options.js

"use strict";

// These are the JSHint boolean options.
exports.bool = {
  enforcing: {

    /**
     * This option prohibits the use of bitwise operators such as `^` (XOR),
     * `|` (OR) and others. Bitwise operators are very rare in JavaScript
     * programs and quite often `&` is simply a mistyped `&&`.
     */
    bitwise     : true,

    /**
     *
     * This options prohibits overwriting prototypes of native objects such as
     * `Array`, `Date` and so on.
     *
     *     // jshint freeze:true
     *     Array.prototype.count = function (value) { return 4; };
     *     // -> Warning: Extending prototype of native object: 'Array'.
     */
    freeze      : true,

    /**
     * This option allows you to force all variable names to use either
     * camelCase style or UPPER_CASE with underscores.
     *
     * @deprecated JSHint is limiting its scope to issues of code correctness.
     *             If you would like to enforce rules relating to code style,
     *             check out [the JSCS
     *             project](https://github.com/jscs-dev/node-jscs).
     */
    camelcase   : true,

    /**
     * This option requires you to always put curly braces around blocks in
     * loops and conditionals. JavaScript allows you to omit curly braces when
     * the block consists of only one statement, for example:
     *
     *     while (day)
     *       shuffle();
     *
     * However, in some circumstances, it can lead to bugs (you'd think that
     * `sleep()` is a part of the loop while in reality it is not):
     *
     *     while (day)
     *       shuffle();
     *       sleep();
     */
    curly       : true,

    /**
     * This options prohibits the use of `==` and `!=` in favor of `===` and
     * `!==`. The former try to coerce values before comparing them which can
     * lead to some unexpected results. The latter don't do any coercion so
     * they are generally safer. If you would like to learn more about type
     * coercion in JavaScript, we recommend [Truth, Equality and
     * JavaScript](http://javascriptweblog.wordpress.com/2011/02/07/truth-equality-and-javascript/)
     * by Angus Croll.
     */
    eqeqeq      : true,

    /**
     * This option enables warnings about the use of identifiers which are
     * defined in future versions of JavaScript. Although overwriting them has
     * no effect in contexts where they are not implemented, this practice can
     * cause issues when migrating codebases to newer versions of the language.
     */
    futurehostile: true,

    /**
     * This option tells JSHint that your code needs to adhere to ECMAScript 3
     * specification. Use this option if you need your program to be executable
     * in older browsers—such as Internet Explorer 6/7/8/9—and other legacy
     * JavaScript environments.
     *
     * @deprecated Use `esversion: 3` instead.
     */
    es3         : true,

    /**
     * This option enables syntax first defined in [the ECMAScript 5.1
     * specification](http://es5.github.io/). This includes allowing reserved
     * keywords as object properties.
     *
     * @deprecated Use `esversion: 5` instead.
     */
    es5         : true,

    /**
     * This option requires all `for in` loops to filter object's items. The
     * for in statement allows for looping through the names of all of the
     * properties of an object including those inherited through the prototype
     * chain. This behavior can lead to unexpected items in your object so it
     * is generally safer to always filter inherited properties out as shown in
     * the example:
     *
     *     for (key in obj) {
     *       if (obj.hasOwnProperty(key)) {
     *         // We are sure that obj[key] belongs to the object and was not inherited.
     *       }
     *     }
     *
     * For more in-depth understanding of `for in` loops in JavaScript, read
     * [Exploring JavaScript for-in
     * loops](http://javascriptweblog.wordpress.com/2011/01/04/exploring-javascript-for-in-loops/)
     * by Angus Croll.
     */
    forin       : true,

    /**
     * This option prohibits the use of immediate function invocations without
     * wrapping them in parentheses. Wrapping parentheses assists readers of
     * your code in understanding that the expression is the result of a
     * function, and not the function itself.
     *
     * @deprecated JSHint is limiting its scope to issues of code correctness.
     *             If you would like to enforce rules relating to code style,
     *             check out [the JSCS
     *             project](https://github.com/jscs-dev/node-jscs).
     */
    immed       : true,

    /**
     * This option prohibits unnecessary clauses within `switch` statements,
     * e.g.
     *
     *     switch (x) {
     *       case 1:
     *       default:
     *         z();
     *     }
     *
     * While clauses like these are techincally valid, they do not effect
     * program behavior and may indicate an erroneous refactoring.
     */
    leanswitch  : true,

    /**
     * This option requires you to capitalize names of constructor functions.
     * Capitalizing functions that are intended to be used with `new` operator
     * is just a convention that helps programmers to visually distinguish
     * constructor functions from other types of functions to help spot
     * mistakes when using `this`.
     *
     * Not doing so won't break your code in any browsers or environments but
     * it will be a bit harder to figure out—by reading the code—if the
     * function was supposed to be used with or without new. And this is
     * important because when the function that was intended to be used with
     * `new` is used without it, `this` will point to the global object instead
     * of a new object.
     *
     * @deprecated JSHint is limiting its scope to issues of code correctness.
     *             If you would like to enforce rules relating to code style,
     *             check out [the JSCS
     *             project](https://github.com/jscs-dev/node-jscs).
     */
    newcap      : true,

    /**
     * This option prohibits the use of `arguments.caller` and
     * `arguments.callee`.  Both `.caller` and `.callee` make quite a few
     * optimizations impossible so they were deprecated in future versions of
     * JavaScript. In fact, ECMAScript 5 forbids the use of `arguments.callee`
     * in strict mode.
     */
    noarg       : true,

    /**
     * This option prohibits the use of the comma operator. When misused, the
     * comma operator can obscure the value of a statement and promote
     * incorrect code.
     */
    nocomma     : true,

    /**
     * This option warns when you have an empty block in your code. JSLint was
     * originally warning for all empty blocks and we simply made it optional.
     * There were no studies reporting that empty blocks in JavaScript break
     * your code in any way.
     *
     * @deprecated JSHint is limiting its scope to issues of code correctness.
     *             If you would like to enforce rules relating to code style,
     *             check out [the JSCS
     *             project](https://github.com/jscs-dev/node-jscs).
     */
    noempty     : true,

    /**
     * This option warns about "non-breaking whitespace" characters. These
     * characters can be entered with option-space on Mac computers and have a
     * potential of breaking non-UTF8 web pages.
     */
    nonbsp      : true,

    /**
     * This option prohibits the use of constructor functions for side-effects.
     * Some people like to call constructor functions without assigning its
     * result to any variable:
     *
     *     new MyConstructor();
     *
     * There is no advantage in this approach over simply calling
     * `MyConstructor` since the object that the operator `new` creates isn't
     * used anywhere so you should generally avoid constructors like this one.
     */
    nonew       : true,


    /**
     * Async functions resolve on their return value. In most cases, this makes
     * returning the result of an AwaitExpression (which is itself a Promise
     * instance) unnecessary. For clarity, it's often preferable to return the
     * result of the asynchronous operation directly. The notable exception is
     * within the `try` clause of a TryStatement--for more, see "await vs
     * return vs return await":
     *
     * https://jakearchibald.com/2017/await-vs-return-vs-return-await/
     */
    noreturnawait: true,

    /**
     * This option enables warnings for regular expressions which do not
     * include the "u" flag. The "u" flag extends support for Unicode and also
     * enables more strict parsing rules. JSHint will enforce these rules even
     * if it is executed in a JavaScript engine which does not support the "u"
     * flag.
     */
    regexpu     : true,

    /**
     * This option prohibits the use of explicitly undeclared variables. This
     * option is very useful for spotting leaking and mistyped variables.
     *
     *     // jshint undef:true
     *
     *     function test() {
     *       var myVar = 'Hello, World';
     *       console.log(myvar); // Oops, typoed here. JSHint with undef will complain
     *     }
     *
     * If your variable is defined in another file, you can use the `global`
     * directive to tell JSHint about it.
     */
    undef       : true,

    /**
     * This option prohibits the use of the grouping operator when it is not
     * strictly required. Such usage commonly reflects a misunderstanding of
     * unary operators, for example:
     *
     *     // jshint singleGroups: true
     *
     *     delete(obj.attr); // Warning: Unnecessary grouping operator.
     */
    singleGroups: false,

    /**
     * When set to true, the use of VariableStatements are forbidden.
     * For example:
     *
     *     // jshint varstmt: true
     *
     *     var a; // Warning: `var` declarations are forbidden. Use `let` or `const` instead.
     */
    varstmt: false,

    /**
     * This option is a short hand for the most strict JSHint configuration as
     * available in JSHint version 2.6.3. It enables all enforcing options and
     * disables all relaxing options that were defined in that release.
     *
     * @deprecated The option cannot be maintained without automatically opting
     *             users in to new features. This can lead to unexpected
     *             warnings/errors in when upgrading between minor versions of
     *             JSHint.
     */
    enforceall : false,

    /**
     * This option warns when a comma is not placed after the last element in an
     * array or object literal. Due to bugs in old versions of IE, trailing
     * commas used to be discouraged, but since ES5 their semantics were
     * standardized. (See
     * [#11.1.4](http://www.ecma-international.org/ecma-262/5.1/#sec-11.1.4) and
     * [#11.1.5](http://www.ecma-international.org/ecma-262/5.1/#sec-11.1.5).)
     * Now, they help to prevent the same [visual
     * ambiguities](http://www.ecma-international.org/ecma-262/5.1/#sec-7.9.2)
     * that the strict usage of semicolons helps prevent.
     *
     * For example, this code might have worked last Tuesday:
     *
     *     [
     *         b + c
     *     ].forEach(print);
     *
     * But if one adds an element to the array and forgets to compensate for the
     * missing comma, no syntax error is thrown, and a linter cannot determine
     * if this was a mistake or an intentional function invocation.
     *
     *     [
     *         b + c
     *         (d + e)
     *     ].forEach(print);
     *
     * If one always appends a list item with a comma, this ambiguity cannot
     * occur:
     *
     *     [
     *         b + c,
     *     ].forEach(print);
     *
     *     [
     *         b + c,
     *         (d + e),
     *     ].forEach(print);
     */
    trailingcomma: false
  },
  relaxing: {

    /**
     * This option suppresses warnings about missing semicolons. There is a lot
     * of FUD about semicolon spread by quite a few people in the community.
     * The common myths are that semicolons are required all the time (they are
     * not) and that they are unreliable. JavaScript has rules about semicolons
     * which are followed by *all* browsers so it is up to you to decide
     * whether you should or should not use semicolons in your code.
     *
     * For more information about semicolons in JavaScript read [An Open Letter
     * to JavaScript Leaders Regarding
     * Semicolons](http://blog.izs.me/post/2353458699/an-open-letter-to-javascript-leaders-regarding)
     * by Isaac Schlueter and [JavaScript Semicolon
     * Insertion](http://inimino.org/~inimino/blog/javascript_semicolons).
     */
    asi         : true,

    /**
     * This option suppresses warnings about multi-line strings. Multi-line
     * strings can be dangerous in JavaScript because all hell breaks loose if
     * you accidentally put a whitespace in between the escape character (`\`)
     * and a new line.
     *
     * Note that even though this option allows correct multi-line strings, it
     * still warns about multi-line strings without escape characters or with
     * anything in between the escape character and a whitespace.
     *
     *     // jshint multistr:true
     *
     *     var text = "Hello\
     *     World"; // All good.
     *
     *     text = "Hello
     *     World"; // Warning, no escape character.
     *
     *     text = "Hello\
     *     World"; // Warning, there is a space after \
     *
     * @deprecated JSHint is limiting its scope to issues of code correctness.
     *             If you would like to enforce rules relating to code style,
     *             check out [the JSCS
     *             project](https://github.com/jscs-dev/node-jscs).
     */
    multistr    : true,

    /**
     * This option suppresses warnings about the `debugger` statements in your
     * code.
     */
    debug       : true,

    /**
     * This option suppresses warnings about the use of assignments in cases
     * where comparisons are expected. More often than not, code like `if (a =
     * 10) {}` is a typo. However, it can be useful in cases like this one:
     *
     *     for (var i = 0, person; person = people[i]; i++) {}
     *
     * You can silence this error on a per-use basis by surrounding the assignment
     * with parenthesis, such as:
     *
     *     for (var i = 0, person; (person = people[i]); i++) {}
     */
    boss        : true,

    /**
     * This option suppresses warnings about the use of `eval`. The use of
     * `eval` is discouraged because it can make your code vulnerable to
     * various injection attacks and it makes it hard for JavaScript
     * interpreter to do certain optimizations.
    */
    evil        : true,

    /**
     * This option suppresses warnings about declaring variables inside
     * of control structures while accessing them later from the outside.
     * Even though identifiers declared with `var` have two real scopes—global
     * and function—such practice leads to confusion among people new to
     * the language and hard-to-debug bugs. This is why, by default, JSHint
     * warns about variables that are used outside of their intended scope.
     *
     *     function test() {
     *       if (true) {
     *         var x = 0;
     *       }
     *
     *       x += 1; // Default: 'x' used out of scope.
     *                 // No warning when funcscope:true
     *     }
     */
    funcscope   : true,

    /**
     * This option suppresses warnings about the use of global strict mode.
     * Global strict mode can break third-party widgets so it is not
     * recommended.
     *
     * For more info about strict mode see the `strict` option.
     *
     * @deprecated Use `strict: "global"`.
     */
    globalstrict: true,

    /**
     * This option suppresses warnings about the `__iterator__` property. This
     * property is not supported by all browsers so use it carefully.
     */
    iterator    : true,

     /**
     * This option suppresses warnings about invalid `typeof` operator values.
     * This operator has only [a limited set of possible return
     * values](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/typeof).
     * By default, JSHint warns when you compare its result with an invalid
     * value which often can be a typo.
     *
     *     // 'fuction' instead of 'function'
     *     if (typeof a == "fuction") { // Invalid typeof value 'fuction'
     *       // ...
     *     }
     *
     * Do not use this option unless you're absolutely sure you don't want
     * these checks.
     */
    notypeof    : true,

    /**
     * This option prohibits the use of unary increment and decrement
     * operators.  Some people think that `++` and `--` reduces the quality of
     * their coding styles and there are programming languages—such as
     * Python—that go completely without these operators.
     */
    plusplus    : true,

    /**
     * This option suppresses warnings about the `__proto__` property.
     */
    proto       : true,

    /**
     * This option suppresses warnings about the use of script-targeted
     * URLs—such as `javascript:...`.
     */
    scripturl   : true,

    /**
     * This option suppresses warnings about using `[]` notation when it can be
     * expressed in dot notation: `person['name']` vs. `person.name`.
     *
     * @deprecated JSHint is limiting its scope to issues of code correctness.
     *             If you would like to enforce rules relating to code style,
     *             check out [the JSCS
     *             project](https://github.com/jscs-dev/node-jscs).
     */
    sub         : true,

    /**
     * This option suppresses warnings about "weird" constructions like
     * `new function () { ... }` and `new Object;`. Such constructions are
     * sometimes used to produce singletons in JavaScript:
     *
     *     var singleton = new function() {
     *       var privateVar;
     *
     *       this.publicMethod  = function () {}
     *       this.publicMethod2 = function () {}
     *     };
     */
    supernew    : true,

    /**
     * This option suppresses most of the warnings about possibly unsafe line
     * breakings in your code. It doesn't suppress warnings about comma-first
     * coding style. To suppress those you have to use `laxcomma` (see below).
     *
     * @deprecated JSHint is limiting its scope to issues of code correctness.
     *             If you would like to enforce rules relating to code style,
     *             check out [the JSCS
     *             project](https://github.com/jscs-dev/node-jscs).
     */
    laxbreak    : true,

    /**
     * This option suppresses warnings about comma-first coding style:
     *
     *     var obj = {
     *         name: 'Anton'
     *       , handle: 'valueof'
     *       , role: 'SW Engineer'
     *     };
     *
     * @deprecated JSHint is limiting its scope to issues of code correctness.
     *             If you would like to enforce rules relating to code style,
     *             check out [the JSCS
     *             project](https://github.com/jscs-dev/node-jscs).
     */
    laxcomma    : true,

    /**
     * This option suppresses warnings about possible strict violations when
     * the code is running in strict mode and you use `this` in a
     * non-constructor function. You should use this option—in a function scope
     * only—when you are positive that your use of `this` is valid in the
     * strict mode (for example, if you call your function using
     * `Function.call`).
     *
     * **Note:** This option can be used only inside of a function scope.
     * JSHint will fail with an error if you will try to set this option
     * globally.
     */
    validthis   : true,

    /**
     * This option suppresses warnings about the use of the `with` statement.
     * The semantics of the `with` statement can cause confusion among
     * developers and accidental definition of global variables.
     *
     * More info:
     *
     * * [with Statement Considered
     *   Harmful](http://yuiblog.com/blog/2006/04/11/with-statement-considered-harmful/)
     */
    withstmt    : true,

    /**
     * This options tells JSHint that your code uses Mozilla JavaScript
     * extensions. Unless you develop specifically for the Firefox web browser
     * you don't need this option.
     *
     * More info:
     *
     * * [New in JavaScript
     *   1.7](https://developer.mozilla.org/en-US/docs/JavaScript/New_in_JavaScript/1.7)
     */
    moz         : true,

    /**
     * This option suppresses warnings about generator functions with no
     * `yield` statement in them.
     */
    noyield     : true,

    /**
     * This option suppresses warnings about `== null` comparisons. Such
     * comparisons are often useful when you want to check if a variable is
     * `null` or `undefined`.
     */
    eqnull      : true,

    /**
     * This option suppresses warnings about missing semicolons, but only when
     * the semicolon is omitted for the last statement in a one-line block:
     *
     *     var name = (function() { return 'Anton' }());
     *
     * This is a very niche use case that is useful only when you use automatic
     * JavaScript code generators.
     */
    lastsemic   : true,

    /**
     * This option suppresses warnings about functions inside of loops.
     * Defining functions inside of loops can lead to bugs such as this one:
     *
     *     var nums = [];
     *
     *     for (var i = 0; i < 10; i++) {
     *       nums[i] = function (j) {
     *         return i + j;
     *       };
     *     }
     *
     *     nums[0](2); // Prints 12 instead of 2
     *
     * To fix the code above you need to copy the value of `i`:
     *
     *     var nums = [];
     *
     *     for (var i = 0; i < 10; i++) {
     *       (function (i) {
     *         nums[i] = function (j) {
     *             return i + j;
     *         };
     *       }(i));
     *     }
     */
    loopfunc    : true,

    /**
     * This option suppresses warnings about the use of expressions where
     * normally you would expect to see assignments or function calls. Most of
     * the time, such code is a typo. However, it is not forbidden by the spec
     * and that's why this warning is optional.
     */
    expr        : true,

    /**
     * This option tells JSHint that your code uses ECMAScript 6 specific
     * syntax. Note that not all browsers implement these features.
     *
     * More info:
     *
     * * [Specification for ECMAScript
     *   6](http://www.ecma-international.org/ecma-262/6.0/index.html)
     *
     * @deprecated Use `esversion: 6` instead.
     */
    esnext      : true,

    /**
     * This option tells JSHint that your code uses ES3 array elision elements,
     * or empty elements (for example, `[1, , , 4, , , 7]`).
     */
    elision     : true,
  },

  // Third party globals
  environments: {

    /**
     * This option defines globals exposed by the
     * [MooTools](http://mootools.net/) JavaScript framework.
     */
    mootools    : true,

    /**
     * This option defines globals exposed by
     * [CouchDB](http://couchdb.apache.org/). CouchDB is a document-oriented
     * database that can be queried and indexed in a MapReduce fashion using
     * JavaScript.
     */
    couch       : true,

    /**
     * This option defines globals exposed by [the Jasmine unit testing
     * framework](https://jasmine.github.io/).
     */
    jasmine     : true,

    /**
     * This option defines globals exposed by the [jQuery](http://jquery.com/)
     * JavaScript library.
     */
    jquery      : true,

    /**
     * This option defines globals available when your code is running inside
     * of the Node runtime environment. [Node.js](http://nodejs.org/) is a
     * server-side JavaScript environment that uses an asynchronous
     * event-driven model. This option also skips some warnings that make sense
     * in the browser environments but don't make sense in Node such as
     * file-level `use strict` pragmas and `console.log` statements.
     */
    node        : true,

    /**
     * This option defines globals exposed by [the QUnit unit testing
     * framework](http://qunitjs.com/).
     */
    qunit       : true,

    /**
     * This option defines globals available when your code is running inside
     * of the Rhino runtime environment. [Rhino](http://www.mozilla.org/rhino/)
     * is an open-source implementation of JavaScript written entirely in Java.
     */
    rhino       : true,

    /**
     * This option defines globals exposed by [the ShellJS
     * library](http://documentup.com/arturadib/shelljs).
     */
    shelljs     : true,

    /**
     * This option defines globals exposed by the
     * [Prototype](http://www.prototypejs.org/) JavaScript framework.
     */
    prototypejs : true,

    /**
     * This option defines globals exposed by the [YUI](http://yuilibrary.com/)
     * JavaScript framework.
     */
    yui         : true,

    /**
     * This option defines globals exposed by the "BDD" and "TDD" UIs of the
     * [Mocha unit testing framework](http://mochajs.org/).
     */
    mocha       : true,

    /**
     * This option informs JSHint that the input code describes an ECMAScript 6
     * module. All module code is interpreted as strict mode code.
     */
    module      : true,

    /**
     * This option defines globals available when your code is running as a
     * script for the [Windows Script
     * Host](http://en.wikipedia.org/wiki/Windows_Script_Host).
     */
    wsh         : true,

    /**
     * This option defines globals available when your code is running inside
     * of a Web Worker. [Web
     * Workers](https://developer.mozilla.org/en/Using_web_workers) provide a
     * simple means for web content to run scripts in background threads.
     */
    worker      : true,

    /**
     * This option defines non-standard but widely adopted globals such as
     * `escape` and `unescape`.
     */
    nonstandard : true,

    /**
     * This option defines globals exposed by modern browsers: all the way from
     * good old `document` and `navigator` to the HTML5 `FileReader` and other
     * new developments in the browser world.
     *
     * **Note:** This option doesn't expose variables like `alert` or
     * `console`. See option `devel` for more information.
     */
    browser     : true,

    /**
     * This option defines globals available when using [the Browserify
     * tool](http://browserify.org/) to build a project.
     */
    browserify  : true,

    /**
     * This option defines globals that are usually used for logging poor-man's
     * debugging: `console`, `alert`, etc. It is usually a good idea to not
     * ship them in production because, for example, `console.log` breaks in
     * legacy versions of Internet Explorer.
     */
    devel       : true,

    /**
     * This option defines globals exposed by the [Dojo
     * Toolkit](http://dojotoolkit.org/).
     */
    dojo        : true,

    /**
     * This option defines globals for typed array constructors.
     *
     * More info:
     *
     * * [JavaScript typed
     *   arrays](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Typed_arrays)
     */
    typed       : true,

    /**
     * This option defines globals available when your core is running inside
     * of the Chrome runtime environment. [Chrome](http://chromium.org/)
     * is a headless WebKit scriptable with a JavaScript API. It has fast and
     * native support for various web standards: DOM handling, CSS selector,
     * JSON, Canvas, and SVG.
     */
    chrome     : true
  },

  // Obsolete options
  obsolete: {
    onecase     : true, // if one case switch statements should be allowed
    regexp      : true, // if the . should not be allowed in regexp literals
    regexdash   : true  // if unescaped first/last dash (-) inside brackets
                        // should be tolerated
  }
};

// These are the JSHint options that can take any value
// (we use this object to detect invalid options)
exports.val = {

  /**
   * This option lets you set the maximum length of a line.
   *
   * @deprecated JSHint is limiting its scope to issues of code correctness. If
   *             you would like to enforce rules relating to code style, check
   *             out [the JSCS project](https://github.com/jscs-dev/node-jscs).
   */
  maxlen       : false,

  /**
   * This option sets a specific tab width for your code.
   *
   * @deprecated JSHint is limiting its scope to issues of code correctness. If
   *             you would like to enforce rules relating to code style, check
   *             out [the JSCS project](https://github.com/jscs-dev/node-jscs).
   */
  indent       : false,

  /**
   * This options allows you to set the maximum amount of warnings JSHint will
   * produce before giving up. Default is 50.
   */
  maxerr       : false,

  /**
   * This option allows you to control which variables JSHint considers to be
   * implicitly defined in the environment. Configure it with an array of
   * string values. Prefixing a variable name with a hyphen (-) character will
   * remove that name from the collection of predefined variables.
   *
   * JSHint will consider variables declared in this way to be read-only.
   *
   * This option cannot be specified in-line; it may only be used via the
   * JavaScript API or from an external configuration file.
   */
  predef       : false,

  /**
   * This option can be used to specify a white list of global variables that
   * are not formally defined in the source code. This is most useful when
   * combined with the `undef` option in order to suppress warnings for
   * project-specific global variables.
   *
   * Setting an entry to `true` enables reading and writing to that variable.
   * Setting it to `false` will trigger JSHint to consider that variable
   * read-only.
   *
   * See also the "environment" options: a set of options to be used as short
   * hand for enabling global variables defined in common JavaScript
   * environments.
   *
   * To configure `globals` within an individual file, see [Inline
   * Configuration](http://jshint.com/docs/#inline-configuration).
   */
  globals      : false,

  /**
   * This option enforces the consistency of quotation marks used throughout
   * your code. It accepts three values: `true` if you don't want to enforce
   * one particular style but want some consistency, `"single"` if you want to
   * allow only single quotes and `"double"` if you want to allow only double
   * quotes.
   *
   * @deprecated JSHint is limiting its scope to issues of code correctness. If
   *             you would like to enforce rules relating to code style, check
   *             out [the JSCS project](https://github.com/jscs-dev/node-jscs).
   */
  quotmark     : false,

  scope        : false,

  /**
   * This option lets you set the max number of statements allowed per function:
   *
   *     // jshint maxstatements:4
   *
   *     function main() {
   *       var i = 0;
   *       var j = 0;
   *
   *       // Function declarations count as one statement. Their bodies
   *       // don't get taken into account for the outer function.
   *       function inner() {
   *         var i2 = 1;
   *         var j2 = 1;
   *
   *         return i2 + j2;
   *       }
   *
   *       j = i + j;
   *       return j; // JSHint: Too many statements per function. (5)
   *     }
   */
  maxstatements: false,

  /**
   * This option lets you control how nested do you want your blocks to be:
   *
   *     // jshint maxdepth:2
   *
   *     function main(meaning) {
   *       var day = true;
   *
   *       if (meaning === 42) {
   *         while (day) {
   *           shuffle();
   *
   *           if (tired) { // JSHint: Blocks are nested too deeply (3).
   *               sleep();
   *           }
   *         }
   *       }
   *     }
   */
  maxdepth     : false,

  /**
   * This option lets you set the max number of formal parameters allowed per
   * function:
   *
   *     // jshint maxparams:3
   *
   *     function login(request, onSuccess) {
   *       // ...
   *     }
   *
   *     // JSHint: Too many parameters per function (4).
   *     function logout(request, isManual, whereAmI, onSuccess) {
   *       // ...
   *     }
   */
  maxparams    : false,

  /**
   * This option lets you control cyclomatic complexity throughout your code.
   * Cyclomatic complexity measures the number of linearly independent paths
   * through a program's source code. Read more about [cyclomatic complexity on
   * Wikipedia](http://en.wikipedia.org/wiki/Cyclomatic_complexity).
   */
  maxcomplexity: false,

  /**
   * This option suppresses warnings about variable shadowing i.e. declaring a
   * variable that had been already declared somewhere in the outer scope.
   *
   * - "inner"  - check for variables defined in the same scope only
   * - "outer"  - check for variables defined in outer scopes as well
   * - false    - same as inner
   * - true     - allow variable shadowing
   */
  shadow       : false,

  /**
   * This option requires the code to run in ECMAScript 5's strict mode.
   * [Strict mode](https://developer.mozilla.org/en/JavaScript/Strict_mode)
   * is a way to opt in to a restricted variant of JavaScript. Strict mode
   * eliminates some JavaScript pitfalls that didn't cause errors by changing
   * them to produce errors.  It also fixes mistakes that made it difficult
   * for the JavaScript engines to perform certain optimizations.
   *
   * - "global"  - there must be a `"use strict";` directive at global level
   * - "implied" - lint the code as if there is the `"use strict";` directive
   * - false     - disable warnings about strict mode
   * - true      - there must be a `"use strict";` directive at function level;
   *               this is preferable for scripts intended to be loaded in web
   *               browsers directly because enabling strict mode globally
   *               could adversely effect other scripts running on the same
   *               page
   */
  strict      : true,

  /**
   * This option warns when you define and never use your variables. It is very
   * useful for general code cleanup, especially when used in addition to
   * `undef`.
   *
   *     // jshint unused:true
   *
   *     function test(a, b) {
   *       var c, d = 2;
   *
   *       return a + d;
   *     }
   *
   *     test(1, 2);
   *
   *     // Line 3: 'b' was defined but never used.
   *     // Line 4: 'c' was defined but never used.
   *
   * In addition to that, this option will warn you about unused global
   * variables declared via the `global` directive.
   *
   * When set to `true`, unused parameters that are followed by a used
   * parameter will not produce warnings. This option can be set to `vars` to
   * only check for variables, not function parameters, or `strict` to check
   * all variables and parameters.
   */
  unused       : true,

  /**
   * This option prohibits the use of a variable before it was defined.
   * JavaScript has function scope only and, in addition to that, all variables
   * are always moved—or hoisted— to the top of the function. This behavior can
   * lead to some very nasty bugs and that's why it is safer to always use
   * variable only after they have been explicitly defined.
   *
   * Setting this option to "nofunc" will allow function declarations to be
   * ignored.
   *
   * For more in-depth understanding of scoping and hoisting in JavaScript,
   * read [JavaScript Scoping and
   * Hoisting](http://www.adequatelygood.com/2010/2/JavaScript-Scoping-and-Hoisting)
   * by Ben Cherry.
   */
  latedef      : false,

  ignore       : false, // start/end ignoring lines of code, bypassing the lexer
                        //   start    - start ignoring lines, including the current line
                        //   end      - stop ignoring lines, starting on the next line
                        //   line     - ignore warnings / errors for just a single line
                        //              (this option does not bypass the lexer)

  ignoreDelimiters: false, // array of start/end delimiters used to ignore
                           // certain chunks from code

  /**
   * This option is used to specify the ECMAScript version to which the code
   * must adhere. It can assume one of the following values:
   *  - `3` - If you need your program to be executable
   *    in older browsers—such as Internet Explorer 6/7/8/9—and other legacy
   *    JavaScript environments
   *  - `5` - To enable syntax first defined in [the ECMAScript 5.1
   *    specification](http://www.ecma-international.org/ecma-262/5.1/index.html).
   *    This includes allowing reserved keywords as object properties.
   *  - `6` - To tell JSHint that your code uses [ECMAScript
   *    6](http://www.ecma-international.org/ecma-262/6.0/index.html) specific
   *    syntax. Note that not all browsers implement them.
   *  - `7` - To enable language features introduced by [ECMAScript
   *    7](https://www.ecma-international.org/ecma-262/7.0/index.html). Notable
   *    additions: the exponentiation operator.
   *  - `8` - To enable language features introduced by [ECMAScript
   *    8](https://www.ecma-international.org/ecma-262/8.0/index.html). Notable
   *    additions: async functions, shared memory, and atomics
   *  - `9` - To enable language features introduced by [ECMAScript
   *    9](https://www.ecma-international.org/ecma-262/9.0/index.html). Notable
   *    additions: asynchronous iteration, rest/spread properties, and various
   *    RegExp extensions
   */
  esversion: 5
};

/**
 * Unstable options allow control for parsing and linting of proposed additions
 * to the JavaScript language. Just like the language features they describe,
 * the presence and behavior of these options is volatile; JSHint reserves the
 * right to remove or modify them between major version releases.
 */
exports.unstable = {
};

// These are JSHint boolean options which are shared with JSLint
// where the definition in JSHint is opposite JSLint
exports.inverted = {
  bitwise : true,
  forin   : true,
  newcap  : true,
  plusplus: true,
  regexp  : true,
  undef   : true,

  // Inverted and renamed, use JSHint name here
  eqeqeq  : true,
  strict  : true
};

exports.validNames = Object.keys(exports.val)
  .concat(Object.keys(exports.bool.relaxing))
  .concat(Object.keys(exports.bool.enforcing))
  .concat(Object.keys(exports.bool.obsolete))
  .concat(Object.keys(exports.bool.environments))
  .concat(["unstable"]);

exports.unstableNames = Object.keys(exports.unstable);

// These are JSHint boolean options which are shared with JSLint
// where the name has been changed but the effect is unchanged
exports.renamed = {
  eqeq   : "eqeqeq",
  windows: "wsh",
  sloppy : "strict"
};

exports.removed = {
  nomen: true,
  onevar: true,
  passfail: true,
  white: true,
  gcl: true,
  smarttabs: true,
  trailing: true
};

// Add options here which should not be automatically enforced by
// `enforceall`.
exports.noenforceall = {
  varstmt: true,
  strict: true,
  regexpu: true
};