.eslintrc.json

{
  "ignorePatterns": ["build/"],

  "env": {
    "browser": true,
    "node": true,
    "jest": true,
    "es2022": true
  },

  "parserOptions": {
    "ecmaVersion": "latest",
    "sourceType": "module"
  },

  "rules": {
    /** Errors **/
    "camelcase": ["error", { "properties": "never" }],
    "no-array-constructor": "error",
    "no-iterator": "error",
    "no-nested-ternary": "error",
    "no-new-object": "error",
    "no-proto": "error",

    /** Warnings **/
    "max-depth": ["warn", { "max": 5 }],
    "max-params": ["warn", { "max": 5 }],
    "no-restricted-syntax": ["warn", "ClassDeclaration", "SwitchStatement"],
    "no-unused-vars": ["warn", { "vars": "all", "args": "none" }],

    /** Fixable **/
    "arrow-parens": ["warn", "always"],
    "brace-style": ["warn", "stroustrup", { "allowSingleLine": true }],
    "no-var": "warn",
    "prefer-const": "warn",
    "prefer-template": "warn",
    "quotes": ["warn", "single", { "allowTemplateLiterals": true }],
    "semi": ["warn", "always"],

    /** Whitespace **/
    "array-bracket-spacing": ["warn", "never"],
    "arrow-spacing": ["warn", { "before": false, "after": false }],
    "comma-spacing": ["warn", { "before": false, "after": true }],
    "indent": ["warn", "tab", { "MemberExpression": "off" }],
    "linebreak-style": "off",
    "no-trailing-spaces": "warn",
    "no-whitespace-before-property": "warn",
    "object-curly-spacing": ["warn", "always"],
    "space-in-parens": ["warn", "never"],
    "template-curly-spacing": ["warn", "never"],
    "keyword-spacing": ["warn", {
      "before": true,
      "after": true,
      "overrides": {
        "if": { "before": false, "after": false }
      }
    }],
    "key-spacing": ["warn", {
      "multiLine": { "beforeColon": true, "afterColon": true, "align": "colon" },
      "singleLine": { "beforeColon": false, "afterColon": true }
    }]
  }
}