Vitest 4.0 Released: Browser Testing, Visual Regression & Playwright Support

Introduction

Vitest 4.0 achieves a major milestone with stable Browser Mode and visual testing features. It removes experimental tags and enhances Playwright integration for better workflows.

Browser Mode Goes Stable

Browser Mode is now stable, enabling confident integration into CI/CD pipelines. Despite API changes, it signals maturity for real-world testing scenarios.

Visual Regression Testing

Visual regression testing captures UI screenshots to detect visual changes, addressing gaps in automated workflows and providing visual validation.

Playwright Integration Enhancements

Enhanced Playwright integration generates trace files and simplifies iframe testing with frameLocator API, streamlining IDE debugging.

Extended Testing Capabilities

New features include test lifecycle hooks, schema validation, and Chai assert methods, while the basic reporter is removed.

Pros and Cons

Advantages

• Stable Browser Mode for production use
• Built-in visual regression testing
• Enhanced Playwright trace support
• Improved iframe testing
• Direct VSCode debugging
• Extended test hooks
• Schema validation

Disadvantages

• Breaking API changes
• Basic reporter removed
• Increased complexity
• Browser mode setup overhead

Conclusion

Vitest 4.0 evolves with key features now production-ready, combining browser mode, visual testing, and Playwright for modern web apps. Breaking changes require attention but solidify its position.