TR;DR
- jestはswcで高速化出来ます。
@swc/jest
を直接使うのではなく、next/jest
経由で利用すると楽です。
※ 実際のコードはこちらのPRでご確認頂けます。
作業は以下を参考に進めます。
作業内容
# turborepoの場合 apps/web等yarn add -D jest jest-environment-jsdom @testing-library/react @testing-library/jest-dom
const nextJest = require('next/jest')
const createJestConfig = nextJest({ // Provide the path to your Next.js app to load next.config.js and .env files in your test environment dir: './'})
// Add any custom config to be passed to Jestconst customJestConfig = { // Add more setup options before each test is run // setupFilesAfterEnv: ['<rootDir>/jest.setup.js'], // if using TypeScript with a baseUrl set to the root directory then you need the below for alias' to work moduleDirectories: ['node_modules', '<rootDir>/'], testEnvironment: 'jest-environment-jsdom'}
// createJestConfig is exported this way to ensure that next/jest can load the Next.js config which is asyncmodule.exports = createJestConfig(customJestConfig)
上記の設定をすることで以下のようなことを自動でしてくれます。
Under the hood, next/jest is automatically configuring Jest for you, including:
- Setting up transform using SWC
- Auto mocking stylesheets (.css, .module.css, and their scss variants) and image imports
- Loading .env (and all variants) into process.env
- Ignoring node_modules from test resolving and transforms
- Ignoring .next from test resolving
- Loading next.config.js for flags that enable SWC transforms