Fix false-positive validation error for unknown type

Fixes #255

Author: leebyron

src/validation/__tests__/KnownTypeNames.js

@@ -55,4 +55,26 @@ describe('Validate: Known type names', () => {
     ]);
   });
 
+  it('ignores type definitions', () => {
+    expectFailsRule(KnownTypeNames, `
+      type NotInTheSchema {
+        field: FooBar
+      }
+      interface FooBar {
+        field: NotInTheSchema
+      }
+      union U = A | B
+      input Blob {
+        field: UnknownType
+      }
+      query Foo($var: NotInTheSchema) {
+        user(id: $var) {
+          id
+        }
+      }
+    `, [
+      unknownType('NotInTheSchema', 12, 23),
+    ]);
+  });
+
 });

src/validation/rules/KnownTypeNames.js

@@ -24,6 +24,13 @@ export function unknownTypeMessage(type: any): string {
  */
 export function KnownTypeNames(context: ValidationContext): any {
   return {
+    // TODO: when validating IDL, re-enable these. Experimental version does not
+    // add unreferenced types, resulting in false-positive errors. Squelched
+    // errors for now.
+    ObjectTypeDefinition: () => false,
+    InterfaceTypeDefinition: () => false,
+    UnionTypeDefinition: () => false,
+    InputObjectTypeDefinition: () => false,
     NamedType(node) {
       var typeName = node.name.value;
       var type = context.getSchema().getType(typeName);