fix: check the actual GraphQLDirective instance in isSpecifiedDirective

Author: ardatan

src/type/__tests__/predicate-test.ts

@@ -700,5 +700,13 @@ describe('Directive predicates', () => {
     it('returns false for custom directive', () => {
       expect(isSpecifiedDirective(Directive)).to.equal(false);
     });
+
+    it('returns false for the directives with the same name as specified directives', () => {
+      const FakeSkipDirective = new GraphQLDirective({
+        name: 'skip',
+        locations: [DirectiveLocation.QUERY],
+      });
+      expect(isSpecifiedDirective(FakeSkipDirective)).to.equal(false);
+    });
   });
 });

src/type/directives.ts

@@ -233,5 +233,5 @@ export const specifiedDirectives: ReadonlyArray<GraphQLDirective> =
   ]);
 
 export function isSpecifiedDirective(directive: GraphQLDirective): boolean {
-  return specifiedDirectives.some(({ name }) => name === directive.name);
+  return specifiedDirectives.some(specifiedDirective => specifiedDirective === directive);
 }