Fix nullable lists of non-scalars

strawberry/codegen/query_codegen.py

@@ -648,17 +648,19 @@ def _unwrap_type(
         wrapper = None
 
         if isinstance(type_, StrawberryOptional):
-            type_, wrapper = self._unwrap_type(type_.of_type)
+            type_, previous_wrapper = self._unwrap_type(type_.of_type)
             wrapper = (
                 GraphQLOptional
-                if wrapper is None
-                else lambda t: GraphQLOptional(wrapper(t))  # type: ignore[misc]
+                if previous_wrapper is None
+                else lambda t: GraphQLOptional(previous_wrapper(t))  # type: ignore[misc]
             )
 
         elif isinstance(type_, StrawberryList):
-            type_, wrapper = self._unwrap_type(type_.of_type)
+            type_, previous_wrapper = self._unwrap_type(type_.of_type)
             wrapper = (
-                GraphQLList if wrapper is None else lambda t: GraphQLList(wrapper(t))
+                GraphQLList
+                if previous_wrapper is None
+                else lambda t: GraphQLList(previous_wrapper(t))
             )
 
         elif isinstance(type_, LazyType):

tests/codegen/conftest.py

@@ -101,6 +101,7 @@ class Query:
     person: Person
     optional_person: Optional[Person]
     list_of_people: List[Person]
+    optional_list_of_people: Optional[List[Person]]
     enum: Color
     json: JSON
     union: PersonOrAnimal

tests/codegen/queries/optional_list_of_people.graphql

@@ -0,0 +1,6 @@
+query OptionalListOfPeople {
+  optionalListOfPeople {
+    name
+    age
+  }
+}

tests/codegen/snapshots/python/optional_list_of_people.py

@@ -0,0 +1,8 @@
+from typing import List, Optional
+
+class OptionalListOfPeopleResultOptionalListOfPeople:
+    name: str
+    age: int
+
+class OptionalListOfPeopleResult:
+    optional_list_of_people: Optional[List[OptionalListOfPeopleResultOptionalListOfPeople]]

tests/codegen/snapshots/typescript/optional_list_of_people.ts

@@ -0,0 +1,8 @@
+type OptionalListOfPeopleResultOptionalListOfPeople = {
+    name: string
+    age: number
+}
+
+type OptionalListOfPeopleResult = {
+    optional_list_of_people: OptionalListOfPeopleResultOptionalListOfPeople[] | undefined
+}