.eslintrc.json

{
    "extends": ["eslint:recommended", "plugin:prettier/recommended"],
    "plugins": ["prettier"],
    "env": {
        "browser": true,
        "es6": true,
        "node": true,
        "jest": true
    },
    "parserOptions": {
        "ecmaVersion": 2020
    },
    "rules": {
        "prettier/prettier": [
            "error",
            {
                "insertPragma": true,
                "requirePragma": true,
                "nestedBinaryExpressions": false,
                "enforceForArrowConditionals": false
            }
        ],
        "comma-spacing": ["error", {"before": false, "after": true}],
        "no-console": "warn",
        "no-extra-parens": "off",
        "no-loss-of-precision": "error",
        "no-promise-executor-return": "off",
        "no-template-curly-in-string": "error",
        "no-unreachable-loop": "error",
        "require-atomic-updates": "error",
        "no-useless-backreference": "error",
        // Best practices
        "array-callback-return": ["error", {"checkForEach": true}],
        "block-scoped-var": "error",
        "consistent-return": "error",
        "curly": "error",
        "default-case": "error",
        "default-case-last": "error",
        "default-param-last": "error",
        "dot-notation": "error",
        "eqeqeq": "error",
        "no-constructor-return": "error",
        "no-else-return": "error",
        "no-extra-bind": "error",
        "no-multi-spaces": "error",
        "no-underscore-dangle": "error",
        "no-sequences": "error",
        "no-unused-expressions": "warn",
        "prefer-regex-literals": "warn",
        "valid-jsdoc": ["error", {"requireReturn": false}],
        // Strict mode
        "strict": "error",
        // Variables
        "no-shadow": "error",
        "no-undefined": "error",
        "no-use-before-define": "error",
        // Stylistic issues
        "array-bracket-newline": ["error", "consistent"],
        "array-bracket-spacing": ["error", "never"],
        "array-element-newline": ["error", "consistent"],
        "block-spacing": "error",
        "brace-style": "error",
        "camelcase": ["error", {"ignoreDestructuring": true, "ignoreGlobals": true}],
        "comma-dangle": ["error", "only-multiline"],
        "computed-property-spacing": ["error", "never", {"enforceForClassMembers": true}],
        "consistent-this": ["error", "self"],
        "eol-last": ["error", "always"],
        "func-call-spacing": ["error", "never"],
        "func-style": ["error", "declaration", {"allowArrowFunctions": true}],
        "indent": ["error", 4, {"SwitchCase": 1}],
        "keyword-spacing": "error",
        "linebreak-style": ["error", "unix"],
        "max-len": ["error", 120, {"ignoreComments": true}],
        "multiline-comment-style": ["error", "starred-block"],
        "new-cap": ["error", {"properties": false}],
        "new-parens": "error",
        "newline-per-chained-call": "off",
        "no-multi-assign": "error",
        "no-multiple-empty-lines": ["error", {"max": 1}],
        "no-trailing-spaces": "error",
        "object-curly-spacing": ["error", "never"],
        "padded-blocks": ["error", "never"],
        "quotes": ["error", "single", {"avoidEscape": true}],
        "semi": ["error", "always"],
        "semi-style": ["error", "last"],
        "space-before-function-paren": [
            "error",
            {
                "anonymous": "always",
                "named": "never",
                "asyncArrow": "never"
            }
        ],
        "space-in-parens": ["error", "never"],
        "spaced-comment": ["error", "always"],
        // ECMAScript 6
        "arrow-parens": ["error", "always"],
        "arrow-spacing": "error",
        "no-confusing-arrow": "error",
        "no-var": "error",
        "prefer-const": "error",
        "prefer-spread": "error"
    }
}