TypeScript + ESLint + Prettier環境構築例

.eslintrc

{
  "env": {
    "node": true,
    "es2021": true
  },
  "plugins": ["@typescript-eslint"],
  "parser": "@typescript-eslint/parser",
  "parserOptions": {
    "sourceType": "module"
  },
  "extends": [
    "eslint:recommended",
    "plugin:@typescript-eslint/recommended",
    "plugin:prettier/recommended",
    "prettier/@typescript-eslint"
  ]
}

.prettierrc.json

{
  "arrowParens": "always",
  "printWidth": 100,
  "trailingComma": "all"
}

install.sh

yarn add -D \
  typescript \
  eslint \
  prettier \
  eslint-config-prettier \
  eslint-plugin-prettier \
  @typescript-eslint/parser \
  @typescript-eslint/eslint-plugin

package.json

{
  "scripts": {
    "eslint": "eslint --ignore-path .gitignore '**/*.{ts,js}'",
    "eslint:fix": "eslint --ignore-path .gitignore '**/*.{ts,js}' --fix"
  },
  "devDependencies": {
    "@typescript-eslint/eslint-plugin": "^3.10.1",
    "@typescript-eslint/parser": "^3.10.1",
    "eslint": "^7.7.0",
    "eslint-config-prettier": "^6.11.0",
    "eslint-plugin-prettier": "^3.1.4",
    "prettier": "^2.1.1",
    "typescript": "^4.0.2"
  },
}