Create 36.test.ts (#40)

spec/issues/36.test.ts

@@ -0,0 +1,20 @@
+import test from 'ava';
+
+import { Substitute, Arg } from '../../src/index';
+
+interface IData { serverCheck: Date, data: { a: any[] } }
+interface IFetch { getUpdates: (arg: Date | null) => Promise<IData>  }
+
+test('issue 36 - promises returning object with properties', async t => {
+    const emptyFetch = Substitute.for<IFetch>();
+    const now = new Date();
+    emptyFetch.getUpdates(null).returns(Promise.resolve<IData>({
+        serverCheck: now,
+        data: { a: [1] }
+    }));
+    const result = await emptyFetch.getUpdates(null);
+    t.true(result.serverCheck instanceof Date, 'given date is instanceof Date');
+    t.is(result.serverCheck, now, 'dates are the same');
+    t.true(Array.isArray(result.data.a), 'deep array isArray');
+    t.deepEqual(result.data.a, [1], 'arrays are deep equal');
+});