Add support for type[strawberry.UNSET]

RELEASE.md

@@ -0,0 +1,3 @@
+Release type: minor
+
+Support for `type[strawberry.UNSET]` in addition to `strawberry.types.unset.UnsetType` for annotations.

strawberry/annotation.py

@@ -197,7 +197,9 @@ def create_optional(self, evaled_type: Any) -> StrawberryOptional:
         types = get_args(evaled_type)
         non_optional_types = tuple(
             filter(
-                lambda x: x is not type(None) and x is not type(UNSET),
+                lambda x: x is not type(None)
+                and x is not type(UNSET)
+                and x != type[UNSET],
                 types,
             )
         )

tests/types/resolving/test_optionals.py

@@ -28,6 +28,17 @@ def test_optional_with_unset():
     assert resolved == Optional[str]
 
 
+def test_optional_with_type_of_unset():
+    annotation = StrawberryAnnotation(Union[type[strawberry.UNSET], Optional[str]])
+    resolved = annotation.resolve()
+
+    assert isinstance(resolved, StrawberryOptional)
+    assert resolved.of_type is str
+
+    assert resolved == StrawberryOptional(of_type=str)
+    assert resolved == Optional[str]
+
+
 def test_optional_with_unset_as_union():
     annotation = StrawberryAnnotation(Union[UnsetType, None, str])
     resolved = annotation.resolve()