build_client_schema: include standard type only if it is used

Replicates graphql/graphql-js@ff0afa2

Author: Cito

graphql/utilities/build_client_schema.py

@@ -312,7 +312,8 @@ def build_directive(directive_introspection: Dict) -> GraphQLDirective:
     for std_type_name, std_type in chain(
         specified_scalar_types.items(), introspection_types.items()
     ):
-        type_map[std_type_name] = std_type
+        if std_type_name in type_map:
+            type_map[std_type_name] = std_type
 
     # Get the root Query, Mutation, and Subscription types.
 

tests/utilities/test_build_client_schema.py

@@ -39,24 +39,12 @@ def cycle_introspection(sdl_string):
     # it should get a result identical to what was returned by the server
     second_introspection = introspection_from_schema(client_schema)
 
-    hack_to_remove_standard_types(second_introspection)
-    hack_to_remove_standard_types(initial_introspection)
-
     # If the client then runs the introspection query against the client-side
     # schema, it should get a result identical to what was returned by the server.
     assert initial_introspection == second_introspection
     return print_schema(client_schema)
 
 
-# Temporary hack to remove always presented standard types - should be removed in 15.0
-def hack_to_remove_standard_types(introspection):
-    introspection["__schema"]["types"] = [
-        type_
-        for type_ in introspection["__schema"]["types"]
-        if type_["name"] not in ("ID", "Float", "Int", "Boolean", "String")
-    ]
-
-
 def describe_type_system_build_schema_from_introspection():
     def builds_a_simple_schema():
         sdl = dedent(
@@ -139,6 +127,21 @@ def uses_built_in_scalars_when_possible():
         custom_scalar = schema.get_type("CustomScalar")
         assert client_schema.get_type("CustomScalar") is not custom_scalar
 
+    def include_standard_type_only_if_it_is_used():
+        schema = build_schema(
+            """
+            type Query {
+              foo: String
+            }
+            """
+        )
+        introspection = introspection_from_schema(schema)
+        client_schema = build_client_schema(introspection)
+
+        assert client_schema.get_type("Int") is None
+        assert client_schema.get_type("Float") is None
+        assert client_schema.get_type("ID") is None
+
     def builds_a_schema_with_a_recursive_type_reference():
         sdl = dedent(
             """
@@ -325,10 +328,8 @@ def builds_a_schema_with_an_enum():
 
         introspection = introspection_from_schema(schema)
         client_schema = build_client_schema(introspection)
-        second_introspection = introspection_from_schema(client_schema)
 
-        hack_to_remove_standard_types(second_introspection)
-        hack_to_remove_standard_types(introspection)
+        second_introspection = introspection_from_schema(client_schema)
         assert second_introspection == introspection
 
         client_food_enum = client_schema.get_type("Food")