Cherry pick #283

apischema/typing.py

@@ -158,27 +158,30 @@ def resolve_type_hints(obj: Any) -> Dict[str, Any]:
 
     `obj` can also be a parametrized generic class."""
     origin_or_obj = get_origin(obj) or obj
-    hints = get_type_hints(origin_or_obj, include_extras=True)
     if isinstance(origin_or_obj, type):
+        hints = {}
         for base in reversed(generic_mro(obj)):
-            base_origin = get_origin(base)
-            if base_origin is not None and getattr(base_origin, "__parameters__", ()):  # type: ignore
-                substitution = dict(zip(base_origin.__parameters__, get_args(base)))
-                base_annotations = getattr(base_origin, "__dict__", {}).get(
-                    "__annotations__", {}
-                )
-                for name, hint in get_type_hints(base_origin).items():
-                    if name not in base_annotations:
-                        continue
-                    if isinstance(hint, TypeVar):
-                        hints[name] = substitution.get(hint, hint)
-                    elif getattr(hint, "__parameters__", ()):
-                        hints[name] = hint[
-                            tuple(substitution.get(p, p) for p in hint.__parameters__)
-                        ]
-                    else:
-                        hints[name] = hint
-    return hints
+            base_origin = get_origin(base) or base
+            base_annotations = getattr(base_origin, "__dict__", {}).get(
+                "__annotations__", {}
+            )
+            substitution = dict(
+                zip(getattr(base_origin, "__parameters__", ()), get_args(base))
+            )
+            for name, hint in get_type_hints(base_origin, include_extras=True).items():
+                if name not in base_annotations:
+                    continue
+                if isinstance(hint, TypeVar):
+                    hints[name] = substitution.get(hint, hint)
+                elif getattr(hint, "__parameters__", ()):
+                    hints[name] = (Union if is_union(hint) else hint)[
+                        tuple(substitution.get(p, p) for p in hint.__parameters__)
+                    ]
+                else:
+                    hints[name] = hint
+        return hints
+    else:
+        return get_type_hints(obj, include_extras=True)
 
 
 _T = TypeVar("_T")

apischema/utils.py

@@ -171,7 +171,9 @@ def substitute_type_vars(tp: AnyType, substitution: Mapping[TV, AnyType]) -> Any
         except KeyError:
             return Union[tp.__constraints__] if tp.__constraints__ else Any
     elif getattr(tp, "__parameters__", ()):
-        return tp[tuple(substitution.get(p, p) for p in tp.__parameters__)]
+        return (Union if is_union(tp) else tp)[
+            tuple(substitution.get(p, p) for p in tp.__parameters__)
+        ]
     else:
         return tp
 

setup.py

@@ -5,7 +5,7 @@
 
 setup(
     name="apischema",
-    version="0.16.5",
+    version="0.16.6",
     url="https://github.com/wyfo/apischema",
     author="Joseph Perez",
     author_email="joperez@hotmail.fr",

tests/integration/test_unsupported_union_member.py

@@ -1,5 +1,5 @@
 from dataclasses import dataclass
-from typing import Annotated, Union
+from typing import Annotated, Union  # type: ignore
 
 from pytest import raises
 

tests/test_typing.py

@@ -9,6 +9,7 @@
     required_keys,
     resolve_type_hints,
 )
+from apischema.typing import Annotated
 
 T = TypeVar("T")
 U = TypeVar("U")
@@ -28,7 +29,7 @@ class C(B[str]):
 
 
 class D(C):
-    pass
+    d: Annotated[int, ""]
 
 
 test_cases = [
@@ -39,7 +40,11 @@ class D(C):
     (B[U], [B[U], A[int, U]], {"t": int, "u": U, "v": U}),
     (B[str], [B[str], A[int, str]], {"t": int, "u": str, "v": str}),
     (C, [C, B[str], A[int, str]], {"t": int, "u": str, "v": str}),
-    (D, [D, C, B[str], A[int, str]], {"t": int, "u": str, "v": str}),
+    (
+        D,
+        [D, C, B[str], A[int, str]],
+        {"t": int, "u": str, "v": str, "d": Annotated[int, ""]},
+    ),
 ]