Cheatsheet — Jest

Photo by Toon Lambrechts on Unsplash

Mocking

1. Mock Library methods

React Jest — Mock library methods

2. Partially Mock Library Methods

React Jest — Partially Mock Library Methods

3. Partially Mock Own methods Approach 1

React Jest — Partially Mock own methods

4. Partially Mock Own methods Approach 2

React Jest — Partially Mock Own methods Approach 2

DOM Testing

1. Shallow Testing with Enzyme

React Jest with Enzyme — Shallow Testing

2. Deep testing with Enzyme

React Jest with Enzyme — Deep Testing

3. DOM Testing with react-native-testing-library

React Jest — DOM Testing with react-native-testing-library

Coverage Report

1. Generate coverage report in watch mode for all files

yarn testCoverage --watchAll

2. Generate coverage report in watch mode for updated files

yarn testCoverage --changedSince=dev  --watch

3. Generate coverage report in watch mode for a particular file

yarn testCoverage src/feature/dashboard/DashboardScreen.test.tex --watchAll