.eslintrc.json

{
    "env": {
        "browser": true,
        // "commonjs": true,
        "es6": true,
        "node": true, // For jest, config files, etc...
        "amd": true,
        "mocha": true
    },

    "parser": "@typescript-eslint/parser",

    "parserOptions": {
        // Configure the parser with the tsconfig file in the root project
        // (or rather an extended version that add peripheral files such as rollup.config.js
        // so that eslint doesn't complain that they are not in the project)
        "project": "./tsconfig.eslint.json"

        // "ecmaFeatures": { "jsx": false }, // default
        // "ecmaVersion": 2020,
        // "sourceType": "module" // Allow the use of import
    },

    "extends": [
        // Uses the recommended rules for Typescript
        "plugin:@typescript-eslint/recommended",
        "prettier/@typescript-eslint", // Uses eslint-config-prettier to disable ESLint rules from @typescript-eslint/eslint-plugin that would conflict with prettier
        // Disable rules that conflict with prettier
        // See https://prettier.io/docs/en/integrating-with-linters.html
        "plugin:prettier/recommended"
    ],
    // See http://eslint.org/docs/rules/

    "rules": {
        /// Temporary lenient rules until more complete conversion to
        /// Typescript is completed. @revisit
        "@typescript-eslint/explicit-function-return-type": "off",
        "@typescript-eslint/no-unnecessary-type-arguments": "warn",
        "@typescript-eslint/no-untyped-public-signature": "warn",
        // "@typescript-eslint/typedef": [
        //     "warn",
        //     {
        //         "parameter": true,
        //         "arrowParameter": false,
        //         "variableDeclaration": false
        //     }
        // ],

        "@typescript-eslint/array-type": ["warn", { "default": "array" }],

        "@typescript-eslint/no-explicit-any": "off",

        "prettier/prettier": "error",

        // note you must disable the base rule as it can report incorrect errors
        "indent": "off",
        "@typescript-eslint/prefer-optional-chain": "warn",
        "@typescript-eslint/prefer-nullish-coalescing": "warn",

        "@typescript-eslint/generic-type-naming": ["warn", "^[A-Z][a-zA-Z]*$"],
        "@typescript-eslint/no-non-null-assertion": "off",
        "@typescript-eslint/no-unused-vars": [
            "error",
            {
                "argsIgnorePattern": "^_"
                // "varsIgnorePattern": "^_",
                // "vars": "all",
                // "args": "after-used",
                // "ignoreRestSiblings": false
            }
        ],
        // "@typescript-eslint/explicit-function-return-type": [
        //     "warn",
        //     {
        //         "allowExpressions": true
        //     }
        // ],
        "@typescript-eslint/no-use-before-define": [
            "error",
            {
                "functions": false,
                "classes": false,
                "variables": false,
                "typedefs": false
            }
        ],
        "@typescript-eslint/no-this-alias": [
            "error",
            {
                "allowedNames": ["self", "that"] // Allow `const self = this`; `[]` by default
            }
        ],
        "@typescript-eslint/no-for-in-array": "error",

        // Note:
        // "off" or 0 - turn the rule off
        // "warn" or 1 - turn the rule on as a warning (doesn’t affect exit code)
        // "error" or 2 - turn the rule on as an error (exit code is 1 when triggered)
        "no-const-assign": "warn",
        "no-this-before-super": "warn",
        // "no-undef": "warn",
        "no-unreachable": "warn",
        "no-unused-vars": ["warn", { "argsIgnorePattern": "^_" }],
        "constructor-super": "warn",

        "block-scoped-var": "error",

        "array-bracket-spacing": ["error", "never"],
        "block-spacing": ["error", "always"],
        "brace-style": ["warn", "1tbs", { "allowSingleLine": true }],
        "prefer-const": "warn",

        "valid-typeof": "error",
        "consistent-return": "error",
        "curly": ["warn", "multi-line"],
        "eqeqeq": ["error", "smart"],
        "guard-for-in": "warn",
        // "max-len": "warn",
        "new-cap": "warn",
        "no-bitwise": "off",
        "no-console": "off",
        "no-dupe-class-members": "off", // Support TypeScritp polymorphism
        "no-else-return": "warn",
        "no-eval": "error",
        "no-fallthrough": "error",
        "no-invalid-this": "warn",
        "no-lone-blocks": "warn",
        "no-return-assign": ["warn", "always"],
        "no-redeclare": "off",
        "no-self-compare": "error",
        "no-sequences": "warn",
        "no-unneeded-ternary": "warn",
        "no-unused-expressions": "warn",
        "no-useless-call": "warn",
        "no-var": "error",
        "no-with": "error",
        // "vars-on-top": "warn",
        "no-delete-var": "warn",
        "no-mixed-spaces-and-tabs": ["warn", "smart-tabs"],
        "require-jsdoc": "off",
        "space-infix-ops": ["error", { "int32Hint": false }],

        "no-trailing-spaces": [1, { "skipBlankLines": true }]
    }
}