build/extend_schema: improve test coverage

Replicates graphql/graphql-js@fd0a3aa

Author: Cito

README.md

@@ -16,7 +16,7 @@ The current stable version 3.0.1 of GraphQL-core is up-to-date
 with GraphQL.js version 14.5.8.
 
 All parts of the API are covered by an extensive test suite
-of currently 2038 unit tests.
+of currently 2044 unit tests.
 
 
 ## Documentation

src/graphql/utilities/extend_schema.py

@@ -1,5 +1,5 @@
 from collections import defaultdict
-from typing import Any, Dict, List, Optional, Union, cast
+from typing import Any, Dict, List, Optional, cast
 
 from ..language import (
     DirectiveDefinitionNode,
@@ -69,7 +69,7 @@ def extend_schema(
     assert_schema(schema)
 
     if not isinstance(document_ast, DocumentNode):
-        "Must provide valid Document AST."
+        raise TypeError("Must provide valid Document AST.")
 
     if not (assume_valid or assume_valid_sdl):
         from ..validation.validate import assert_valid_sdl_extension
@@ -316,11 +316,6 @@ def resolve_type(type_name: str) -> GraphQLNamedType:
         type_map[existing_type_name] = extend_named_type(existing_type)
 
     # Get the extended root operation types.
-    schema_types: List[Union[SchemaDefinitionNode, SchemaExtensionNode]] = []
-    if schema_def:
-        schema_types.append(schema_def)
-    if schema_extensions:
-        schema_types.extend(schema_extensions)
     operation_types: Dict[OperationType, GraphQLObjectType] = {}
     if schema.query_type:
         operation_types[OperationType.QUERY] = cast(
@@ -334,10 +329,11 @@ def resolve_type(type_name: str) -> GraphQLNamedType:
         operation_types[OperationType.SUBSCRIPTION] = cast(
             GraphQLObjectType, replace_named_type(schema.subscription_type)
         )
-    operation_types.update(
-        # Then, incorporate schema definition and all schema extensions.
-        ast_builder.get_operation_types(schema_types)
-    )
+    # Then, incorporate schema definition and all schema extensions.
+    if schema_def:
+        operation_types.update(ast_builder.get_operation_types([schema_def]))
+    if schema_extensions:
+        operation_types.update(ast_builder.get_operation_types(schema_extensions))
 
     # Then produce and return a Schema with these types.
     get_operation = operation_types.get

tests/utilities/test_build_ast_schema.py

@@ -91,6 +91,18 @@ def add(self, _info, x, y):
             None,
         )
 
+    def ignores_non_type_system_definitions():
+        sdl = """
+            type Query {
+              str: String
+            }
+
+            fragment SomeFragment on Query {
+              str
+            }
+            """
+        build_schema(sdl)
+
     def empty_type():
         sdl = dedent(
             """
@@ -428,9 +440,8 @@ def can_build_recursive_union():
                 }
                 """
             )
-        msg = str(exc_info.value)
         assert (
-            msg == "Hello types must be specified"
+            str(exc_info.value) == "Hello types must be specified"
             " as a collection of GraphQLObjectType instances."
         )
 
@@ -898,8 +909,7 @@ def rejects_invalid_sdl():
             """
         with raises(TypeError) as exc_info:
             build_schema(sdl)
-        msg = str(exc_info.value)
-        assert msg == "Unknown directive '@unknown'."
+        assert str(exc_info.value) == "Unknown directive '@unknown'."
 
     def allows_to_disable_sdl_validation():
         sdl = """
@@ -909,3 +919,21 @@ def allows_to_disable_sdl_validation():
             """
         build_schema(sdl, assume_valid=True)
         build_schema(sdl, assume_valid_sdl=True)
+
+    def throws_on_unknown_types():
+        sdl = """
+            type Query {
+              unknown: UnknownType
+            }
+            """
+        with raises(TypeError) as exc_info:
+            build_schema(sdl, assume_valid_sdl=True)
+        assert str(exc_info.value).endswith("'UnknownType' not found in document.")
+
+    def rejects_invalid_ast():
+        with raises(TypeError) as exc_info:
+            build_ast_schema(None)  # type: ignore
+        assert str(exc_info.value) == "Must provide valid Document AST."
+        with raises(TypeError) as exc_info:
+            build_ast_schema({})  # type: ignore
+        assert str(exc_info.value) == "Must provide valid Document AST."

tests/utilities/test_extend_schema.py

@@ -1189,8 +1189,7 @@ def rejects_invalid_sdl():
 
         with raises(TypeError) as exc_info:
             extend_schema(schema, extend_ast)
-        msg = str(exc_info.value)
-        assert msg == "Unknown directive '@unknown'."
+        assert str(exc_info.value) == "Unknown directive '@unknown'."
 
     def allows_to_disable_sdl_validation():
         schema = GraphQLSchema()
@@ -1199,6 +1198,30 @@ def allows_to_disable_sdl_validation():
         extend_schema(schema, extend_ast, assume_valid=True)
         extend_schema(schema, extend_ast, assume_valid_sdl=True)
 
+    def throws_on_unknown_types():
+        schema = GraphQLSchema()
+        ast = parse(
+            """
+            type Query {
+              unknown: UnknownType
+            }
+            """
+        )
+        with raises(TypeError) as exc_info:
+            extend_schema(schema, ast, assume_valid_sdl=True)
+        assert str(exc_info.value).endswith("Unknown type: 'UnknownType'.")
+
+    def rejects_invalid_ast():
+        schema = GraphQLSchema()
+
+        with raises(TypeError) as exc_info:
+            extend_schema(schema, None)  # type: ignore
+        assert str(exc_info.value) == "Must provide valid Document AST."
+
+        with raises(TypeError) as exc_info:
+            extend_schema(schema, {})  # type: ignore
+        assert str(exc_info.value) == "Must provide valid Document AST."
+
     def does_not_allow_replacing_a_default_directive():
         schema = GraphQLSchema()
         extend_ast = parse(
@@ -1289,6 +1312,23 @@ def adds_new_root_types_via_schema_extension():
             assert mutation_type.name == "MutationRoot"
             assert print_extension_nodes(extended_schema) == extension_sdl
 
+        def adds_directive_via_schema_extension():
+            schema = build_schema(
+                """
+                type Query
+
+                directive @foo on SCHEMA
+                """
+            )
+            extension_sdl = dedent(
+                """
+                extend schema @foo
+                """
+            )
+            extended_schema = extend_schema(schema, parse(extension_sdl))
+
+            assert print_extension_nodes(extended_schema) == extension_sdl
+
         def adds_multiple_new_root_types_via_schema_extension():
             schema = build_schema("type Query")
             extend_ast = parse(