Jest

→ jest-expo Documentation

What create-faster adds

The jest-expo preset wired up with React Native Testing Library and the Babel transform Expo's Metro config does not ship for tests.

Files added:

jest.config.js              # jest-expo preset
babel.config.js             # babel-preset-expo (required by the jest transform)
tests/
└── unit/
    └── example.test.tsx    # Sample component test

jest.config.js

module.exports = {
  preset: 'jest-expo',
};

babel.config.js

The Expo stack relies on Metro's built-in transform and ships no babel.config.js. Jest needs one to transform JSX and TypeScript:

module.exports = (api) => {
  api.cache(true);
  return {
    presets: ['babel-preset-expo'],
  };
};

Scripts:

• test - Run the suite (jest)
• test:watch - Watch mode (jest --watch)

The Expo tsconfig.json already includes **/*.tsx, so test files under tests/ are type-checked without changes.