Add tests for merging the directives with the same name and arguments (…

…#6097)

* Add tests for merging the directives with the same name and arguments

* Fix test

packages/merge/tests/merge-typedefs.spec.ts

@@ -1704,4 +1704,17 @@ describe('Merge TypeDefs', () => {
     });
     expect(reformulatedGraphQL).toBeSimilarString(schemaWithDescription);
   });
+  it('merges the directives with the same name and same arguments', () => {
+    const directive = parse(/* GraphQL */ `
+      directive @link(
+        url: String!
+        as: String
+        import: [link__Import]
+        for: link__Purpose
+      ) on SCHEMA
+    `);
+    const typeDefs = [directive, directive];
+    const merged = mergeTypeDefs(typeDefs);
+    expect(print(merged)).toBeSimilarString(print(directive));
+  });
 });