Adding a test

src/workers/dispatcher-worker.test.js

@@ -1,5 +1,9 @@
 import worker from './dispatcher-worker';
 
+jest.mock('../db', () => ({
+  initDb: () => 'called initDb',
+}));
+
 describe('The dispatcher-worker ', () => {
   let port;
   beforeEach(() => {
@@ -12,11 +16,18 @@ describe('The dispatcher-worker ', () => {
     expect(port.onmessage).toBeDefined();
     expect(port.postMessage).not.toBeCalled();
   });
-  test('receives a ping and sends a pong', () => {
+  test('receives a ping and sends back an unknownAction', () => {
-    port.onmessage({ data: { id: 5, payload: 'ping' } });
+    port.onmessage({ data: { id: 5, payload: { action: 'ping' } } });
     expect(port.postMessage).toBeCalledWith({
       id: 5,
       payload: 'unknownAction',
     });
   });
+  test('calls initDb when required', async () => {
+    await port.onmessage({ data: { id: 5, payload: { action: 'initDb' } } });
+    expect(port.postMessage).toBeCalledWith({
+      id: 5,
+      payload: 'called initDb',
+    });
+  });
 });