Next app

how to create project with TypeScript, Next, eslint, prettier, Storybook, Mui and translation

create Next app
eslint
prettier
vscode setting
test
storybook
mui
translation

reference

environment Version

Node 16.16.0
npm 8.11.0

1. create Next app

1 create your app

npx create-next-app --typescript [project-name]

2 show your app

npm run dev

2. eslint

edit ./.eslintrc.json file

{
  "extends": [
    "next/core-web-vitals",
    "plugin:import/recommended",
    "plugin:import/warnings",
    "prettier"
  ],
  "rules": {
    "import/order": [
      "error",
      {
        "alphabetize": {
          "order": "asc"
        }
      }
    ],
    "semi": ["error", "always"]
  }
}

more about eslint

3. prettier

1 install prettier

npm install --save-dev prettier

2 edit ./.prettierrc file

{
  "trailingComma": "all",
  "tabWidth": 2,
  "semi": false,
  "singleQuote": true,
  "jsxSingleQuote": true,
  "printWidth": 100
}

3 edit script of ./package.json file

"scripts": {
    "dev": "next dev",
    "build": "next build",
    "start": "next start",
    "lint": "next lint --dir src",
    "lint:fix": "yarn lint --fix",
    "format": "prettier --check --ignore-path .gitignore .",
    "format:fix": "prettier --write --ignore-path .gitignore .",
  },

more about prettier

4. VsCode setting

If you change VsCode setting, you can align format when you save
you need vscode extension(eslint, prettier)

open settings.json file
open command palette(mac : cmd + shift + p/ windows : ctrl + shift + p)
type settings.json
choose Open User Settings(JSON)
add settings
(add setting tab size of typescript)

{
  "editor.defaultFormatter": "esbenp.prettier-vscode",
  "editor.formatOnSave": true,
  "editor.codeActionsOnSave": {
    "source.fixAll.eslint": true
  },
  "[typescript]": {
    "editor.tabSize": 2
  },
  "[typescriptreact]": {
    "editor.tabSize": 2
  }
}

5. test

1 install Jest and React Testing Library

npm install --save-dev jest @testing-library/react @testing-library/jest-dom jest-environment-jsdom

2 create ./jest.setup.js

// Optional: configure or set up a testing framework before each test.
// If you delete this file, remove `setupFilesAfterEnv` from `jest.config.js`

// Used for __tests__/testing-library.js
// Learn more: https://github.com/testing-library/jest-dom
import '@testing-library/jest-dom/extend-expect';

3 create ./jest.config.js

const nextJest = require('next/jest');

const createJestConfig = nextJest({
  dir: './',
});

const customJestConfig = {
  setupFilesAfterEnv: ['<rootDir>/jest.setup.js'],
  moduleDirectories: ['node_modules', '<rootDir>/'],
  testEnvironment: 'jest-environment-jsdom',
};

module.exports = createJestConfig(customJestConfig);

4 create ./tests/index/index.test.tsx

import { render, screen } from '@testing-library/react';

import Home from '../../pages/index';

describe('Home', () => {
  it('renders a heading', () => {
    const { container } = render(<Home />);

    const heading = screen.getByRole('heading', {
      name: /welcome to next\.js!/i,
    });

    expect(heading).toBeInTheDocument();

    expect(container).toMatchSnapshot();
  });
});

5 edit script of ./package.json file

"scripts": {
    (...)
    "test": "jest --watch",
    "test:ci": "jest --ci",

6 test

npm test

6. storybook

1 install storybook

npm install --save-dev sb

2 init storybook

npx sb init --builder webpack5

3 edit script of ./package.json file

"scripts": {
    (...)
    "storybook": "start-storybook -p 6006 -s ./public",
    "build-storybook": "build-storybook -s public"

4 show storybook

npm run storybook

more about storybook

7. mui

install mui and emotion

npm install --save @mui/material @emotion/react @emotion/styled

more about mui

8. translation

1 install next/translation

npm install --save next-translate

2 edit ./next.config.js file
add this

const nextTranslate = require('next-translate');

module.exports = nextTranslate();

3 create ./i18n.json file

{
  "locales": ["ja", "en"],
  "defaultLocale": "en",
  "localeDetection": false,
  "pages": {
    "*": ["common"]
  }
}

4 create ./locales/en/common.json file

{
  "Japanese": "Japanese",
  "English": "English",
}

5 create ./locales/ja/common.json file

{
  "Japanese": "日本語",
  "English": "英語",
}

6 use translation
like this

import useTranslation from 'next-translate/useTranslation';
...
const { t } = useTranslation('common');
...
{t('Japanese')}