supabase/supabase

Overview

This skill provides a fast, Vite-native unit testing framework with a Jest-compatible API. It supports native ESM, TypeScript, and JSX out of the box and leverages Vite's transform pipeline for extremely fast test runs. Use it to write, run, and maintain unit tests with familiar Jest-style APIs while benefiting from Vite performance and multi-threaded execution.

How this skill works

The skill runs tests using Vite's build pipeline so tests update quickly and only affected modules re-run in watch mode. It exposes test/it, describe, expect, and vi utilities for writing assertions, mocks, spies, and timers. Coverage can be collected via V8 or Istanbul, and tests can be executed concurrently across worker threads or sharded across projects.

When to use it

• When migrating Jest suites to a faster, Vite-native runner with minimal API changes
• When you need native ESM, TypeScript, or JSX test support without extra config
• When you want smart watch behavior that reruns only affected tests
• When you require parallel execution, sharding, or multi-project test setups
• When you need built-in features like mocking, snapshots, and coverage

Best practices

• Reuse your Vite config via defineConfig to keep build and test behavior aligned
• Prefer vi utilities for mocks and spies to ensure hoisting and consistency
• Use watch mode during development to get HMR-like fast feedback on changes
• Collect coverage with V8 for speed, switch to Istanbul if you need advanced reporting
• Group related tests using describe/suite and isolate state with beforeEach/afterEach hooks

Example use cases

• Running unit tests for a TypeScript Next.js or Vite app without extra transpilation steps
• Migrating Jest-based test suites to a faster runner while keeping most tests unchanged
• Testing components that use ESM imports, JSX, or new JS features natively
• Setting up CI with parallel workers and sharding to reduce overall test time
• Building complex fixture setups with test.extend and custom test contexts