.__name__: cls})
+
     return cls
 
 

pydantic/generics.py

@@ -98,6 +98,7 @@ def __class_getitem__(cls: Type[GenericModelT], params: Union[Type[Any], Tuple[T
                 __base__=(cls,) + tuple(cls.__parameterized_bases__(typevars_map)),
                 __config__=None,
                 __validators__=validators,
+                __cls_kwargs__=None,
                 **fields,
             ),
         )

pydantic/main.py

@@ -154,6 +154,7 @@ def __new__(mcs, name, bases, namespace, **kwargs):  # noqa C901
                 class_vars.update(base.__class_vars__)
                 hash_func = base.__hash__
 
+        resolve_forward_refs = kwargs.pop('__resolve_forward_refs__', True)
         allowed_config_kwargs: SetStr = {
             key
             for key in dir(config)
@@ -289,7 +290,8 @@ def is_untouched(v: Any) -> bool:
         cls = super().__new__(mcs, name, bases, new_namespace, **kwargs)
         # set __signature__ attr only for model class, but not for its instances
         cls.__signature__ = ClassAttribute('__signature__', generate_model_signature(cls.__init__, fields, config))
-        cls.__try_update_forward_refs__()
+        if resolve_forward_refs:
+            cls.__try_update_forward_refs__()
 
         return cls
 
@@ -765,12 +767,12 @@ def _get_value(
             return v
 
     @classmethod
-    def __try_update_forward_refs__(cls) -> None:
+    def __try_update_forward_refs__(cls, **localns: Any) -> None:
         """
         Same as update_forward_refs but will not raise exception
         when forward references are not defined.
         """
-        update_model_forward_refs(cls, cls.__fields__.values(), cls.__config__.json_encoders, {}, (NameError,))
+        update_model_forward_refs(cls, cls.__fields__.values(), cls.__config__.json_encoders, localns, (NameError,))
 
     @classmethod
     def update_forward_refs(cls, **localns: Any) -> None:
@@ -892,6 +894,7 @@ def create_model(
     __base__: None = None,
     __module__: str = __name__,
     __validators__: Dict[str, 'AnyClassMethod'] = None,
+    __cls_kwargs__: Dict[str, Any] = None,
     **field_definitions: Any,
 ) -> Type['BaseModel']:
     ...
@@ -905,6 +908,7 @@ def create_model(
     __base__: Union[Type['Model'], Tuple[Type['Model'], ...]],
     __module__: str = __name__,
     __validators__: Dict[str, 'AnyClassMethod'] = None,
+    __cls_kwargs__: Dict[str, Any] = None,
     **field_definitions: Any,
 ) -> Type['Model']:
     ...
@@ -917,6 +921,7 @@ def create_model(
     __base__: Union[None, Type['Model'], Tuple[Type['Model'], ...]] = None,
     __module__: str = __name__,
     __validators__: Dict[str, 'AnyClassMethod'] = None,
+    __cls_kwargs__: Dict[str, Any] = None,
     **field_definitions: Any,
 ) -> Type['Model']:
     """
@@ -926,6 +931,7 @@ def create_model(
     :param __base__: base class for the new model to inherit from
     :param __module__: module of the created model
     :param __validators__: a dict of method names and @validator class methods
+    :param __cls_kwargs__: a dict for class creation
     :param field_definitions: fields of the model (or extra fields if a base is supplied)
         in the format `<name>=(<type>, <default default>)` or `<name>=<default value>, e.g.
         `foobar=(str, ...)` or `foobar=123`, or, for complex use-cases, in the format
@@ -940,6 +946,8 @@ def create_model(
     else:
         __base__ = (cast(Type['Model'], BaseModel),)
 
+    __cls_kwargs__ = __cls_kwargs__ or {}
+
     fields = {}
     annotations = {}
 
@@ -969,7 +977,7 @@ def create_model(
     if __config__:
         namespace['Config'] = inherit_config(__config__, BaseConfig)
 
-    return type(__model_name, __base__, namespace)
+    return type(__model_name, __base__, namespace, **__cls_kwargs__)
 
 
 _missing = object()

tests/test_dataclasses.py

@@ -989,3 +989,11 @@ def __new__(cls, *args, **kwargs):
         instance = cls(a=test_string)
         assert instance._special_property == 1
         assert instance.a == test_string
+
+
+def test_self_reference_dataclass():
+    @pydantic.dataclasses.dataclass
+    class MyDataclass:
+        self_reference: 'MyDataclass'
+
+    assert MyDataclass.__pydantic_model__.__fields__['self_reference'].type_ is MyDataclass