.eslintrc.js

// Rules reference: http://eslint.org/docs/rules/
module.exports = {
    "env": {
        "browser": true,
        "node": true,
        "es6": true,
        "mocha": true
    },

    "parser": "@typescript-eslint/parser",
    "parserOptions": {
        "ecmaVersion": 2018
    },

    "overrides": [
        {
            "files": ["**/*.ts", "**/*.tsx"],
            "extends": [
                "plugin:@typescript-eslint/recommended",
            ],
            "rules": {
                "@typescript-eslint/no-parameter-properties": 2,
                "@typescript-eslint/no-explicit-any": 0,
                "@typescript-eslint/no-var-requires": 2,
                "@typescript-eslint/no-non-null-assertion": 2,
                "@typescript-eslint/no-use-before-define": 2,
                "@typescript-eslint/camelcase": 0,
                "@typescript-eslint/no-empty-interface": 2,
                "@typescript-eslint/explicit-function-return-type": 2,
                "@typescript-eslint/ban-ts-ignore": 0,
                "@typescript-eslint/ban-ts-comment": 0,
                "@typescript-eslint/explicit-module-boundary-types": 0,
                "@typescript-eslint/no-inferrable-types": [2, {
                    "ignoreParameters": true,
                    "ignoreProperties": true,
                }]
            }
        }
    ],

    "rules": {
        //=========================================================================
        //==================== Possible Errors ====================================
        //=========================================================================

        // disallow trailing commas in object literals
        "comma-dangle": [2, "always-multiline"], //TODO: need discussion
        // disallow assignment in conditional expressions
        "no-cond-assign": [2, "always"],
        // disallow use of console
        "no-console": 1,
        // disallow use of constant expressions in conditions
        "no-constant-condition": [2, {"checkLoops": false}],
        // disallow control characters in regular expressions
        "no-control-regex": 2,
        // disallow use of debugger
        "no-debugger": 2,
        // disallow duplicate arguments in functions
        "no-dupe-args": 2,
        // disallow duplicate keys when creating object literals
        "no-dupe-keys": 2,
        // disallow a duplicate case label.
        "no-duplicate-case": 2,
        // disallow the use of empty character classes in regular expressions
        "no-empty-character-class": 2,
        // disallow empty statements
        "no-empty": 2,
        // disallow assigning to the exception in a catch block
        "no-ex-assign": 2,
        // disallow double-negation boolean casts in a boolean context
        "no-extra-boolean-cast": 2,
        // disallow unnecessary parentheses
        "no-extra-parens": [2, "functions"],
        // disallow unnecessary semicolons
        "no-extra-semi": 2,
        // disallow overwriting functions written as function declarations
        "no-func-assign": 2,
        // disallow function or variable declarations in nested blocks
        "no-inner-declarations": 2,
        // disallow invalid regular expression strings in the RegExp constructor
        "no-invalid-regexp": 2,
        // disallow irregular whitespace outside of strings and comments
        "no-irregular-whitespace": 2,
        // disallow negation of the left operand of an in expression
        "no-negated-in-lhs": 2,
        // disallow the use of object properties of the global object (Math and JSON) as functions
        "no-obj-calls": 2,
        // disallow multiple spaces in a regular expression literal
        "no-regex-spaces": 2,
        // disallow sparse arrays
        "no-sparse-arrays": 2,
        // Avoid code that looks like two expressions but is actually one
        "no-unexpected-multiline": 2,
        // disallow unreachable statements after a return, throw, continue, or break statement
        "no-unreachable": 2,
        // disallow comparisons with the value NaN
        "use-isnan": 2,
        // ensure JSDoc comments are valid
        "valid-jsdoc": [2, {
            "requireReturn": false,
            "requireReturnDescription": false
        }],
        // ensure that the results of typeof are compared against a valid string
        "valid-typeof": 2,

        //=========================================================================
        //==================== Best Practices =====================================
        //=========================================================================
        // Enforces getter/setter pairs in objects
        "accessor-pairs": 2,
        // treat var statements as if they were block scoped
        "block-scoped-var": 2,
        // specify the maximum cyclomatic complexity allowed in a program
        "complexity": [0, 11],
        // require return statements to either always or never specify values
        "consistent-return": 2,
        // specify curly brace conventions for all control statements
        "curly": [2, "multi-line"],
        // require default case in switch statements
        "default-case": 2,
        // encourages use of dot notation whenever possible
        "dot-notation": [2, {"allowKeywords": true}],
        // enforces consistent newlines before or after dots
        "dot-location": [2, "property"],
        // require the use of === and !==
        "eqeqeq": 2,
        // make sure for-in loops have an if statement
        "guard-for-in": 2,
        // disallow the use of alert, confirm, and prompt
        "no-alert": 2,
        // disallow use of arguments.caller or arguments.callee
        "no-caller": 2,
        // disallow lexical declarations in case clauses
        "no-case-declarations": 2,
        // disallow division operators explicitly at beginning of regular expression
        "no-div-regex": 2,
        // disallow else after a return in an if
        "no-else-return": 2,
        // disallow use of empty destructuring patterns
        "no-empty-pattern": 2,
        // disallow comparisons to null without a type-checking operator
        "no-eq-null": 2,
        // disallow use of eval()
        "no-eval": 2,
        // disallow adding to native types
        "no-extend-native": 2,
        // disallow unnecessary function binding
        "no-extra-bind": 2,
        // disallow fallthrough of case statements
        "no-fallthrough": 2,
        // disallow the use of leading or trailing decimal points in numeric literals
        "no-floating-decimal": 2,
        // disallow the type conversions with shorter notations
        "no-implicit-coercion": 2,
        // disallow use of eval()-like methods
        "no-implied-eval": 2,
        // disallow this keywords outside of classes or class-like objects
        "no-invalid-this": 0,
        // disallow usage of __iterator__ property
        "no-iterator": 2,
        // disallow use of labeled statements
        "no-labels": 2,
        // disallow unnecessary nested blocks
        "no-lone-blocks": 2,
        // disallow creation of functions within loops
        "no-loop-func": 2,
        // disallow the use of magic numbers
        "no-magic-numbers": 0, //TODO: need discussion
        // disallow use of multiple spaces
        "no-multi-spaces": 2,
        // disallow use of multiline strings
        "no-multi-str": 2,
        // disallow reassignments of native objects
        "no-native-reassign": 2,
        // disallow use of new operator for Function object
        "no-new-func": 2,
        // disallows creating new instances of String,Number, and Boolean
        "no-new-wrappers": 2,
        // disallow use of new operator when not part of the assignment or comparison
        "no-new": 2,
        // disallow use of octal escape sequences in string literals, such as
        // var foo = "Copyright \251";
        "no-octal-escape": 2,
        // disallow use of (old style) octal literals
        "no-octal": 2,
        // disallow reassignment of function parameters
        "no-param-reassign": 2,
        // disallow use of process.env
        "no-process-env": 2,
        // disallow usage of __proto__ property
        "no-proto": 2,
        // disallow declaring the same variable more then once
        "no-redeclare": 2,
        // disallow use of assignment in return statement
        "no-return-assign": 2,
        // disallow use of `javascript:` urls.
        "no-script-url": 2,
        // disallow comparisons where both sides are exactly the same
        "no-self-compare": 2,
        // disallow use of comma operator
        "no-sequences": 2,
        // restrict what can be thrown as an exception
        "no-throw-literal": 0,
        // disallow usage of expressions in statement position
        "no-unused-expressions": 2,
        // disallow unnecessary .call() and .apply()
        "no-useless-call": 2,
        // disallow unnecessary concatenation of literals or template literals
        "no-useless-concat": 2,
        // disallow use of void operator
        "no-void": 2,
        // disallow usage of configurable warning terms in comments: e.g. todo
        "no-warning-comments": [1, {"terms": ["todo", "fixme", "xxx"], "location": "start"}],
        // disallow use of the with statement
        "no-with": 2,
        // require use of the second argument for parseInt()
        "radix": 2,
        // requires to declare all vars on top of their containing scope
        "vars-on-top": 0,
        // require immediate function invocation to be wrapped in parentheses
        "wrap-iife": [2, "any"],
        // require or disallow Yoda conditions
        "yoda": 2,

        // //=========================================================================
        // //==================== Strict Mode ========================================
        // //=========================================================================
        // require that all functions are run in strict mode
        // "strict": [2, "global"],
        //
        //=========================================================================
        //==================== Variables ==========================================
        //=========================================================================
        // enforce or disallow variable initializations at definition
        "init-declarations": 0,
        // disallow the catch clause parameter name being the same as a variable in the outer scope
        "no-catch-shadow": 0,
        // disallow deletion of variables
        "no-delete-var": 2,
        // disallow labels that share a name with a variable
        "no-label-var": 2,
        // disallow shadowing of names such as arguments
        "no-shadow-restricted-names": 2,
        // disallow declaration of variables already declared in the outer scope
        "no-shadow": 2,
        // disallow use of undefined when initializing variables
        "no-undef-init": 0,
        // disallow use of undeclared variables unless mentioned in a /*global */ block
        "no-undef": 2,
        // disallow use of undefined variable
        "no-undefined": 0,
        // disallow declaration of variables that are not used in the code
        "no-unused-vars": [1, {"vars": "local", "args": "after-used"}],
        // disallow use of variables before they are defined
        "no-use-before-define": 2,

        //=========================================================================
        //==================== Node.js ============================================
        //=========================================================================
        // enforce return after a callback
        "callback-return": 0,
        // disallow require() outside of the top-level module scope
        "global-require": 2,
        // enforces error handling in callbacks (node environment)
        "handle-callback-err": 2,
        // disallow mixing regular variable and require declarations
        "no-mixed-requires": 2,
        // disallow use of new operator with the require function
        "no-new-require": 2,
        // disallow string concatenation with __dirname and __filename
        "no-path-concat": 1,
        // disallow process.exit()
        "no-process-exit": 2,
        // restrict usage of specified node modules
        "no-restricted-modules": 0,
        // disallow use of synchronous methods (off by default)
        "no-sync": 0,

        //=========================================================================
        //==================== Stylistic Issues ===================================
        //=========================================================================
        // enforce spacing inside array brackets
        "array-bracket-spacing": 0,
        // disallow or enforce spaces inside of single line blocks
        "block-spacing": 1,
        // enforce one true brace style
        "brace-style": [1, "1tbs", {"allowSingleLine": true}],
        // require camel case names
        "camelcase": [1, {"properties": "always"}],
        // enforce spacing before and after comma
        "comma-spacing": [1, {"before": false, "after": true}],
        // enforce one true comma style
        "comma-style": [1, "last"],
        // require or disallow padding inside computed properties
        "computed-property-spacing": 0,
        // enforces consistent naming when capturing the current execution context
        "consistent-this": 0,
        // enforce newline at the end of file, with no multiple empty lines
        "eol-last": 1,
        // require function expressions to have a name
        "func-names": 0,
        // enforces use of function declarations or expressions
        "func-style": 0,
        // this option enforces minimum and maximum identifier lengths (variable names, property names etc.)
        "id-length": 0,
        // require identifiers to match the provided regular expression
        "id-match": 0,
        // this option sets a specific tab width for your code
        "indent": [1, 4, {"SwitchCase": 1}],
        // specify whether double or single quotes should be used in JSX attributes
        "jsx-quotes": [1, "prefer-double"],
        // enforces spacing between keys and values in object literal properties
        "key-spacing": [1, {"beforeColon": false, "afterColon": true}],
        // disallow mixed "LF" and "CRLF" as linebreaks
        "linebreak-style": 0,
        // enforces empty lines around comments
        "lines-around-comment": 0,
        // specify the maximum depth that blocks can be nested
        "max-depth": [0, 4],
        // specify the maximum length of a line in your program
        "max-len": [0, 80, 4],
        // specify the maximum depth callbacks can be nested
        "max-nested-callbacks": 0,
        // limits the number of parameters that can be used in the function declaration.
        "max-params": [0, 3],
        // specify the maximum number of statement allowed in a function
        "max-statements": [0, 10],
        // require a capital letter for constructors
        "new-cap": [1, {"newIsCap": true}],
        // disallow the omission of parentheses when invoking a constructor with no arguments
        "new-parens": 0,
        // allow/disallow an empty newline after var statement
        "newline-after-var": 0,
        // disallow use of the Array constructor
        "no-array-constructor": 0,
        // disallow use of bitwise operators
        "no-bitwise": 0,
        // disallow use of the continue statement
        "no-continue": 0,
        // disallow comments inline after code
        "no-inline-comments": 0,
        // disallow if as the only statement in an else block
        "no-lonely-if": 0,
        // disallow mixed spaces and tabs for indentation
        "no-mixed-spaces-and-tabs": 1,
        // disallow multiple empty lines
        "no-multiple-empty-lines": [1, {"max": 2, "maxEOF": 1}],
        // disallow negated conditions
        "no-negated-condition": 0,
        // disallow nested ternary expressions
        "no-nested-ternary": 1,
        // disallow use of the Object constructor
        "no-new-object": 1,
        // disallow use of unary operators, ++ and --
        "no-plusplus": 0,
        // disallow use of certain syntax in code
        "no-restricted-syntax": 0,
        // disallow space between function identifier and application
        "no-spaced-func": 1,
        // disallow the use of ternary operators
        "no-ternary": 0,
        // disallow trailing whitespace at the end of lines
        "no-trailing-spaces": 1,
        // disallow dangling underscores in identifiers
        "no-underscore-dangle": 0,
        // disallow the use of Boolean literals in conditional expressions
        "no-unneeded-ternary": 0,
        // require or disallow padding inside curly braces
        "object-curly-spacing": 0,
        // allow just one var statement per function
        "one-var": [1, "never"],
        // require assignment operator shorthand where possible or prohibit it entirely
        "operator-assignment": 0,
        // enforce operators to be placed before or after line breaks
        "operator-linebreak": 0,
        // enforce padding within blocks
        "padded-blocks": [1, "never"],
        // require quotes around object literal property names
        "quote-props": 0,
        // specify whether double or single quotes should be used
        "quotes": [1, "single", "avoid-escape"],
        // Require JSDoc comment
        "require-jsdoc": 0,
        // enforce spacing before and after semicolons
        "semi-spacing": [1, {"before": false, "after": true}],
        // require or disallow use of semicolons instead of ASI
        "semi": [1, "always"],
        // sort variables within the same declaration block
        "sort-vars": 0,
        // require a space after certain keywords
        "keyword-spacing": 1,
        // require or disallow space before blocks
        "space-before-blocks": 1,
        // require or disallow space before function opening parenthesis
        "space-before-function-paren": [0, {"anonymous": "always", "named": "never"}],
        // require or disallow space before blocks
        "space-in-parens": 0,
        // require spaces around operators
        "space-infix-ops": 1,
        // Require or disallow spaces before/after unary operators
        "space-unary-ops": 0,
        // require or disallow a space immediately following the // or /* in a comment
        "spaced-comment": [1, "always", {
            "exceptions": ["-", "+", "/", "="],
            "markers": ["=", "!", "/"]     // space here to support sprockets directives
        }],
        // require regex literals to be wrapped in parentheses
        "wrap-regex": 0,

        //=========================================================================
        //==================== ES6 Rules ==========================================
        //=========================================================================
        "arrow-body-style": [1, "as-needed"],
        // require parens in arrow function arguments
        "arrow-parens": [1, "as-needed"],
        // require space before/after arrow function"s arrow
        "arrow-spacing": 1,
        // verify super() callings in constructors
        "constructor-super": 1,
        // enforce the spacing around the * in generator functions
        "generator-star-spacing": 1,
        // disallow arrow functions where a condition is expected
        "no-confusing-arrow": 1,
        // disallow modifying variables of class declarations
        "no-class-assign": 1,
        // disallow modifying variables that are declared using const
        "no-const-assign": 1,
        // disallow duplicate name in class members
        "no-dupe-class-members": 1,
        // disallow to use this/super before super() calling in constructors.
        "no-this-before-super": 1,
        // require let or const instead of var
        "no-var": 0, //TODO: enable on full migration to es6
        // require method and property shorthand syntax for object literals
        "object-shorthand": 0,
        // suggest using arrow functions as callbacks
        "prefer-arrow-callback": 0, //TODO: enable on full migration to es6
        // suggest using of const declaration for variables that are never modified after declared
        "prefer-const": 0, //TODO: enable on full migration to es6
        // suggest using Reflect methods where applicable
        "prefer-reflect": 0,
        // suggest using the spread operator instead of .apply()
        "prefer-spread": 0,
        // suggest using template literals instead of strings concatenation
        "prefer-template": 0, //TODO: enable on full migration to es6
        // disallow generator functions that do not have yield
        "require-yield": 0
    }
}