extension-test — quangpl/browser-extension-skills…

How to use

Copy the installation command and review the source package before installing it in your own agent environment.
Check the source document for required tools, credentials and supported hosts.
Describe your input and desired deliverable; review the output against the source material.

npx skills add https://github.com/quangpl/browser-extension-skills --skill extension-test

Before you start

Installation does not include a model subscription, API allowance or permission to access your files.
Repository stars and installation counts describe activity, not an independent quality or security test.

Original skill document

Rendered from the source repository. Headings, examples, code, tables, links, and referenced images are preserved.

Extension Testing

🚀 Upgrade to Premium Get the Premium version at https://app.extensionbooster.net/dashboard/services/extension-ai-kit

Testing Layer Architecture

Unit Tests (Jest)          → Test isolated logic, chrome.* API mocks
Integration Tests (Jest)   → Test service interactions, message passing
E2E Tests (Puppeteer)      → Test in real Chrome with extension loaded

Critical constraint: Extensions CANNOT run in headless mode. E2E requires headless: false or Chrome's --headless=new (Chrome 112+).

Layer 1: Unit + Integration (Jest)

Install

bash

npm install -D jest @types/jest ts-jest jest-chrome
# For React popup:
npm install -D @testing-library/react @testing-library/jest-dom jsdom

jest.config.ts

export default {
  preset: "ts-jest",
  testEnvironment: "jsdom",
  setupFilesAfterEnv: ["./jest.setup.ts"],
  moduleNameMapper: {
    "^@/(.*)$": "<rootDir>/src/$1",
  },
};

jest.setup.ts (minimal)

import chrome from "jest-chrome";
Object.assign(global, { chrome });

Full mock setup → chrome-api-mocks.md Unit/integration patterns → unit-integration-testing.md

Layer 2: E2E (Puppeteer)

Install

bash

npm install -D puppeteer

Launch extension in Chrome

import puppeteer from "puppeteer";
import path from "path";

const browser = await puppeteer.launch({
  headless: false, // extensions require non-headless
  args: [
    `--disable-extensions-except=${path.resolve("dist")}`,
    `--load-extension=${path.resolve("dist")}`,
  ],
});

Get extension ID

const targets = await browser.targets();
const extTarget = targets.find((t) => t.type() === "service_worker");
const extUrl = extTarget?.url() ?? "";
const [, , extId] = extUrl.split("/");

Full E2E patterns → e2e-testing-puppeteer.md

Chrome API Mocking Strategy

API	Approach
`chrome.storage`	Mock with in-memory store
`chrome.runtime.sendMessage`	jest.fn() + mock response
`chrome.tabs`	jest.fn() with createMockTab helper
`chrome.action`	jest.fn() stubs
`chrome.alarms`	jest.fn() stubs

All mocks → chrome-api-mocks.md

package.json Scripts

json

{
  "scripts": {
    "test:unit": "jest --testPathPattern=unit",
    "test:integration": "jest --testPathPattern=integration",
    "test:e2e": "jest --testPathPattern=e2e --runInBand",
    "test": "npm run test:unit && npm run test:integration"
  }
}

Run E2E separately (--runInBand) — Puppeteer tests must run serially.

Reference Files

unit-integration-testing.md — Jest patterns, mocking, component tests
e2e-testing-puppeteer.md — Puppeteer setup, popup/content/SW tests
chrome-api-mocks.md — Full chrome.* mock templates