.eslintrc.json

//-*- js-indent-level: 2 -*-
// Inspired by JavaScript Whatever Style (https://github.com/junosuarez/jsw)
{
  "env": {
    "browser": true,
    "es6": true
  },
  "extends": "eslint:recommended",
  "parserOptions": {
    "ecmaVersion": 2015
  },
  // Rules taken from: https://standardjs.com/rules.html (except OWN rules).
  "rules": {
    // OWN: Require fat arrow with implicit return to be on one line.
    "implicit-arrow-linebreak": "error",
    // OWN: Prefer spread func([...x]) over func.apply(x). (on/off)
    "prefer-spread": "error",
    // OWN: Require strict mode.
    "strict": "error",
    // OWN: Use Unix line breaks.
    "linebreak-style": ["error", "unix"],
    // Use 2 spaces for indentation. (has opts)
    // NOTE: Eslint fails to check indent after newline in expr like 'a\n+ b'.
    "indent": ["error", 2],
    // Use single quotes for strings except to avoid escaping.
    "quotes": ["error", "single", {
      "avoidEscape": true
    }],
    // No unused variables (except '_').
    "no-unused-vars": ["error", {
      "varsIgnorePattern": "^_$"
    }],
    // Add a space after keywords.
    "keyword-spacing": "error",
    // Add a space before a function declaration's parentheses.
    "space-before-function-paren": ["error", {
      "anonymous": "always",
      "asyncArrow": "always",
      "named": "never"
    }],
    // Always use `===` instead of `==`.<br>
    "eqeqeq": ["error", "always"],
    // Infix operators must be spaced.
    "space-infix-ops": "error",
    // Commas should have a space after them.
    "comma-spacing": "error",
    // Keep else statements on the same line as their curly braces.
    "brace-style": ["error", "1tbs", { "allowSingleLine": true }],
    // For multi-line if statements, use curly braces.
    "curly": "error",
    // Always handle the `err` function parameter.
    "handle-callback-err": "error",
    // Declare browser globals with a `/* global */` comment.
    // FIXME ??
    // Multiple blank lines not allowed.
    "no-multiple-empty-lines": ["error", {
      "max": 1,
      "maxBOF": 0,
      "maxEOF": 0
    }],
    // OWN: +, ?:, etc should come at beginning of next line if linebreaked.
    // (Cuts down on reliance of 'no-unexpected-multiline' for '('.)
    "operator-linebreak": ["error", "before"],
    // For var declarations, write each declaration in its own statement.
    "one-var": ["error", "never"],
    // Wrap conditional assignments with additional parentheses.
    "no-cond-assign": "error",
    // Add spaces inside single line blocks.
    "block-spacing": "error",
    // Use camelcase when naming variables and functions.
    "camelcase" : "error",
    // Trailing commas not allowed. (OWN: jsw disallow this, I require them.)
    "comma-dangle": ["error", "always-multiline", {
        "functions": "never"
    }],
    // Commas must be placed at the end of the current line.
    "comma-style": "error",
    // Dot should be on the same line as property.
    "dot-location": ["error", "property"],
    // Files must end with a newline.
    "eol-last": ["error", "always"],
    // No space between function identifiers and their invocations.
    "func-call-spacing": "error",
    // In key/value pairs, require zero space before colon, and one or more after.
    "key-spacing": ["error", {
      "beforeColon": false,
      "afterColon": true,
      "mode": "minimum"
    }],
    // Constructor names must begin with a capital letter.
    "new-cap": "error",
    // Constructor with no arguments must be invoked with parentheses.
    "new-parens": "error",
    // Objects must contain a getter when a setter is defined.
    "accessor-pairs": "error",
    // Constructors of derived classes must call `super`.
    "constructor-super": "error",
    // Use array literals instead of array constructors.
    "no-array-constructor": "error",
    // Avoid using `arguments.callee` and `arguments.caller`.
    "no-caller": "error",
    // Avoid modifying variables of class declarations.
    "no-class-assign": "error",
    // Avoid modifying variables declared using `const`.
    "no-const-assign": "error",
    // Avoid using constant expressions in conditions (except loops).
    "no-constant-condition": "error",
    // No control characters in regular expressions.
    "no-control-regex": "error",
    // No `debugger` statements.
    "no-debugger": "error",
    // No `delete` operator on variables.
    "no-delete-var": "error",
    // No duplicate arguments in function definitions.
    "no-dupe-args": "error",
    // No duplicate name in class members.
    "no-dupe-class-members": "error",
    // No duplicate keys in object literals.
    "no-dupe-keys": "error",
    // No duplicate `case` labels in `switch` statements.
    "no-duplicate-case": "error",
    // Use a single import statement per module.
    "no-duplicate-imports": "error",
    // No empty character classes in regular expressions.
    "no-empty-character-class": "error",
    // No empty destructuring patterns.
    "no-empty-pattern": "error",
    // No using `eval()`.
    "no-eval": "error",
    // No reassigning exceptions in `catch` clauses.
    "no-ex-assign": "error",
    // No extending native objects.
    "no-extend-native": "error",
    // Avoid unnecessary function binding.
    "no-extra-bind": "error",
    // Avoid unnecessary boolean casts.
    "no-extra-boolean-cast": "error",
    // No unnecessary parentheses around function expressions.
    "no-extra-parens": ["error", "functions"],
    // Use `break` to prevent fallthrough in `switch` cases.
    "no-fallthrough": "error",
    // OWN: Require space after colon in `switch` statement.
    "switch-colon-spacing": "error",
    // No floating decimals.
    "no-floating-decimal": "error",
    // Avoid reassigning function declarations.
    "no-func-assign": "error",
    // No reassigning read-only global variables.
    "no-global-assign": "error",
    // No implied `eval()`.
    "no-implied-eval": "error",
    // No function declarations in nested blocks.
    "no-inner-declarations": "error",
    // No invalid regular expression strings in  `RegExp` constructors.
    "no-invalid-regexp": "error",
    // No irregular whitespace.
    "no-irregular-whitespace": "error",
    // No using `__iterator__`.
    "no-iterator": "error",
    // No labels that share a name with an in scope variable.
    "no-label-var": "error",
    // No label statements.
    "no-labels": "error",
    // No unnecessary nested blocks.
    "no-lone-blocks": "error",
    // Avoid mixing spaces and tabs for indentation.
    "no-mixed-spaces-and-tabs": "error",
    // Do not use multiple spaces except for indentation.
    "no-multi-spaces": ["error", {
      "ignoreEOLComments": true
    }],
    // No multiline strings.
    "no-multi-str": "error",
    // No `new` without assigning object to a variable.
    "no-new": "error",
    // No using the `Function` constructor.
    "no-new-func": "error",
    // No using the `Object` constructor.
    "no-new-object": "error",
    // No using `new require`.
    "no-new-require": "error",
    // No using the `Symbol` constructor.
    "no-new-symbol": "error",
    // No using primitive wrapper instances.
    "no-new-wrappers": "error",
    // No calling global object properties as functions.
    "no-obj-calls": "error",
    // No octal literals. (on/off)
    "no-octal": "error",
    // No octal escape sequences in string literals. (on/off)
    "no-octal-escape": "error",
    // Avoid string concatenation when using `__dirname` and `__filename`. (on/off)
    "no-path-concat": "error",
    // Avoid using `__proto__`. Use `getPrototypeOf` instead. (on/off)
    "no-proto": "error",
    // No redeclaring variables. (has opts)
    "no-redeclare": "error",
    // Avoid multiple spaces in regular expression literals. (on/off)
    "no-regex-spaces": "error",
    // Assignments in return statements must be surrounded by parentheses. (has opts)
    "no-return-assign": "error",
    // Avoid assigning a variable to itself
    "no-self-assign": ["error", {
      "props": true
    }],
    // Avoid comparing a variable to itself.
    "no-self-compare": "error",
    // Avoid using the comma operator. (has opts)
    "no-sequences": "error",
    // Restricted names should not be shadowed. (on/off)
    "no-shadow-restricted-names": "error",
    // Sparse arrays are not allowed. (on/off)
    "no-sparse-arrays": "error",
    // Tabs should not be used. (has opts)
    "no-tabs": "error",
    // Regular strings must not contain template literal placeholders. (on/off)
    "no-template-curly-in-string": "error",
    // `super()` must be called before using `this`. (on/off)
    "no-this-before-super": "error",
    // Only `throw` an `Error` object. (on/off)
    "no-throw-literal": "error",
    // Whitespace not allowed at end of line.
    "no-trailing-spaces": "error",
    // Initializing to `undefined` is not allowed.
    "no-undef-init": "error",
    // No unmodified conditions of loops. (on/off)
    "no-unmodified-loop-condition": "error",
    // No ternary operators when simpler alternatives exist. (has opts)
    "no-unneeded-ternary": "error",
    // No unreachable code after `return`, `throw`, `continue`, and `break` statements. (on/off)
    "no-unreachable": "error",
    // No flow control statements in `finally` blocks. (on/off)
    "no-unsafe-finally": "error",
    // The left operand of relational operators must not be negated. (has opts)
    "no-unsafe-negation": "error",
    // Avoid unnecessary use of `.call()` and `.apply()`. (on/off)
    "no-useless-call": "error",
    // Avoid using unnecessary computed property keys on objects. (has opts)
    "no-useless-computed-key": "error",
    // No unnecessary constructor. (on/off)
    "no-useless-constructor": "error",
    // No unnecessary use of escape. (on/off)
    "no-useless-escape": "error",
    // Renaming import, export, and destructured assignments to the same name is not allowed. (has opts)
    "no-useless-rename": "error",
    // No whitespace before properties. (on/off)
    "no-whitespace-before-property": "error",
    // No using `with` statements. (on/off)
    "no-with": "error",
    // Maintain consistency of newlines between object properties. (has opts)
    "object-property-newline": ["error", {
      "allowAllPropertiesOnSameLine": true
    }],
    // No padding within blocks. (has opts)
    "padded-blocks": ["error", "never"],
    // No whitespace between spread operators and their expressions.
    "rest-spread-spacing": "error",
    // Semicolons must have a space after and no space before. (has opts)
    "semi-spacing": "error",
    // Must have a space before blocks. (has opts)
    "space-before-blocks": "error",
    // No spaces inside parentheses. (has opts)
    "space-in-parens": "error",
    // OWN: No spaces inside brackets (in array listing).
    "array-bracket-spacing": "error",
    // OWN: No spaces inside brackets (in computed propetry).
    "computed-property-spacing": ["error", "never"],
    // Unary operators must have a space after. (has opts)
    "space-unary-ops": "error",
    // Use spaces inside comments. (has opts)
    "spaced-comment": ["error", "always", {
      "block": {
        "exceptions": ["*", "[eof]"],
        "balanced": true
      },
      "line": {
        "exceptions": ["/", "[eof]"]
      }
    }],
    // No spacing in template strings. (on/off)
    "template-curly-spacing": "error",
    // Use `isNaN()` when checking for `NaN`. (has opts)
    "use-isnan": "error",
    // `typeof` must be compared to a valid string. (has opts)
    "valid-typeof": "error",
    // Immediately Invoked Function Expressions (IIFEs) must be wrapped. (has opts)
    "wrap-iife": "error",
    // The `*` in `yield*`expressions must have a space before and after. (has opts)
    "yield-star-spacing": "error",
    // Avoid Yoda conditions. (has opts)
    "yoda": "error",
    // No semicolons. (has opts)
    "semi": ["error", "never"],
    // Never start a line with `(`, `[`, '`', or a handful of other unlikely possibilities. (on/off)
    "no-unexpected-multiline": "error",

    /*======================================================================*/
    // FIXME: OWN stuff
    "dot-notation": ["error", { "allowKeywords": true }],
    "lines-between-class-members": ["error", "never", {
        "exceptAfterSingleLine": true
    }],
    "no-case-declarations": "error",
    "no-empty": ["error", {
        "allowEmptyCatch": true
    }],
    // "no-shadow": "error", // FIXME: use this
    "no-void": "error",
    // OWN: Disallow 'var' declarations. (on/off)
    "no-var": "error",
    "object-curly-newline": ["error", {
      "multiline": true,
      "consistent": true
    }],
    "object-curly-spacing": ["error", "always"]
  }
}
//[eof]