Testing
WebXR API Testing with Playwright and Mock Devices
WebXR brings immersive experiences to the browser, but it introduces a testing gap that trips up most teams.
JavaScript
Latest
Testing
Testing PDF Generation with Puppeteer: Visual Diffs, Text Extraction, and Layout Assertions
Puppeteer's page.pdf() generates PDFs from HTML pages — but verifying the output requires more than file existence checks. This guide covers testing PDF content via text extraction, visual regression diffs, layout assertions, and metadata checks using Node.js, Puppeteer, and the pdf-parse library. Key Takeaways Use pdf-
Testing
Testing Strapi v5 REST and GraphQL APIs with Jest and Supertest
Strapi v5 exposes content via REST and GraphQL APIs. Testing these APIs involves three layers: unit tests for custom service logic, integration tests against a running Strapi instance with a test database, and permission tests that verify role-based access. This guide covers all three using Jest and Supertest. Key
Testing
Testing Contentful Content Models and Delivery API Integration
Contentful doesn't have a built-in testing framework, but its Delivery API client, content model structure, and rich text renderer are all testable in Jest. This guide covers mocking the Contentful SDK, testing content model shape assumptions, validating rich text output, and writing integration tests against the Preview
Test Automation
Solid.js Testing Guide: Vitest + @solidjs/testing-library (2026)
Solid.js is fast by design — fine-grained reactivity, no virtual DOM, components that run once.
Test Automation
Qwik City Testing Guide: @builder.io/qwik Testing Utilities (2026)
Qwik's resumability model is fundamentally different from hydration. Components serialize their state into HTML, and execution resumes exactly where the server left off — no JavaScript re-execution, no reconciliation. That makes Qwik fast, but it also means your test setup needs to account for how Qwik actually runs
Test Automation
HTMX Testing Guide: Playwright and Server-Side Assertions (2026)
HTMX flips the standard SPA model: instead of JSON APIs and client-side rendering, the server returns HTML fragments that swap into the page.
Test Automation
Stencil.js Web Components Testing: Unit and E2E Guide (2026)
Stencil generates standard Web Components — Custom Elements with Shadow DOM — that run in any framework or vanilla HTML.
Test Automation
Lit Element Testing Guide: @web/test-runner and open-wc (2026)
Lit builds on the Web Components standard — LitElement extends HTMLElement directly, uses the browser's native Custom Elements and Shadow DOM APIs, and adds a reactive property system and tagged template literal rendering. The result is small, fast web components that work anywhere. Testing Lit components requires real browser
JavaScript
Testing Async JavaScript: Promises, async/await, and Fake Timers in Jest/Vitest
Async JavaScript is everywhere — fetch calls, timers, event handlers, database queries.
Testing
ESLint + Jest Quality Gates in GitHub Actions: A Complete Setup Guide
ESLint catches code style and quality issues; Jest enforces behavior through tests. Combined in GitHub Actions quality gates, they block merges when code doesn't meet your team's standards. This guide covers the complete setup — from configuration to PR annotations and coverage enforcement. Why Quality Gates, Not
Testing
WebdriverIO with TypeScript: Setup and Best Practices
WebdriverIO has first-class TypeScript support — types ship with the package, the setup wizard generates TypeScript configs, and the entire API surface is typed. Using TypeScript with WebdriverIO catches selector mistakes at compile time, gives you IDE autocomplete for browser APIs, and makes page objects more maintainable. This guide covers