Best of Vitest — 2025

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    Article
    Avatar of storybookStorybook·51w

    Storybook 9

    Storybook 9 introduces comprehensive component testing capabilities powered by Vitest and Playwright. The release features interaction tests, accessibility testing, visual regression testing, and coverage reports all integrated into a unified testing experience. Key improvements include a 48% smaller bundle size, story generation tools, tag-based organization, and story-level globals. Framework updates include Vite-powered Next.js support, Svelte 5 compatibility, and enhanced React Native integration.

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    Article
    Avatar of typescripttvTypeScript.TV·39w

    Testing Types in TypeScript

    Explores essential techniques for testing TypeScript types to ensure predictable type inferences in SDKs and APIs. Covers multiple approaches from basic compiler checks using tsc and @ts-expect-error to dedicated tools like dtslint, tsd, and Vitest's expectTypeOf helper. Emphasizes the importance of type testing for library authors to guarantee consistent type behavior across refactors and prevent developer frustration.

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    Article
    Avatar of svelteSvelte Blog·47w

    What’s new in Svelte: July 2025

    Svelte ecosystem updates include Vite 7 and Rolldown support in SvelteKit for faster compilation, improved $inspect.trace logging with source names, and Vitest browser mode support in the CLI. The community showcased new apps like Planet Poster and Prodcast, while libraries received major updates including shadcn-svelte v1.0 release and Storybook 9 with Svelte 5 support.

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    Article
    Avatar of storybookStorybook·49w

    Frontend test coverage with Storybook 9

    Storybook 9 introduces comprehensive frontend test coverage tracking that measures how much component code is exercised by stories. The new workflow allows developers to run interaction, accessibility, and visual tests with a single command, identify untested components and code branches, and quickly fill coverage gaps by generating new stories. This approach provides high coverage of UI states while being faster and more reliable than end-to-end tests, though it complements rather than replaces them for full application testing.

  5. 5
    Article
    Avatar of jetbrainsJetBrains·24w

    WebStorm 2025.3: Enhanced Monorepo Support, Framework Improvements, Vitest 4 Support, Multiple Agents in AI Assistant, Remote Debugging, and More

    WebStorm 2025.3 introduces a service-powered TypeScript type engine for better performance and accuracy, enhanced monorepo support with improved pnpm and Nx workspace handling, and remote debugging capabilities for JavaScript projects in WSL and Docker. The release adds Vitest 4 support, integrates Claude Agent and Junie in the AI Assistant, updates CSS syntax to align with WebRef specifications including new math functions, and consolidates Node.js, Bun, and Deno configuration into a unified JavaScript Runtime settings page. Additional improvements include Angular 20.2 template syntax support, Vue 3.6 Vapor mode recognition, Astro parser fixes, and a new Prettier language status widget.

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    Article
    Avatar of twirThis Week In React·1y

    This Week In React #228: React 19.1, Next.js deployment, React-Email, Triplex, Tinybase, Rspack, i18n-check, React-Admin

    React 19.1 introduces better error handling and deeper integration with Server Components in Parcel. Tailwind CSS 4.1 is coming soon. The React Native community sees the release of React Native 0.79 Golden RC and updates to ExecuTorch with new AI features. Notable mentions include Tinybase 6.0, React-Admin 5.7, and Rspack 1.3. Updates also highlight implications for Xcode 16.3 and new features in WebKit's Safari 18.4.

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    Article
    Avatar of nxNx·26w

    Nx 22.1 Release: Terminal UI on Windows, Storybook 10, Vitest 4, and more!

    Nx 22.1 introduces Terminal UI support for Windows users, enabling the same task management experience previously available only on Mac and Linux. The release adds Storybook 10 support with AI-powered ESM migration assistance, splits Vitest into a dedicated plugin with atomizer support for parallel test execution, and includes compatibility updates for Next.js v16 and Cypress v15. Angular 21 support with Vitest as the default test runner is coming in version 22.2.

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    Article
    Avatar of collectionsCollections·30w

    Angular 21: A New Era of Testing with Vitest and Testronaut

    Angular 21 replaces Jasmine with Vitest as the default testing framework, chosen for its browser mode compatibility and alignment with the modern JavaScript ecosystem. The update includes stable zoneless mode implementation, deprecating legacy utilities like fakeAsync() in favor of fake timers. Additionally, Angular introduces Testronaut, a Playwright-based component testing runner that enables full browser testing without requiring Vite compilation. These changes modernize Angular's testing capabilities and improve integration with the broader JavaScript development ecosystem.

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    Article
    Avatar of tiaThis is Angular·32w

    Ng-News 25/41: Future Testing Framework: Vitest or Jest?

    Angular's testing tooling is evolving, with recent pull requests suggesting a shift from Jest to Vitest as the future test runner. While multiple Vitest migration PRs have been merged, the Angular team clarifies no final decision has been made yet. The current official setup remains Jasmine and Karma, though Karma is deprecated. Meanwhile, Playwright 1.56 introduces AI-assisted testing with three agents (planner, generator, healer) to automate test creation and repair. Community resources include comprehensive guides on Angular SSR and performance optimization tips for Largest Contentful Paint.

  10. 10
    Video
    Avatar of communityCommunity Picks·48w

    Why Every Next.js Project NEEDS Storybook 9

    Storybook 9 introduces significant improvements including Vitest integration, Svelte 5 and React Native support, automatic story generation, and the ability to run Next.js components in Vite. The new version is 48% leaner, faster, and includes built-in accessibility testing, visual regression testing with Chromatic, and Playwright integration. It automatically generates stories based on component props and provides comprehensive documentation capabilities, making it essential for teams building component systems.

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    Article
    Avatar of storybookStorybook·43w

    Component Test with Storybook and Vitest

    Storybook 9 introduces comprehensive component testing powered by Vitest, offering three types of tests: interaction tests for user behavior simulation, accessibility tests using axe-core for WCAG compliance, and visual tests through Chromatic for UI regression detection. The new Test widget enables running all tests with one click, includes coverage reports, and provides debugging panels. This approach fills the gap between unit tests and E2E tests, allowing developers to test thousands of UI states with minimal maintenance while leveraging existing stories as test cases.

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