vitest-testing

What This Skill Does

The vitest-testing skill provides comprehensive support for the Vitest framework, the leading unit testing tool for the Vite ecosystem. It acts as an expert assistant that understands the nuance of modern JavaScript and TypeScript testing. Whether you are migrating from Jest, setting up a new project, or debugging complex asynchronous code, this skill provides the context needed to write clean, maintainable, and robust test suites. It handles everything from simple assertions and object deep equality checks to sophisticated mocking, timer manipulation, and environment configuration.

Installation

To integrate this skill into your environment, run the following command in your terminal: clawhub install openclaw/skills/skills/anderskev/vitest-testing Ensure that you have Vitest installed as a development dependency in your project's package.json to allow the agent to verify your local configuration against the framework's best practices.

Use Cases

• Unit Testing: Writing isolated tests for individual functions or components, ensuring logic paths are covered with edge cases.
• Integration Testing: Orchestrating multiple modules to verify that they work together correctly, utilizing vi.mock to stub dependencies.
• Configuration Management: Optimizing vitest.config.ts files, setting up coverage reporters, and defining test environments like jsdom or node.
• Mocking Strategy: Creating consistent mock environments for APIs, timers, and external services to maintain deterministic test results.
• Refactoring: Safely modifying existing code by creating a robust suite of regression tests before executing changes.

Example Prompts

1. "Create a Vitest unit test for my calculateTax function that covers the standard rate, high-income threshold, and invalid input scenarios."
2. "I am having trouble mocking an external module with vi.mock. Here is my current code, can you identify why the mock isn't being applied correctly?"
3. "Convert my existing Jest test file to Vitest syntax, ensuring that my beforeEach hooks and snapshot assertions are migrated accurately."

Tips & Limitations

To get the best performance, always ensure you are using await with promise-based assertions. A common pitfall is failing to await expect(promise).resolves, which can lead to false positives where tests pass even if the code fails. Always use vi.clearAllMocks() or vi.resetAllMocks() in your cleanup hooks to prevent state pollution between tests, which is the most frequent source of flaky test suites. While this skill is highly effective at writing boilerplate and configuration, always review mock logic to ensure it accurately reflects real-world API behavior. For complex system interactions, consider combining this with integration testing tools to verify that your mocks haven't diverged from actual interface implementations.