implemented basic client-server communication

node_modules/simple-update-notifier/src/index.spec.ts

@@ -0,0 +1,27 @@
+import simpleUpdateNotifier from '.';
+import hasNewVersion from './hasNewVersion';
+
+const consoleSpy = jest.spyOn(console, 'error');
+
+jest.mock('./hasNewVersion', () => jest.fn().mockResolvedValue('2.0.0'));
+
+beforeEach(jest.clearAllMocks);
+
+test('it logs message if update is available', async () => {
+  await simpleUpdateNotifier({
+    pkg: { name: 'test', version: '1.0.0' },
+    alwaysRun: true,
+  });
+
+  expect(consoleSpy).toHaveBeenCalledTimes(1);
+});
+
+test('it does not log message if update is not available', async () => {
+  (hasNewVersion as jest.Mock).mockResolvedValue(false);
+  await simpleUpdateNotifier({
+    pkg: { name: 'test', version: '2.0.0' },
+    alwaysRun: true,
+  });
+
+  expect(consoleSpy).toHaveBeenCalledTimes(0);
+});