test: add basic test to trigger GitHub CI on PR

mocks/chrome.js

@@ -0,0 +1,27 @@
+global.chrome = {
+  action: {
+    setIcon: jest.fn(),
+    setTitle: jest.fn(),
+  },
+  runtime: {
+    getURL: jest.fn((path) => path),
+    onMessage: {
+      addListener: jest.fn(),
+    },
+  },
+  tabs: {
+    onRemoved: {
+      addListener: jest.fn(),
+    },
+  },
+  webRequest: {
+    onHeadersReceived: {
+      addListener: jest.fn(),
+    },
+  },
+  webNavigation: {
+    onCommitted: {
+      addListener: jest.fn(),
+    },
+  },
+};

package.json

@@ -13,5 +13,8 @@
     "jest": "^29.7.0",
     "jest-puppeteer": "^10.1.2",
     "puppeteer": "^23.6.0"
+  },
+  "jest": {
+    "setupFiles": ["<rootDir>/mocks/chrome.js"]
   }
 }

src/background.js

@@ -122,3 +122,5 @@ chrome.tabs.onRemoved.addListener(function (tabId) {
 //     }
 //     return Object.keys(set);
 // }
+
+module.exports = { getClacks, extinguishClacksIcon, illuminateClacksIcon };

tests/basic.test.js

@@ -1,3 +1,4 @@
 test('Jest is working', () => {
   expect(1 + 1).toBe(2);
+  expect(true).toBe(true);
 });

tests/changeIcons.test.js

@@ -0,0 +1,41 @@
+const { getClacks, extinguishClacksIcon, illuminateClacksIcon } = require('../src/background');
+
+describe('Clacks Overhead Icon state', () => {
+  beforeEach(() => {
+    jest.clearAllMocks();
+  });
+
+  it('should set the clacks icon to active if illuminated', () => {
+    illuminateClacksIcon(1);
+
+    expect(chrome.action.setIcon).toHaveBeenCalledWith({
+      tabId: 1,
+      path: {
+        "19": "images/melanie_icon19.png",
+        "38": "images/melanie_icon38.png"
+      }
+    });
+
+    expect(chrome.action.setTitle).toHaveBeenCalledWith({
+      tabId: 1,
+      title: "Clacks icon is active"
+    });
+  });
+
+  it('should set the clacks icon to disabled if disabled', () => {
+    extinguishClacksIcon(1);
+
+    expect(chrome.action.setIcon).toHaveBeenCalledWith({
+      tabId: 1,
+      path: {
+        "19": "images/melanie_icon19_disabled.png",
+        "38": "images/melanie_icon38_disabled.png"
+      }
+    });
+
+    expect(chrome.action.setTitle).toHaveBeenCalledWith({
+      tabId: 1,
+      title: "Clacks icon is disabled"
+    });
+  });
+});

tests/puppeteer.test.js

@@ -0,0 +1,32 @@
+// Test of Puppeteer itself
+const puppeteer = require('puppeteer');
+
+describe('Puppeteer with Jest', () => {
+  let browser;
+  let page;
+
+  beforeAll(async () => {
+    browser = await puppeteer.launch();
+    page = await browser.newPage();
+  });
+
+  afterAll(async () => {
+    await browser.close();
+  });
+
+  it('should navigate to example.com and check title', async () => {
+    await page.goto('https://example.com');
+    const title = await page.title();
+    expect(title).toBe('Example Domain');
+  });
+
+  // This relies on the h1 tag being present on the page, which is not
+  // guaranteed, but has been consistent for years.
+  it ('should visit gnuterrypratchett.com and check for the h1', async () => {
+    await page.goto('http://www.gnuterrypratchett.com');
+    const h1 = await page.evaluate(() => {
+      return document.querySelector('h1').innerText;
+    });
+    expect(h1).toBe('GNU Terry Pratchett');
+  });
+});