Added a couple of tests

runtype/dataclass.py

@@ -6,8 +6,8 @@
 from copy import copy
 import dataclasses
 import typing
-from typing import Union, Any, Callable, TypeVar, Dict, Optional, overload
-from typing import TYPE_CHECKING, ClassVar, Type
+from typing import Union, Callable, TypeVar, Dict, Optional, overload
+from typing import TYPE_CHECKING, Type, ForwardRef
 from abc import ABC, abstractmethod
 import inspect
 import types
@@ -16,12 +16,10 @@
 if TYPE_CHECKING:
     from typing_extensions import dataclass_transform
 else:
-
     def dataclass_transform(*a, **kw):
         return lambda f: f
 
 
-from .utils import ForwardRef
 from .common import CHECK_TYPES
 from .validation import TypeMismatchError, ensure_isa as default_ensure_isa
 from .pytypes import TypeCaster, SumType, NoneType, ATypeCaster, PythonType, type_caster

runtype/pytypes.py

@@ -15,20 +15,11 @@
 from datetime import datetime, date, time, timedelta
 from types import FrameType
 
-from .utils import ForwardRef
 from .base_types import DataType, Validator, TypeMismatchError, dp, Variance
 from . import base_types
 from . import datetime_parse
 
 
-if sys.version_info < (3, 9):
-    _orig_eval = ForwardRef._evaluate
-
-    def _forwardref_evaluate(self, glob, loc, _):
-        return _orig_eval(self, glob, loc)
-else:
-    _forwardref_evaluate = ForwardRef._evaluate
-
 try:
     import typing_extensions
 except ImportError:
@@ -526,10 +517,10 @@ def _to_canon(self, t):
         if isinstance(t, (base_types.Type, Validator)):
             return t
 
-        if isinstance(t, ForwardRef):
+        if isinstance(t, typing.ForwardRef):
             if self.frame is None:
                 raise RuntimeError("Cannot resolve ForwardRef: TypeCaster initialized without a frame")
-            t = _forwardref_evaluate(t, self.frame.f_globals, self.frame.f_locals, frozenset())
+            t = typing._eval_type(t, self.frame.f_globals, self.frame.f_locals)
 
         if isinstance(t, tuple):
             return SumType.create([to_canon(x) for x in t])

runtype/utils.py

@@ -1,10 +1,7 @@
 import inspect
-import sys
 import contextvars
 from contextlib import contextmanager
 
-from typing import ForwardRef as ForwardRef
-
 def get_func_signatures(typesystem, f):
     sig = inspect.signature(f)
     typesigs = []

tests/test_basic.py

@@ -241,6 +241,11 @@ def test_type_generic(self):
         assert issubclass(typing.Type[typing.List[int]], typing.Type[typing.Sequence[int]])
         assert not issubclass(typing.Type[typing.List[int]], typing.Type[typing.Sequence[str]])
 
+        assert issubclass(typing.Type[int], typing.Type[object])
+        assert issubclass(typing.Type[int], typing.Type[typing.Any])
+        assert not issubclass(typing.Type[object], typing.Type[int])
+        assert issubclass(typing.Type[typing.Any], typing.Type[int])
+
     def test_any(self):
         assert is_subtype(int, Any)
         assert is_subtype(Any, int)
@@ -863,6 +868,15 @@ class A:
         self.assertRaises(TypeError, A)
         self.assertRaises(TypeError, A, 2)
 
+    def test_self_reference(self):
+        @dataclass
+        class A:
+            items: List["A"]
+
+        a1 = A([])
+        a2 = A([a1])
+        self.assertRaises(TypeError, A, [1])
+
     def test_forward_references(self):
         @dataclass
         class A: