fix: allow async errors to bubble to AsyncIterable list items

Replicates graphql/graphql-js@84797fb

Author: Cito

src/graphql/execution/execute.py

@@ -1213,8 +1213,23 @@ async def complete_async_iterator_value(
                         async_payload_record,
                     )
                     if is_awaitable(completed_item):
+                        # noinspection PyShadowingNames
+                        async def catch_error(
+                            completed_item: Awaitable[Any], field_path: Path
+                        ) -> Any:
+                            try:
+                                return await completed_item
+                            except Exception as raw_error:
+                                error = located_error(
+                                    raw_error, field_nodes, field_path.as_list()
+                                )
+                                handle_field_error(error, item_type, errors)
+                                return None
+
+                        append_result(catch_error(completed_item, field_path))
                         append_awaitable(index)
-                    append_result(completed_item)
+                    else:
+                        append_result(completed_item)
                 except Exception as raw_error:
                     append_result(None)
                     error = located_error(raw_error, field_nodes, field_path.as_list())

tests/execution/test_lists.py

@@ -9,6 +9,7 @@
     GraphQLField,
     GraphQLFieldResolver,
     GraphQLList,
+    GraphQLNonNull,
     GraphQLObjectType,
     GraphQLResolveInfo,
     GraphQLSchema,
@@ -155,7 +156,11 @@ async def _list_field(
                         GraphQLList(
                             GraphQLObjectType(
                                 "ObjectWrapper",
-                                {"index": GraphQLField(GraphQLString, resolve=resolve)},
+                                {
+                                    "index": GraphQLField(
+                                        GraphQLNonNull(GraphQLString), resolve=resolve
+                                    )
+                                },
                             )
                         ),
                         resolve=_list_field,
@@ -274,7 +279,7 @@ async def resolve(data: _IndexData, info_: GraphQLResolveInfo) -> int:
             return index
 
         assert await _complete_object_lists(resolve) == (
-            {"listField": [{"index": "0"}, {"index": "1"}, {"index": None}]},
+            {"listField": [{"index": "0"}, {"index": "1"}, None]},
             [
                 {
                     "message": "bad",