jest-config

Base Jest Configuration for JavaScript projects

Installation

npm install --save-dev @nearmap/jest-config

Usage

Import @nearmap/jest-config in your ./jest.config.js and use it as a base for the exported configuration. You can overwrite any settings you need to change.

const config = require('@nearmap/jest-config');

module.exports = {
  ...config,
  setupFiles: [
    'src/testing/setup.js'
  ],
}

Configuration

The base configuration make some assumptions about your source code and build structure:

project-root
  ├── jest.config.js
  ├── package.json
  ├── build
  │   └── cov
  │       ├── lcov-report
  │       │   ├── base.css
  │       │   ├── index.html
  │       │   ├── index.js.html
  │       │   ├── prettify.css
  │       │   ├── prettify.js
  │       │   ├── sort-arrow-sprite.png
  │       │   └── sorter.js
  │       └── lcov.info
  └── src
      ├── foo
      │   ├── bar.js
      │   └── bar.test.js
      ├── index.js
      └── index.test.js

Tests

Tests are all files that match: ./src/**/*.test.js. Files in node_modules and build are ignored.

Babel code transforms

All .js files are transcompiled using babel-jest. Files in node_modules and build are ignored.

Mocks

By default mocks are cleared before each test but not reset.

Timers are fake.

Code Coverage

All files that match src/**/*.js must be covered fully. Reports are put out to build/cov/lcov-report.

Remember, just because you have 100% branch coverage it does not mean you have 100% use case coverage.

Do not write tests to simply get to 100% coverage.

If you find you have uncovered code, find the use case that made you add the code. If you can't find a use case maybe you don't need the code.