Support typing_extensions.Any (#490)

* Support `typing_extensions.Any`

* Add PR link

Author: Tinche

HISTORY.md

@@ -40,6 +40,8 @@ Our backwards-compatibility policy can be found [here](https://github.com/python
   ([#450](https://github.com/python-attrs/cattrs/pull/450))
 - `typing_extensions.Literal` is now automatically structured, just like `typing.Literal`.
   ([#460](https://github.com/python-attrs/cattrs/issues/460) [#467](https://github.com/python-attrs/cattrs/pull/467))
+- `typing_extensions.Any` is now supported and handled like `typing.Any`.
+  ([#488](https://github.com/python-attrs/cattrs/issues/488) [#490](https://github.com/python-attrs/cattrs/pull/490))
 - [PEP 695](https://peps.python.org/pep-0695/) generics are now tested.
   ([#452](https://github.com/python-attrs/cattrs/pull/452))
 - Imports are now sorted using Ruff.

docs/defaulthooks.md

@@ -469,6 +469,10 @@ When unstructuring, `typing.Any` will make the value be unstructured according t
 Previously, the unstructuring rules for `Any` were underspecified, leading to inconsistent behavior.
 ```
 
+```{versionchanged} 24.1.0
+`typing_extensions.Any` is now also supported.
+```
+
 ### `typing.Literal`
 
 When structuring, [PEP 586](https://peps.python.org/pep-0586/) literals are validated to be in the allowed set of values.

src/cattrs/_compat.py

@@ -35,6 +35,7 @@
 from attrs import fields_dict as attrs_fields_dict
 
 __all__ = [
+    "ANIES",
     "adapted_fields",
     "fields_dict",
     "ExceptionGroup",
@@ -77,6 +78,15 @@
 except ImportError:  # pragma: no cover
     pass
 
+# On some Python versions, `typing_extensions.Any` is different than
+# `typing.Any`.
+try:
+    from typing_extensions import Any as teAny
+
+    ANIES = frozenset([Any, teAny])
+except ImportError:  # pragma: no cover
+    ANIES = frozenset([Any])
+
 NoneType = type(None)
 
 

src/cattrs/converters.py

@@ -11,6 +11,7 @@
 from attrs import has as attrs_has
 
 from ._compat import (
+    ANIES,
     FrozenSetSubscriptable,
     Mapping,
     MutableMapping,
@@ -171,7 +172,7 @@ def __init__(
                 (lambda t: issubclass(t, Enum), self._unstructure_enum),
                 (has, self._unstructure_attrs),
                 (is_union_type, self._unstructure_union),
-                (lambda t: t is Any, self.unstructure),
+                (lambda t: t in ANIES, self.unstructure),
             ]
         )
 
@@ -181,7 +182,10 @@ def __init__(
         self._structure_func = MultiStrategyDispatch(structure_fallback_factory)
         self._structure_func.register_func_list(
             [
-                (lambda cl: cl is Any or cl is Optional or cl is None, lambda v, _: v),
+                (
+                    lambda cl: cl in ANIES or cl is Optional or cl is None,
+                    lambda v, _: v,
+                ),
                 (is_generic_attrs, self._gen_structure_generic, True),
                 (lambda t: get_newtype_base(t) is not None, self._structure_newtype),
                 (is_type_alias, self._find_type_alias_structure_hook, True),
@@ -545,7 +549,7 @@ def structure_attrs_fromdict(self, obj: Mapping[str, Any], cl: type[T]) -> T:
 
     def _structure_list(self, obj: Iterable[T], cl: Any) -> list[T]:
         """Convert an iterable to a potentially generic list."""
-        if is_bare(cl) or cl.__args__[0] is Any:
+        if is_bare(cl) or cl.__args__[0] in ANIES:
             res = list(obj)
         else:
             elem_type = cl.__args__[0]
@@ -575,7 +579,7 @@ def _structure_list(self, obj: Iterable[T], cl: Any) -> list[T]:
 
     def _structure_deque(self, obj: Iterable[T], cl: Any) -> deque[T]:
         """Convert an iterable to a potentially generic deque."""
-        if is_bare(cl) or cl.__args__[0] is Any:
+        if is_bare(cl) or cl.__args__[0] in ANIES:
             res = deque(e for e in obj)
         else:
             elem_type = cl.__args__[0]
@@ -607,7 +611,7 @@ def _structure_set(
         self, obj: Iterable[T], cl: Any, structure_to: type = set
     ) -> Set[T]:
         """Convert an iterable into a potentially generic set."""
-        if is_bare(cl) or cl.__args__[0] is Any:
+        if is_bare(cl) or cl.__args__[0] in ANIES:
             return structure_to(obj)
         elem_type = cl.__args__[0]
         handler = self._structure_func.dispatch(elem_type)
@@ -646,10 +650,10 @@ def _structure_dict(self, obj: Mapping[T, V], cl: Any) -> dict[T, V]:
         if is_bare(cl) or cl.__args__ == (Any, Any):
             return dict(obj)
         key_type, val_type = cl.__args__
-        if key_type is Any:
+        if key_type in ANIES:
             val_conv = self._structure_func.dispatch(val_type)
             return {k: val_conv(v, val_type) for k, v in obj.items()}
-        if val_type is Any:
+        if val_type in ANIES:
             key_conv = self._structure_func.dispatch(key_type)
             return {key_conv(k, key_type): v for k, v in obj.items()}
         key_conv = self._structure_func.dispatch(key_type)
@@ -673,7 +677,7 @@ def _structure_tuple(self, obj: Any, tup: type[T]) -> T:
         """Deal with structuring into a tuple."""
         tup_params = None if tup in (Tuple, tuple) else tup.__args__
         has_ellipsis = tup_params and tup_params[-1] is Ellipsis
-        if tup_params is None or (has_ellipsis and tup_params[0] is Any):
+        if tup_params is None or (has_ellipsis and tup_params[0] in ANIES):
             # Just a Tuple. (No generic information.)
             return tuple(obj)
         if has_ellipsis:

src/cattrs/gen/__init__.py

@@ -6,6 +6,7 @@
 from attrs import NOTHING, Factory, resolve_types
 
 from .._compat import (
+    ANIES,
     TypeAlias,
     adapted_fields,
     get_args,
@@ -831,7 +832,7 @@ def make_mapping_structure_fn(
                 (key_type,) = args
                 val_type = Any
 
-        is_bare_dict = val_type is Any and key_type is Any
+        is_bare_dict = val_type in ANIES and key_type in ANIES
         if not is_bare_dict:
             # We can do the dispatch here and now.
             key_handler = converter.get_structure_hook(key_type, cache_result=False)

tests/test_any.py

@@ -2,6 +2,7 @@
 from typing import Any, Dict, Optional
 
 from attrs import define
+from typing_extensions import Any as ExtendedAny
 
 
 @define
@@ -24,3 +25,12 @@ def test_unstructure_optional_any(converter):
     """Unstructuring `Optional[Any]` should use the runtime value."""
 
     assert converter.unstructure(A(), Optional[Any]) == {}
+
+
+def test_extended_any(converter):
+    """`typing_extensions.Any` works."""
+
+    assert converter.unstructure(A(), unstructure_as=ExtendedAny) == {}
+
+    d = {}
+    assert converter.structure(d, ExtendedAny) is d