Why test-staged?

The Problem

As projects grow, the number of tests increases. Running the entire test suite before every commit becomes slow and impractical.

Developers often skip running tests locally because it takes too long, relying on CI to catch issues. This results in a slow feedback loop:

1. Commit changes.
2. Push to remote.
3. Wait for CI to fail.
4. Fix and repeat.

The Solution

test-staged aims to solve this by running only the tests related to your staged changes.

It intelligently determines which tests need to be run based on the files you are about to commit:

• If you change a component, it runs the tests for that component.
• If you change a utility function, it runs all tests that import that utility (when supported by the runner).

This provides immediate feedback, preventing broken code from being committed while keeping the pre-commit check fast.

How is it different from lint-staged?

We love lint-staged! It's an amazing tool for running linters and formatters on staged files. However, running tests is different.

• lint-staged runs commands on the staged files themselves.
• test-staged runs commands (tests) related to the staged files.

For example, if you modify Button.tsx:

• lint-staged might run eslint Button.tsx.
• test-staged will look for Button.test.tsx (or any other test file that imports Button.tsx) and run that.

Disclaimer

test-staged is designed to be a "fast feedback" tool for your local development workflow. It is not a replacement for running your full test suite in your CI/CD pipeline.

While "related" mode is powerful, static analysis might miss some edge cases (e.g., dynamic imports or complex dependency injection). Always ensure your full test suite passes before merging to production.

Credits

This project was heavily inspired by lint-staged.

We want to express our sincere gratitude to the lint-staged team for their incredible work and for establishing the pattern of running checks on staged files. test-staged aims to be the perfect companion to lint-staged in your pre-commit workflow.