# @repodog/jest-config

The Repodog Jest config.

[![npm version](https://badge.fury.io/js/%40repodog%2Fjest-config.svg)](https://badge.fury.io/js/%40repodog%2Fjest-config)
[![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](LICENSE)

## Install package and peer dependencies

```shell
# terminal
npm install @repodog/jest-config @jest/globals jest suppress-experimental-warnings --save-dev
```

## Install optional peer dependencies

```shell
# terminal
npm install babel-jest --save-dev
# or
npm install @swc/jest --save-dev
```

## Use package

### With Babel

```jsonc
// package.json
{
  "scripts": {
    // esm
    "test": "node --require=suppress-experimental-warnings --experimental-vm-modules node_modules/jest/bin/jest.js",
    // or cjs
    "test": "MODULE_SYSTEM=cjs node node_modules/jest/bin/jest.js",
  },
}
```

```javascript
// jest.config.mjs
import jestConfig from '@repodog/jest-config';

export default {
  ...jestConfig(),
};
```

```jsonc
// .vscode/launch.json
{
  "configurations": [
    {
      "type": "node",
      "request": "launch",
      "name": "Jest - current file",
      "program": "${workspaceFolder}/node_modules/jest/bin/jest",
      "args": ["${relativeFile}"],
      "env": {
        "DEBUG": "true",
        // esm
        "NODE_OPTIONS": "--experimental-vm-modules",
        // or cjs
        "MODULE_SYSTEM": "cjs",
      },
      "console": "integratedTerminal",
    },
  ],
}
```

### With SWC

```jsonc
// package.json
{
  "scripts": {
    // esm
    "test": "COMPILER=swc node --require=suppress-experimental-warnings --experimental-vm-modules node_modules/jest/bin/jest.js",
    // or cjs
    "test": "COMPILER=swc MODULE_SYSTEM=cjs node node_modules/jest/bin/jest.js",
  },
}
```

```javascript
// jest.config.mjs
import jestConfig from '@repodog/jest-config';
import swcConfig from '@repodog/swc-config';

export default {
  ...jestConfig({ compilerOptions: swcConfig }),
};
```

```jsonc
// .vscode/launch.json
{
  "configurations": [
    {
      "type": "node",
      "request": "launch",
      "name": "Jest - current file",
      "program": "${workspaceFolder}/node_modules/jest/bin/jest",
      "args": ["${relativeFile}"],
      "env": {
        "DEBUG": "true",
        "COMPILER": "swc",
        // esm
        "NODE_OPTIONS": "--experimental-vm-modules",
        // or cjs
        "MODULE_SYSTEM": "cjs",
      },
      "console": "integratedTerminal",
    },
  ],
}
```

### Fail on console output

The config is set up to fail a test run if anything is printed out to the console. When using JSDom, this includes any DOM warnings or errors.

If you do not want this behaviour, you need to override the `setupFilesAfterEnv` and `testEnvironment` options exported by the config.

### Environment variables

#### `COMPILER` = `'babel' || 'swc'`

Uses either Babel or SWC to compile code for Jest. Default `'babel'`.

#### `MODULE_SYSTEM` = `'esm' || 'cjs'`

Sets the module sytem to either ESModules or commonjs. Default `'esm'`.

#### `DEBUG` = `'true' || 'false'`

Changes `testMatch` to cover all test files and disables the Jest timeout. These are useful to set when debugging a file in IDE. Default `'false'`.

#### `JS_ENV` = `'web' || 'node'`

When set to `'web'`, adds regexes to `moduleNameMapper` and `transform` to cater for `.css` and other file extensions Jest cannot resolve. Default `'node'`.