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Build # 2952

Build Type

push

travis-ci

Committed by

rwaldron

Commit Message

Coverage: add "istanbul ignore next" to lines that are not currently covered by tests

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4476 of 4477 relevant lines covered (99.98%)

22871.69 hits per line

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99.97

/src/jshint.js

/*!
 * JSHint, by JSHint Community.
 *
 * This file (and this file only) is licensed under the same slightly modified
 * MIT license that JSLint is. It stops evil-doers everywhere:
 *
 *   Copyright (c) 2002 Douglas Crockford  (www.JSLint.com)
 *
 *   Permission is hereby granted, free of charge, to any person obtaining
 *   a copy of this software and associated documentation files (the "Software"),
 *   to deal in the Software without restriction, including without limitation
 *   the rights to use, copy, modify, merge, publish, distribute, sublicense,
 *   and/or sell copies of the Software, and to permit persons to whom
 *   the Software is furnished to do so, subject to the following conditions:
 *
 *   The above copyright notice and this permission notice shall be included
 *   in all copies or substantial portions of the Software.
 *
 *   The Software shall be used for Good, not Evil.
 *
 *   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 *   IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 *   FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 *   AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 *   LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 *   FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 *   DEALINGS IN THE SOFTWARE.
 *
 */

/*jshint quotmark:double */
/*exported console */

var _            = require("lodash");
var events       = require("events");
var vars         = require("./vars.js");
var messages     = require("./messages.js");
var Lexer        = require("./lex.js").Lexer;
var reg          = require("./reg.js");
var state        = require("./state.js").state;
var style        = require("./style.js");
var options      = require("./options.js");
var scopeManager = require("./scope-manager.js");
var prodParams   = require("./prod-params.js");

// We need this module here because environments such as IE and Rhino
// don't necessarilly expose the 'console' API and browserify uses
// it to log things. It's a sad state of affair, really.
var console = require("console-browserify");

// We build the application inside a function so that we produce only a singleton
// variable. That function will be invoked immediately, and its return value is
// the JSHINT function itself.

var JSHINT = (function() {
  "use strict";

  var api, // Extension API

    // These are operators that should not be used with the ! operator.
    bang = {
      "<"  : true,
      "<=" : true,
      "==" : true,
      "===": true,
      "!==": true,
      "!=" : true,
      ">"  : true,
      ">=" : true,
      "+"  : true,
      "-"  : true,
      "*"  : true,
      "/"  : true,
      "%"  : true
    },

    declared, // Globals that were declared using /*global ... */ syntax.

    functions, // All of the functions

    inblock,
    indent,
    lookahead,
    lex,
    member,
    membersOnly,
    predefined,    // Global variables defined by option

    urls,

    extraModules = [],
    emitter = new events.EventEmitter();

  function checkOption(name, isStable, t) {
    var type, validNames;

    if (isStable) {
      type = "";
      validNames = options.validNames;
    } else {
      type = "unstable ";
      validNames = options.unstableNames;
    }

    name = name.trim();

    if (/^[+-]W\d{3}$/g.test(name)) {
      return true;
    }

    if (validNames.indexOf(name) === -1) {
      if (t.type !== "jslint" && !_.has(options.removed, name)) {
        error("E001", t, type, name);
        return false;
      }
    }

    return true;
  }

  function isString(obj) {
    return Object.prototype.toString.call(obj) === "[object String]";
  }

  function isIdentifier(tkn, value) {
    if (!tkn)
      return false;

    if (!tkn.identifier || tkn.value !== value)
      return false;

    return true;
  }

  /**
   * ES3 defined a set of "FutureReservedWords" in order "to allow for the
   * possibility of future adoption of [proposed] extensions."
   *
   * ES5 reduced the set of FutureReservedWords, in some cases by using them to
   * define new syntactic forms (e.g. `class` and `const`) and in other cases
   * by simply allowing their use as Identifiers (e.g. `int` and `goto`).
   * Separately, ES5 introduced new restrictions on certain tokens, but limited
   * the restriction to strict mode code (e.g. `let` and `yield`).
   *
   * This function determines if a given token describes a reserved word
   * according to the current state of the parser.
   *
   * @param {number} context - the parsing context; see `prod-params.js` for
   *                           more information
   * @param {Token} token
   */
  function isReserved(context, token) {
    if (!token.reserved) {
      return false;
    }
    var meta = token.meta;

    if (meta && meta.isFutureReservedWord) {
      if (state.inES5()) {
        // ES3 FutureReservedWord in an ES5 environment.
        if (!meta.es5) {
          return false;
        }

        if (token.isProperty) {
          return false;
        }
      }
    } else if (meta && meta.es5 && !state.inES5()) {
      return false;
    }

    // Some identifiers are reserved only within a strict mode environment.
    if (meta && meta.strictOnly && state.inES5()) {
      if (!state.option.strict && !state.isStrict()) {
        return false;
      }
    }

    if (token.id === "await" && (!(context & prodParams.async) && !state.option.module)) {
      return false;
    }

    return true;
  }

  function supplant(str, data) {
    return str.replace(/\{([^{}]*)\}/g, function(a, b) {
      var r = data[b];
      return typeof r === "string" || typeof r === "number" ? r : a;
    });
  }

  function combine(dest, src) {
    Object.keys(src).forEach(function(name) {
      if (_.has(JSHINT.blacklist, name)) return;
      dest[name] = src[name];
    });
  }

  function processenforceall() {
    if (state.option.enforceall) {
      for (var enforceopt in options.bool.enforcing) {
        if (state.option[enforceopt] === undefined &&
            !options.noenforceall[enforceopt]) {
          state.option[enforceopt] = true;
        }
      }
      for (var relaxopt in options.bool.relaxing) {
        if (state.option[relaxopt] === undefined) {
          state.option[relaxopt] = false;
        }
      }
    }
  }

  /**
   * Apply all linting options according to the status of the `state` object.
   */
  function applyOptions() {
    var badESOpt = null;
    processenforceall();

    /**
     * TODO: Remove in JSHint 3
     */
    badESOpt = state.inferEsVersion();
    if (badESOpt) {
      quit("E059", state.tokens.next, "esversion", badESOpt);
    }

    if (state.inES5()) {
      combine(predefined, vars.ecmaIdentifiers[5]);
    }

    if (state.inES6()) {
      combine(predefined, vars.ecmaIdentifiers[6]);
    }

    if (state.inES8()) {
      combine(predefined, vars.ecmaIdentifiers[8]);
    }

    /**
     * Use `in` to check for the presence of any explicitly-specified value for
     * `globalstrict` because both `true` and `false` should trigger an error.
     */
    if (state.option.strict === "global" && "globalstrict" in state.option) {
      quit("E059", state.tokens.next, "strict", "globalstrict");
    }

    if (state.option.module) {
      /**
       * TODO: Extend this restriction to *all* ES6-specific options.
       */
      if (!state.inES6()) {
        warning("W134", state.tokens.next, "module", 6);
      }
    }

    if (state.option.regexpu) {
      /**
       * TODO: Extend this restriction to *all* ES6-specific options.
       */
      if (!state.inES6()) {
        warning("W134", state.tokens.next, "regexpu", 6);
      }
    }

    if (state.option.couch) {
      combine(predefined, vars.couch);
    }

    if (state.option.qunit) {
      combine(predefined, vars.qunit);
    }

    if (state.option.rhino) {
      combine(predefined, vars.rhino);
    }

    if (state.option.shelljs) {
      combine(predefined, vars.shelljs);
      combine(predefined, vars.node);
    }
    if (state.option.typed) {
      combine(predefined, vars.typed);
    }

    if (state.option.phantom) {
      combine(predefined, vars.phantom);
    }

    if (state.option.prototypejs) {
      combine(predefined, vars.prototypejs);
    }

    if (state.option.node) {
      combine(predefined, vars.node);
      combine(predefined, vars.typed);
    }

    if (state.option.devel) {
      combine(predefined, vars.devel);
    }

    if (state.option.dojo) {
      combine(predefined, vars.dojo);
    }

    if (state.option.browser) {
      combine(predefined, vars.browser);
      combine(predefined, vars.typed);
    }

    if (state.option.browserify) {
      combine(predefined, vars.browser);
      combine(predefined, vars.typed);
      combine(predefined, vars.browserify);
    }

    if (state.option.nonstandard) {
      combine(predefined, vars.nonstandard);
    }

    if (state.option.jasmine) {
      combine(predefined, vars.jasmine);
    }

    if (state.option.jquery) {
      combine(predefined, vars.jquery);
    }

    if (state.option.mootools) {
      combine(predefined, vars.mootools);
    }

    if (state.option.worker) {
      combine(predefined, vars.worker);
    }

    if (state.option.wsh) {
      combine(predefined, vars.wsh);
    }

    if (state.option.yui) {
      combine(predefined, vars.yui);
    }

    if (state.option.mocha) {
      combine(predefined, vars.mocha);
    }
  }

  // Produce an error warning.
  function quit(code, token, a, b) {
    var percentage = Math.floor((token.line / state.lines.length) * 100);
    var message = messages.errors[code].desc;

    var exception = {
      name: "JSHintError",
      line: token.line,
      character: token.from,
      message: message + " (" + percentage + "% scanned).",
      raw: message,
      code: code,
      a: a,
      b: b
    };

    exception.reason = supplant(message, exception) + " (" + percentage +
      "% scanned).";

    throw exception;
  }

  function removeIgnoredMessages() {
    var ignored = state.ignoredLines;

    if (_.isEmpty(ignored)) return;
    JSHINT.errors = _.reject(JSHINT.errors, function(err) { return ignored[err.line] });
  }

  function warning(code, t, a, b, c, d) {
    var ch, l, w, msg;

    if (/^W\d{3}$/.test(code)) {
      if (state.ignored[code])
        return;

      msg = messages.warnings[code];
    } else if (/E\d{3}/.test(code)) {
      msg = messages.errors[code];
    } else if (/I\d{3}/.test(code)) {
      msg = messages.info[code];
    }

    t = t || state.tokens.next || {};
    if (t.id === "(end)") {  // `~
      t = state.tokens.curr;
    }

    l = t.line;
    ch = t.from;

    w = {
      id: "(error)",
      raw: msg.desc,
      code: msg.code,
      evidence: state.lines[l - 1] || "",
      line: l,
      character: ch,
      scope: JSHINT.scope,
      a: a,
      b: b,
      c: c,
      d: d
    };

    w.reason = supplant(msg.desc, w);
    JSHINT.errors.push(w);

    removeIgnoredMessages();

    if (JSHINT.errors.length >= state.option.maxerr)
      quit("E043", t);

    return w;
  }

  function warningAt(m, l, ch, a, b, c, d) {
    return warning(m, {
      line: l,
      from: ch
    }, a, b, c, d);
  }

  function error(m, t, a, b, c, d) {
    warning(m, t, a, b, c, d);
  }

  function errorAt(m, l, ch, a, b, c, d) {
    return error(m, {
      line: l,
      from: ch
    }, a, b, c, d);
  }

  // Tracking of "internal" scripts, like eval containing a static string
  function addEvalCode(elem, token) {
    JSHINT.internals.push({
      id: "(internal)",
      elem: elem,
      token: token,
      code: token.value.replace(/([^\\])(\\*)\2\\n/g, "$1\n")
    });
  }

  /**
   * Process an inline linting directive
   *
   * @param {Token} directiveToken - the directive-bearing comment token
   * @param {Token} previous - the token that preceeds the directive
   */
  function lintingDirective(directiveToken, previous) {
    var body = directiveToken.body.split(",")
      .map(function(s) { return s.trim(); });
    var predef = {};

    if (directiveToken.type === "falls through") {
      previous.caseFallsThrough = true;
      return;
    }

    if (directiveToken.type === "globals") {
      body.forEach(function(g, idx) {
        g = g.split(":");
        var key = g[0].trim();
        var val = (g[1] || "").trim();

        if (key === "-" || !key.length) {
          // Ignore trailing comma
          if (idx > 0 && idx === body.length - 1) {
            return;
          }
          error("E002", directiveToken);
          return;
        }

        if (key.charAt(0) === "-") {
          key = key.slice(1);
          val = false;

          JSHINT.blacklist[key] = key;
          delete predefined[key];
        } else {
          predef[key] = (val === "true");
        }
      });

      combine(predefined, predef);

      for (var key in predef) {
        if (_.has(predef, key)) {
          declared[key] = directiveToken;
        }
      }
    }

    if (directiveToken.type === "exported") {
      body.forEach(function(e, idx) {
        if (!e.length) {
          // Ignore trailing comma
          if (idx > 0 && idx === body.length - 1) {
            return;
          }
          error("E002", directiveToken);
          return;
        }

        state.funct["(scope)"].addExported(e);
      });
    }

    if (directiveToken.type === "members") {
      membersOnly = membersOnly || {};

      body.forEach(function(m) {
        var ch1 = m.charAt(0);
        var ch2 = m.charAt(m.length - 1);

        if (ch1 === ch2 && (ch1 === "\"" || ch1 === "'")) {
          m = m
            .substr(1, m.length - 2)
            .replace("\\\"", "\"");
        }

        membersOnly[m] = false;
      });
    }

    var numvals = [
      "maxstatements",
      "maxparams",
      "maxdepth",
      "maxcomplexity",
      "maxerr",
      "maxlen",
      "indent"
    ];

    if (directiveToken.type === "jshint" || directiveToken.type === "jslint" ||
      directiveToken.type === "jshint.unstable") {
      body.forEach(function(g) {
        g = g.split(":");
        var key = g[0].trim();
        var val = (g[1] || "").trim();

        if (!checkOption(key, directiveToken.type !== "jshint.unstable", directiveToken)) {
          return;
        }

        if (numvals.indexOf(key) >= 0) {
          // GH988 - numeric options can be disabled by setting them to `false`
          if (val !== "false") {
            val = +val;

            if (typeof val !== "number" || !isFinite(val) || val <= 0 || Math.floor(val) !== val) {
              error("E032", directiveToken, g[1].trim());
              return;
            }

            state.option[key] = val;
          } else {
            state.option[key] = key === "indent" ? 4 : false;
          }

          return;
        }

        if (key === "validthis") {
          // `validthis` is valid only within a function scope.

          if (state.funct["(global)"])
            return void error("E009");

          if (val !== "true" && val !== "false")
            return void error("E002", directiveToken);

          state.option.validthis = (val === "true");
          return;
        }

        if (key === "quotmark") {
          switch (val) {
          case "true":
          case "false":
            state.option.quotmark = (val === "true");
            break;
          case "double":
          case "single":
            state.option.quotmark = val;
            break;
          default:
            error("E002", directiveToken);
          }
          return;
        }

        if (key === "shadow") {
          switch (val) {
          case "true":
            state.option.shadow = true;
            break;
          case "outer":
            state.option.shadow = "outer";
            break;
          case "false":
          case "inner":
            state.option.shadow = "inner";
            break;
          default:
            error("E002", directiveToken);
          }
          return;
        }

        if (key === "unused") {
          switch (val) {
          case "true":
            state.option.unused = true;
            break;
          case "false":
            state.option.unused = false;
            break;
          case "vars":
          case "strict":
            state.option.unused = val;
            break;
          default:
            error("E002", directiveToken);
          }
          return;
        }

        if (key === "latedef") {
          switch (val) {
          case "true":
            state.option.latedef = true;
            break;
          case "false":
            state.option.latedef = false;
            break;
          case "nofunc":
            state.option.latedef = "nofunc";
            break;
          default:
            error("E002", directiveToken);
          }
          return;
        }

        if (key === "ignore") {
          switch (val) {
          case "line":
            state.ignoredLines[directiveToken.line] = true;
            removeIgnoredMessages();
            break;
          default:
            error("E002", directiveToken);
          }
          return;
        }

        if (key === "strict") {
          switch (val) {
          case "true":
            state.option.strict = true;
            break;
          case "false":
            state.option.strict = false;
            break;
          case "global":
          case "implied":
            state.option.strict = val;
            break;
          default:
            error("E002", directiveToken);
          }
          return;
        }

        if (key === "module") {
          /**
           * TODO: Extend this restriction to *all* "environmental" options.
           */
          if (!hasParsedCode(state.funct)) {
            error("E055", directiveToken, "module");
          }
        }

        if (key === "esversion") {
          switch (val) {
          case "3":
          case "5":
          case "6":
          case "7":
          case "8":
          case "9":
            state.option.moz = false;
            state.option.esversion = +val;
            break;
          case "2015":
          case "2016":
          case "2017":
          case "2018":
            state.option.moz = false;
            // Translate specification publication year to version number.
            state.option.esversion = +val - 2009;
            break;
          default:
            error("E002", directiveToken);
          }
          if (!hasParsedCode(state.funct)) {
            error("E055", directiveToken, "esversion");
          }
          return;
        }

        var match = /^([+-])(W\d{3})$/g.exec(key);
        if (match) {
          // ignore for -W..., unignore for +W...
          state.ignored[match[2]] = (match[1] === "-");
          return;
        }

        var tn;
        if (val === "true" || val === "false") {
          if (directiveToken.type === "jslint") {
            tn = options.renamed[key] || key;
            state.option[tn] = (val === "true");

            if (options.inverted[tn] !== undefined) {
              state.option[tn] = !state.option[tn];
            }
          } else if (directiveToken.type === "jshint.unstable") {
            /* istanbul ignore next */
            state.option.unstable[key] = (val === "true");
          } else {
            state.option[key] = (val === "true");
          }

          return;
        }

        error("E002", directiveToken);
      });

      applyOptions();
    }
  }

  /**
   * Return a token beyond the token available in `state.tokens.next`. If no
   * such token exists, return the "(end)" token. This function is used to
   * determine parsing strategies in cases where the value of the next token
   * does not provide sufficient information, as is the case with `for` loops,
   * e.g.:
   *
   *     for ( var i in ...
   *
   * versus:
   *
   *     for ( var i = ...
   *
   * @param {number} [p] - offset of desired token; defaults to 0
   *
   * @returns {token}
   */
  function peek(p) {
    var i = p || 0, j = lookahead.length, t;

    if (i < j) {
      return lookahead[i];
    }

    while (j <= i) {
      t = lex.token();

      // When the lexer is exhausted, this function should produce the "(end)"
      // token, even in cases where the requested token is beyond the end of
      // the input stream.
      if (!t) {
        // If the lookahead buffer is empty, the expected "(end)" token was
        // already emitted by the most recent invocation of `advance` and is
        // available as the next token.
        if (!lookahead.length) {
          return state.tokens.next;
        }

        return lookahead[j - 1];
      }

      lookahead[j] = t;
      j += 1;
    }

    return t;
  }

  function peekIgnoreEOL() {
    var i = 0;
    var t;
    do {
      t = peek(i++);
    } while (t.id === "(endline)");
    return t;
  }

  /**
   * Consume the next token.
   *
   * @param {string} [expected] - the expected value of the next token's `id`
   *                              property (in the case of punctuators) or
   *                              `value` property (in the case of identifiers
   *                              and literals); if unspecified, any token will
   *                              be accepted
   * @param {object} [relatedToken] - the token that informed the expected
   *                                  value, if any (for example: the opening
   *                                  brace when a closing brace is expected);
   *                                  used to produce more meaningful errors
   */
  function advance(expected, relatedToken) {
    var nextToken = state.tokens.next;

    if (expected && nextToken.id !== expected) {
      if (relatedToken) {
        if (nextToken.id === "(end)") {
          error("E019", relatedToken, relatedToken.id);
        } else {
          error("E020", nextToken, expected, relatedToken.id,
            relatedToken.line, nextToken.value);
        }
      } else if (nextToken.type !== "(identifier)" || nextToken.value !== expected) {
        error("E021", nextToken, expected, nextToken.value);
      }
    }

    state.tokens.prev = state.tokens.curr;
    state.tokens.curr = state.tokens.next;
    for (;;) {
      state.tokens.next = lookahead.shift() || lex.token();

      if (!state.tokens.next) { // No more tokens left, give up
        quit("E041", state.tokens.curr);
      }

      if (state.tokens.next.id === "(end)" || state.tokens.next.id === "(error)") {
        return;
      }

      if (state.tokens.next.check) {
        state.tokens.next.check();
      }

      if (state.tokens.next.isSpecial) {
        lintingDirective(state.tokens.next, state.tokens.curr);
      } else {
        if (state.tokens.next.id !== "(endline)") {
          break;
        }
      }
    }
  }

  /**
   * Determine whether a given token is an operator.
   *
   * @param {token} token
   *
   * @returns {boolean}
   */
  function isOperator(token) {
    return token.first || token.right || token.left || token.id === "yield" || token.id === "await";
  }

  function isEndOfExpr(context, curr, next) {
    if (arguments.length <= 1) {
      curr = state.tokens.curr;
      next = state.tokens.next;
    }

    if (next.id === "in" && context & prodParams.noin) {
      return true;
    }
    if (next.id === ";" || next.id === "}" || next.id === ":") {
      return true;
    }
    if (next.infix === curr.infix || curr.ltBoundary === "after" ||
      next.ltBoundary === "before") {
      return curr.line !== startLine(next);
    }
    return false;
  }

  /**
   * The `expression` function is the heart of JSHint's parsing behaior. It is
   * based on the Pratt parser, but it extends that model with a `fud` method.
   * Short for "first null denotation," it it similar to the `nud` ("null
   * denotation") function, but it is only used on the first token of a
   * statement. This simplifies usage in statement-oriented languages like
   * JavaScript.
   *
   * .nud  Null denotation
   * .fud  First null denotation
   * .led  Left denotation
   *  lbp  Left binding power
   *  rbp  Right binding power
   *
   * They are elements of the parsing method called Top Down Operator Precedence.
   *
   * In addition to parsing, this function applies a number of linting patterns.
   *
   * @param {number} context - the parsing context (a bitfield describing
   *                           conditions of the current parsing operation
   *                           which can influence how the next tokens are
   *                           interpreted); see `prod-params.js` for more
   *                           detail)
   * @param {number} rbp - the right-binding power of the token to be consumed
   */
  function expression(context, rbp) {
    var left, isArray = false, isObject = false;
    var initial = context & prodParams.initial;
    var curr;

    context &= ~prodParams.initial;

    state.nameStack.push();

    if (state.tokens.next.id === "(end)")
      error("E006", state.tokens.curr);

    advance();

    if (initial) {
      state.funct["(verb)"] = state.tokens.curr.value;
      state.tokens.curr.beginsStmt = true;
    }

    curr = state.tokens.curr;

    if (initial && curr.fud && (!curr.useFud || curr.useFud(context))) {
      left = state.tokens.curr.fud(context);
    } else {
      if (state.tokens.curr.nud) {
        left = state.tokens.curr.nud(context, rbp);
      } else {
        error("E030", state.tokens.curr, state.tokens.curr.id);
      }

      while (rbp < state.tokens.next.lbp && !isEndOfExpr(context)) {
        isArray = state.tokens.curr.value === "Array";
        isObject = state.tokens.curr.value === "Object";

        // #527, new Foo.Array(), Foo.Array(), new Foo.Object(), Foo.Object()
        // Line breaks in IfStatement heads exist to satisfy the checkJSHint
        // "Line too long." error.
        if (left && (left.value || (left.first && left.first.value))) {
          // If the left.value is not "new", or the left.first.value is a "."
          // then safely assume that this is not "new Array()" and possibly
          // not "new Object()"...
          if (left.value !== "new" ||
            (left.first && left.first.value && left.first.value === ".")) {
            isArray = false;
            // ...In the case of Object, if the left.value and state.tokens.curr.value
            // are not equal, then safely assume that this not "new Object()"
            if (left.value !== state.tokens.curr.value) {
              isObject = false;
            }
          }
        }

        advance();

        if (isArray && state.tokens.curr.id === "(" && state.tokens.next.id === ")") {
          warning("W009", state.tokens.curr);
        }

        if (isObject && state.tokens.curr.id === "(" && state.tokens.next.id === ")") {
          warning("W010", state.tokens.curr);
        }

        if (left && state.tokens.curr.led) {
          left = state.tokens.curr.led(context, left);
        } else {
          error("E033", state.tokens.curr, state.tokens.curr.id);
        }
      }
    }

    state.nameStack.pop();

    return left;
  }


  // Functions for conformance of style.

  function startLine(token) {
    return token.startLine || token.line;
  }

  function nobreaknonadjacent(left, right) {
    if (!state.option.laxbreak && left.line !== startLine(right)) {
      warning("W014", right, right.value);
    }
  }

  function nolinebreak(t) {
    t = t;
    if (t.line !== startLine(state.tokens.next)) {
      warning("E022", t, t.value);
    }
  }

  function nobreakcomma(left, right) {
    if (left.line !== startLine(right)) {
      if (!state.option.laxcomma) {
        if (parseComma.first) {
          warning("I001");
          parseComma.first = false;
        }
        warning("W014", left, right.value);
      }
    }
  }

  function parseComma(opts) {
    opts = opts || {};

    if (!opts.peek) {
      nobreakcomma(state.tokens.curr, state.tokens.next);
      advance(",");
    } else {
      nobreakcomma(state.tokens.prev, state.tokens.curr);
    }

    if (state.tokens.next.identifier && !(opts.property && state.inES5())) {
      // Keywords that cannot follow a comma operator.
      switch (state.tokens.next.value) {
      case "break":
      case "case":
      case "catch":
      case "continue":
      case "default":
      case "do":
      case "else":
      case "finally":
      case "for":
      case "if":
      case "in":
      case "instanceof":
      case "return":
      case "switch":
      case "throw":
      case "try":
      case "var":
      case "let":
      case "while":
      case "with":
        error("E024", state.tokens.next, state.tokens.next.value);
        return false;
      }
    }

    if (state.tokens.next.type === "(punctuator)") {
      switch (state.tokens.next.value) {
      case "}":
      case "]":
      case ",":
      case ")":
        if (opts.allowTrailing) {
          return true;
        }

        error("E024", state.tokens.next, state.tokens.next.value);
        return false;
      }
    }
    return true;
  }

  /**
   * Factory function for creating "symbols"--objects that will be inherited by
   * tokens. The objects created by this function are stored in a symbol table
   * and set as the prototype of the tokens generated by the lexer.
   *
   * Note that this definition of "symbol" describes an implementation detail
   * of JSHint and is not related to the ECMAScript value type introduced in
   * ES2015.
   *
   * @param {string} s - the name of the token; for keywords (e.g. `void`) and
   *                     delimiters (e.g.. `[`), this is the token's text
   *                     representation; for literals (e.g. numbers) and other
   *                     "special" tokens (e.g. the end-of-file marker) this is
   *                     a parenthetical value
   * @param {number} p - the left-binding power of the token as used by the
   *                     Pratt parsing semantics
   *
   * @returns {object} - the object describing the JSHint symbol (provided to
   *                     support cases where further refinement is necessary)
   */
  function symbol(s, p) {
    var x = state.syntax[s];
    if (!x || typeof x !== "object") {
      state.syntax[s] = x = {
        id: s,
        lbp: p,
        // Symbols that accept a right-hand side do so with a binding power
        // that is commonly identical to their left-binding power. (This value
        // is relevant when determining if the grouping operator is necessary
        // to override the precedence of surrounding operators.) Because the
        // exponentiation operator's left-binding power and right-binding power
        // are distinct, the values must be encoded separately.
        rbp: p,
        value: s
      };
    }
    return x;
  }

  /**
   * Convenience function for defining delimiter symbols.
   *
   * @param {string} s - the name of the symbol
   *
   * @returns {object} - the object describing the JSHint symbol (provided to
   *                     support cases where further refinement is necessary)
   */
  function delim(s) {
    var x = symbol(s, 0);
    x.delim = true;
    return x;
  }

  /**
   * Convenience function for defining statement-denoting symbols.
   *
   * @param {string} s - the name of the symbol
   * @param {function} f - the first null denotation function for the symbol;
   *                       see the `expression` function for more detail
   *
   * @returns {object} - the object describing the JSHint symbol (provided to
   *                     support cases where further refinement is necessary)
   */
  function stmt(s, f) {
    var x = delim(s);
    x.identifier = x.reserved = true;
    x.fud = f;
    return x;
  }

  /**
   * Convenience function for defining block-statement-denoting symbols.
   *
   * A block-statement-denoting symbol is one like 'if' or 'for', which will be
   * followed by a block and will not have to end with a semicolon.
   *
   * @param {string} s - the name of the symbol
   * @param {function} - the first null denotation function for the symbol; see
   *                     the `expression` function for more detail
   *
   * @returns {object} - the object describing the JSHint symbol (provided to
   *                     support cases where further refinement is necessary)
   */
  function blockstmt(s, f) {
    var x = stmt(s, f);
    x.block = true;
    return x;
  }
  /**
   * Denote a given JSHint symbol as an identifier and a reserved keyword.
   *
   * @param {object} - a JSHint symbol value
   *
   * @returns {object} - the provided object
   */
  function reserveName(x) {
    var c = x.id.charAt(0);
    if ((c >= "a" && c <= "z") || (c >= "A" && c <= "Z")) {
      x.identifier = x.reserved = true;
    }
    return x;
  }

  /**
   * Convenience function for defining "prefix" symbols--operators that accept
   * expressions as a right-hand side.
   *
   * @param {string} s - the name of the symbol
   * @param {function} [f] - the first null denotation function for the symbol;
   *                         see the `expression` function for more detail
   *
   * @returns {object} - the object describing the JSHint symbol (provided to
   *                     support cases where further refinement is necessary)
   */
  function prefix(s, f) {
    var x = symbol(s, 150);
    reserveName(x);

    x.nud = (typeof f === "function") ? f : function(context) {
      this.arity = "unary";
      this.right = expression(context, 150);

      if (this.id === "++" || this.id === "--") {
        if (state.option.plusplus) {
          warning("W016", this, this.id);
        }

        if (this.right) {
          checkLeftSideAssign(context, this.right, this);
        }
      }

      return this;
    };

    return x;
  }

  /**
   * Convenience function for defining "type" symbols--those that describe
   * literal values.
   *
   * @param {string} s - the name of the symbol
   * @param {function} f - the first null denotation function for the symbol;
   *                       see the `expression` function for more detail
   *
   * @returns {object} - the object describing the JSHint symbol (provided to
   *                     support cases where further refinement is necessary)
   */
  function type(s, f) {
    var x = delim(s);
    x.type = s;
    x.nud = f;
    return x;
  }

  /**
   * Convenience function for defining JSHint symbols for reserved
   * keywords--those that are restricted from use as bindings (and as property
   * names in ECMAScript 3 environments).
   *
   * @param {string} s - the name of the symbol
   * @param {function} func - the first null denotation function for the
   *                          symbol; see the `expression` function for more
   *                          detail
   *
   * @returns {object} - the object describing the JSHint symbol (provided to
   *                     support cases where further refinement is necessary)
   */
  function reserve(name, func) {
    var x = type(name, func);
    x.identifier = true;
    x.reserved = true;
    return x;
  }

  /**
   * Convenience function for defining JSHint symbols for keywords that are
   * only reserved in some circumstances.
   *
   * @param {string} name - the name of the symbol
   * @param {object} [meta] - a collection of optional arguments
   * @param {function} [meta.nud] -the null denotation function for the symbol;
   *                   see the `expression` function for more detail
   * @param {boolean} [meta.es5] - `true` if the identifier is reserved
   *                               in ECMAScript 5 or later
   * @param {boolean} [meta.strictOnly] - `true` if the identifier is only
   *                                      reserved in strict mode code.
   *
   * @returns {object} - the object describing the JSHint symbol (provided to
   *                     support cases where further refinement is necessary)
   */
  function FutureReservedWord(name, meta) {
    var x = type(name, state.syntax["(identifier)"].nud);

    meta = meta || {};
    meta.isFutureReservedWord = true;

    x.value = name;
    x.identifier = true;
    x.reserved = true;
    x.meta = meta;

    return x;
  }

  /**
   * Convenience function for defining "infix" symbols--operators that require
   * operands as both "land-hand side" and "right-hand side".
   *
   * @param {string} s - the name of the symbol
   * @param {function} [f] - a function to be invoked that consumes the
   *                         right-hand side of the operator
   * @param {number} p - the left-binding power of the token as used by the
   *                     Pratt parsing semantics
   * @param {boolean} [w] - if `true`
   *
   * @returns {object} - the object describing the JSHint symbol (provided to
   *                     support cases where further refinement is necessary)
   */
  function infix(s, f, p, w) {
    var x = symbol(s, p);
    reserveName(x);
    x.infix = true;
    x.led = function(context, left) {
      if (!w) {
        nobreaknonadjacent(state.tokens.prev, state.tokens.curr);
      }
      if ((s === "in" || s === "instanceof") && left.id === "!") {
        warning("W018", left, "!");
      }
      if (typeof f === "function") {
        return f(context, left, this);
      } else {
        this.left = left;
        this.right = expression(context, p);
        return this;
      }
    };
    return x;
  }

  /**
   * Convenience function for defining the `=>` token as used in arrow
   * functions.
   *
   * @param {string} s - the name of the symbol
   *
   * @returns {object} - the object describing the JSHint symbol (provided to
   *                     support cases where further refinement is necessary)
   */
  function application(s) {
    var x = symbol(s, 42);

    x.infix = true;
    x.led = function(context, left) {
      nobreaknonadjacent(state.tokens.prev, state.tokens.curr);

      this.left = left;
      this.right = doFunction(context, { type: "arrow", loneArg: left });
      return this;
    };
    return x;
  }

  /**
   * Convenience function for defining JSHint symbols for relation operators.
   *
   * @param {string} s - the name of the symbol
   * @param {function} [f] - a function to be invoked to enforce any additional
   *                         linting rules.
   *
   * @returns {object} - the object describing the JSHint symbol (provided to
   *                     support cases where further refinement is necessary)
   */
  function relation(s, f) {
    var x = symbol(s, 100);

    x.infix = true;
    x.led = function(context, left) {
      nobreaknonadjacent(state.tokens.prev, state.tokens.curr);
      this.left = left;
      var right = this.right = expression(context, 100);

      if (isIdentifier(left, "NaN") || isIdentifier(right, "NaN")) {
        warning("W019", this);
      } else if (f) {
        f.apply(this, [context, left, right]);
      }

      if (!left || !right) {
        quit("E041", state.tokens.curr);
      }

      if (left.id === "!") {
        warning("W018", left, "!");
      }

      if (right.id === "!") {
        warning("W018", right, "!");
      }

      return this;
    };
    return x;
  }

  /**
   * Determine if a given token marks the beginning of a UnaryExpression.
   *
   * @param {object} token
   *
   * @returns {boolean}
   */
  function beginsUnaryExpression(token) {
    return token.arity === "unary" && token.id !== "++" && token.id !== "--";
  }

  var typeofValues = {};
  typeofValues.legacy = [
    // E4X extended the `typeof` operator to return "xml" for the XML and
    // XMLList types it introduced.
    // Ref: 11.3.2 The typeof Operator
    // http://www.ecma-international.org/publications/files/ECMA-ST/Ecma-357.pdf
    "xml",
    // IE<9 reports "unknown" when the `typeof` operator is applied to an
    // object existing across a COM+ bridge. In lieu of official documentation
    // (which does not exist), see:
    // http://robertnyman.com/2005/12/21/what-is-typeof-unknown/
    "unknown"
  ];
  typeofValues.es3 = [
    "undefined", "boolean", "number", "string", "function", "object",
  ];
  typeofValues.es3 = typeofValues.es3.concat(typeofValues.legacy);
  typeofValues.es6 = typeofValues.es3.concat("symbol");

  /**
   * Validate comparisons between the result of a `typeof` expression and a
   * string literal.
   *
   * @param {token} [left] - one of the values being compared
   * @param {token} [right] - the other value being compared
   * @param {object} state - the global state object (see `state.js`)
   *
   * @returns {boolean} - `false` if the second token describes a `typeof`
   *                       expression and the first token is a string literal
   *                       whose value is never returned by that operator;
   *                       `true` otherwise
   */
  function isTypoTypeof(left, right, state) {
    var values;

    if (state.option.notypeof)
      return false;

    if (!left || !right)
      return false;

    values = state.inES6() ? typeofValues.es6 : typeofValues.es3;

    if (right.type === "(identifier)" && right.value === "typeof" && left.type === "(string)")
      return !_.includes(values, left.value);

    return false;
  }

  /**
   * Determine if a given token describes the built-in `eval` function.
   *
   * @param {token} left
   * @param {object} state - the global state object (see `state.js`)
   *
   * @returns {boolean}
   */
  function isGlobalEval(left, state) {
    var isGlobal = false;

    // permit methods to refer to an "eval" key in their own context
    if (left.type === "this" && state.funct["(context)"] === null) {
      isGlobal = true;
    }
    // permit use of "eval" members of objects
    else if (left.type === "(identifier)") {
      if (state.option.node && left.value === "global") {
        isGlobal = true;
      }

      else if (state.option.browser && (left.value === "window" || left.value === "document")) {
        isGlobal = true;
      }
    }

    return isGlobal;
  }

  /**
   * Determine if a given token describes a property of a built-in object.
   *
   * @param {token} left
   *
   * @returns {boolean}
   */
  function findNativePrototype(left) {
    var natives = [
      "Array", "ArrayBuffer", "Boolean", "Collator", "DataView", "Date",
      "DateTimeFormat", "Error", "EvalError", "Float32Array", "Float64Array",
      "Function", "Infinity", "Intl", "Int16Array", "Int32Array", "Int8Array",
      "Iterator", "Number", "NumberFormat", "Object", "RangeError",
      "ReferenceError", "RegExp", "StopIteration", "String", "SyntaxError",
      "TypeError", "Uint16Array", "Uint32Array", "Uint8Array", "Uint8ClampedArray",
      "URIError"
    ];

    function walkPrototype(obj) {
      if (typeof obj !== "object") return;
      return obj.right === "prototype" ? obj : walkPrototype(obj.left);
    }

    function walkNative(obj) {
      while (!obj.identifier && typeof obj.left === "object")
        obj = obj.left;

      if (obj.identifier && natives.indexOf(obj.value) >= 0 &&
          state.funct["(scope)"].isPredefined(obj.value)) {
        return obj.value;
      }
    }

    var prototype = walkPrototype(left);
    if (prototype) return walkNative(prototype);
  }

  /**
   * Determine if the given token is a valid assignment target; emit errors
   * and/or warnings as appropriate
   *
   * @param {number} context - the parsing context; see `prod-params.js` for
   *                           more information
   * @param {token} left - the left hand side of the assignment
   * @param {token=} assignToken - the token for the assignment, used for
   *                               reporting
   * @param {object=} options - optional object
   * @param {boolean} options.allowDestructuring - whether to allow
   *                                               destructuring binding
   *
   * @returns {boolean} Whether the left hand side is OK
   */
  function checkLeftSideAssign(context, left, assignToken, options) {

    var allowDestructuring = options && options.allowDestructuring;

    assignToken = assignToken || left;

    if (state.option.freeze) {
      var nativeObject = findNativePrototype(left);
      if (nativeObject)
        warning("W121", left, nativeObject);
    }
    if (checkPunctuator(left, "...")) {
      /* istanbul ignore next */
      left = left.right;
    }

    if (left.identifier && !left.isMetaProperty) {
      // The `reassign` method also calls `modify`, but we are specific in
      // order to catch function re-assignment and globals re-assignment
      state.funct["(scope)"].block.reassign(left.value, left);
    }

    if (left.id === ".") {
      if (!left.left || left.left.value === "arguments" && !state.isStrict()) {
        warning("W143", assignToken);
      }

      state.nameStack.set(state.tokens.prev);
      return true;
    } else if (left.id === "{" || left.id === "[") {
      if (!allowDestructuring || !left.destructAssign) {
        if (left.id === "{" || !left.left) {
          warning("E031", assignToken);
        } else if (left.left.value === "arguments" && !state.isStrict()) {
          warning("W143", assignToken);
        }
      }

      if (left.id === "[") {
        state.nameStack.set(left.right);
      }

      return true;
    } else if (left.identifier && !isReserved(context, left) && !left.isMetaProperty &&
      left.value !== "eval" && left.value !== "arguments") {
      if (state.funct["(scope)"].labeltype(left.value) === "exception") {
        warning("W022", left);
      }
      state.nameStack.set(left);
      return true;
    }

    error("E031", assignToken);

    return false;
  }

  /**
   * Convenience function for defining JSHint symbols for assignment operators.
   *
   * @param {string} s - the name of the symbol
   * @param {function} [f] - a function to be invoked that consumes the
   *                         right-hand side of the operator (see the `infix`
   *                         function)
   * @param {number} p - the left-binding power of the token as used by the
   *                     Pratt parsing semantics
   *
   * @returns {object} - the object describing the JSHint symbol (provided to
   *                     support cases where further refinement is necessary)
   */
  function assignop(s, f, p) {
    var x = infix(s, typeof f === "function" ? f : function(context, left, that) {
      that.left = left;

      checkLeftSideAssign(context, left, that, { allowDestructuring: true });

      that.right = expression(context, 10);

      return that;
    }, p);

    x.exps = true;
    x.assign = true;
    return x;
  }

  /**
   * Convenience function for defining JSHint symbols for bitwise operators.
   *
   * @param {string} s - the name of the symbol
   * @param {function} [f] - the left denotation function for the symbol; see
   *                         the `expression` function for more detail
   * @param {number} p - the left-binding power of the token as used by the
   *                     Pratt parsing semantics
   *
   * @returns {object} - the object describing the JSHint symbol (provided to
   *                     support cases where further refinement is necessary)
   */
  function bitwise(s, f, p) {
    var x = symbol(s, p);
    reserveName(x);
    x.infix = true;
    x.led = (typeof f === "function") ? f : function(context, left) {
      if (state.option.bitwise) {
        warning("W016", this, this.id);
      }
      this.left = left;
      this.right = expression(context, p);
      return this;
    };
    return x;
  }

  /**
   * Convenience function for defining JSHint symbols for bitwise assignment
   * operators. See the `assignop` function for more detail.
   *
   * @param {string} s - the name of the symbol
   *
   * @returns {object} - the object describing the JSHint symbol (provided to
   *                     support cases where further refinement is necessary)
   */
  function bitwiseassignop(s) {
    return assignop(s, function(context, left, that) {
      if (state.option.bitwise) {
        warning("W016", that, that.id);
      }

      checkLeftSideAssign(context, left, that);

      that.right = expression(context, 10);

      return that;
    }, 20);
  }

  /**
   * Convenience function for defining JSHint symbols for those operators which
   * have a single operand that appears before them in the source code.
   *
   * @param {string} s - the name of the symbol
   *
   * @returns {object} - the object describing the JSHint symbol (provided to
   *                     support cases where further refinement is necessary)
   */
  function suffix(s) {
    var x = symbol(s, 150);

    x.led = function(context, left) {
      // this = suffix e.g. "++" punctuator
      // left = symbol operated e.g. "a" identifier or "a.b" punctuator
      if (state.option.plusplus) {
        warning("W016", this, this.id);
      }

      checkLeftSideAssign(context, left, this);

      this.left = left;
      return this;
    };
    return x;
  }

  /**
   * Retrieve the value of the current token if it is an identifier and
   * optionally advance the parser.
   *
   * @param {number} context - the parsing context; see `prod-params.js` for
   *                           more information
   * @param {boolean} [prop] -`true` if this identifier is that of an object
   *                           property
   * @param {boolean} [preserve] - `true` if the token should not be consumed
   *
   * @returns {string|undefined} - the value of the identifier, if present
   */
  function optionalidentifier(context, prop, preserve) {
    if (!state.tokens.next.identifier) {
      return;
    }

    if (!preserve) {
      advance();
    }

    var curr = state.tokens.curr;
    var val  = state.tokens.curr.value;

    if (!isReserved(context, curr)) {
      return val;
    }

    if (prop) {
      if (state.inES5()) {
        return val;
      }
    }

    if (val === "undefined") {
      /* istanbul ignore next */
      return val;
    }

    warning("W024", state.tokens.curr, state.tokens.curr.id);
    return val;
  }

  /**
   * Consume the "..." token which designates "spread" and "rest" operations if
   * it is present. If the operator is repeated, consume every repetition, and
   * issue a single error describing the syntax error.
   *
   * @param {string} operation - either "spread" or "rest"
   *
   * @returns {boolean} a value describing whether or not any tokens were
   *                    consumed in this way
   */
  function spreadrest(operation) {
    if (!checkPunctuator(state.tokens.next, "...")) {
      return false;
    }

    if (!state.inES6(true)) {
      warning("W119", state.tokens.next, operation + " operator", "6");
    }
    advance();

    if (checkPunctuator(state.tokens.next, "...")) {
      warning("E024", state.tokens.next, "...");
      while (checkPunctuator(state.tokens.next, "...")) {
        advance();
      }
    }

    return true;
  }

  /**
   * Ensure that the current token is an identifier and retrieve its value.
   *
   * @param {number} context - the parsing context; see `prod-params.js` for
   *                           more information
   * @param {boolean} [prop] -`true` if this identifier is that of an object
   *                           property
   *
   * @returns {string|undefined} - the value of the identifier, if present
   */
  function identifier(context, prop) {
    var i = optionalidentifier(context, prop, false);
    if (i) {
      return i;
    }

    error("E030", state.tokens.next, state.tokens.next.value);

    // The token should be consumed after a warning is issued so the parser
    // can continue as though an identifier were found. The semicolon token
    // should not be consumed in this way so that the parser interprets it as
    // a statement delimeter;
    if (state.tokens.next.id !== ";") {
      advance();
    }
  }


  /**
   * Determine if the provided token may be evaluated and emit a linting
   * warning if this is note the case.
   *
   * @param {token} controlToken
   */
  function reachable(controlToken) {
    var i = 0, t;
    if (state.tokens.next.id !== ";" || controlToken.inBracelessBlock) {
      return;
    }
    for (;;) {
      do {
        t = peek(i);
        i += 1;
      } while (t.id !== "(end)" && t.id === "(comment)");

      if (t.reach) {
        return;
      }
      if (t.id !== "(endline)") {
        if (t.id === "function") {
          if (state.option.latedef === true) {
            warning("W026", t);
          }
          break;
        }

        warning("W027", t, t.value, controlToken.value);
        break;
      }
    }
  }

  /**
   * Consume the semicolon that delimits the statement currently being parsed,
   * emitting relevant warnings/errors as appropriate.
   *
   * @param {token} stmt - token describing the statement under consideration
   */
  function parseFinalSemicolon(stmt) {
    if (state.tokens.next.id !== ";") {
      // don't complain about unclosed templates / strings
      if (state.tokens.next.isUnclosed) return advance();

      var sameLine = startLine(state.tokens.next) === state.tokens.curr.line &&
                     state.tokens.next.id !== "(end)";
      var blockEnd = checkPunctuator(state.tokens.next, "}");

      if (sameLine && !blockEnd && !(stmt.id === "do" && state.inES6(true))) {
        errorAt("E058", state.tokens.curr.line, state.tokens.curr.character);
      } else if (!state.option.asi) {

        // If this is the last statement in a block that ends on the same line
        // *and* option lastsemic is on, ignore the warning.  Otherwise, issue
        // a warning about missing semicolon.
        if (!(blockEnd && sameLine && state.option.lastsemic)) {
          warningAt("W033", state.tokens.curr.line, state.tokens.curr.character);
        }
      }
    } else {
      advance(";");
    }
  }

  /**
   * Consume a statement.
   *
   * @param {number} context - the parsing context; see `prod-params.js` for
   *                           more information
   *
   * @returns {token} - the token describing the statement
   */
  function statement(context) {
    var i = indent, r, t = state.tokens.next, hasOwnScope = false;

    context |= prodParams.initial;

    if (t.id === ";") {
      advance(";");
      return;
    }

    // Is this a labelled statement?
    var res = isReserved(context, t);

    // We're being more tolerant here: if someone uses
    // a FutureReservedWord (that is not meant to start a statement)
    // as a label, we warn but proceed anyway.

    if (res && t.meta && t.meta.isFutureReservedWord && !t.fud) {
      warning("W024", t, t.id);
      res = false;
    }

    if (t.identifier && !res && peek().id === ":") {
      advance();
      advance(":");

      hasOwnScope = true;
      state.funct["(scope)"].stack();
      state.funct["(scope)"].block.addBreakLabel(t.value, { token: state.tokens.curr });

      if (!state.tokens.next.labelled && state.tokens.next.value !== "{") {
        warning("W028", state.tokens.next, t.value, state.tokens.next.value);
      }

      t = state.tokens.next;
    }

    // Is it a lonely block?

    if (t.id === "{") {
      // Is it a switch case block?
      //
      //  switch (foo) {
      //    case bar: { <= here.
      //      ...
      //    }
      //  }
      var iscase = (state.funct["(verb)"] === "case" && state.tokens.curr.value === ":");
      block(context, true, true, false, false, iscase);

      if (hasOwnScope) {
        state.funct["(scope)"].unstack();
      }

      return;
    }

    // Parse the statement.

    r = expression(context, 0);

    if (r && !(r.identifier && r.value === "function") &&
        !(r.type === "(punctuator)" && r.left &&
          r.left.identifier && r.left.value === "function")) {
      if (!state.isStrict() && state.stmtMissingStrict()) {
        warning("E007");
      }
    }

    // Look for the final semicolon.

    if (!t.block) {
      if (!state.option.expr && (!r || !r.exps)) {
        warning("W030", state.tokens.curr);
      } else if (state.option.nonew && r && r.left && r.id === "(" && r.left.id === "new") {
        warning("W031", t);
      }
      parseFinalSemicolon(t);
    }


    // Restore the indentation.

    indent = i;
    if (hasOwnScope) {
      state.funct["(scope)"].unstack();
    }
    return r;
  }

  /**
   * Consume a series of statements until encountering either the end of the
   * program or a token that interrupts control flow.
   *
   * @param {number} context - the parsing context; see `prod-params.js` for
   *                           more information
   *
   * @returns {Array<token>} - the tokens consumed
   */
  function statements(context) {
    var a = [], p;

    while (!state.tokens.next.reach && state.tokens.next.id !== "(end)") {
      if (state.tokens.next.id === ";") {
        p = peek();

        if (!p || (p.id !== "(" && p.id !== "[")) {
          warning("W032");
        }

        advance(";");
      } else {
        a.push(statement(context));
      }
    }
    return a;
  }


  /**
   * Parse any directives in a directive prologue.
   */
  function directives() {
    var current = state.tokens.next;
    while (state.tokens.next.id === "(string)") {
      var next = peekIgnoreEOL();
      if (!isEndOfExpr(0, current, next)) {
        break;
      }
      current = next;

      advance();
      var directive = state.tokens.curr.value;
      if (state.directive[directive] ||
          (directive === "use strict" && state.option.strict === "implied")) {
        warning("W034", state.tokens.curr, directive);
      }

      // From ECMAScript 2016:
      //
      // > 14.1.2 Static Semantics: Early Errors
      // >
      // > [...]
      // > - It is a Syntax Error if ContainsUseStrict of FunctionBody is true
      // >   and IsSimpleParameterList of FormalParameters is false.
      if (directive === "use strict" && state.inES7() &&
        !state.funct["(global)"] && state.funct["(hasSimpleParams)"] === false) {
        error("E065", state.tokens.curr);
      }

      // there's no directive negation, so always set to true
      state.directive[directive] = true;

      parseFinalSemicolon(current);
    }

    if (state.isStrict()) {
      state.option.undef = true;
    }
  }

  /**
   * Parses a single block. A block is a sequence of statements wrapped in
   * braces.
   *
   * @param {number} context - parsing context
   * @param {boolean} ordinary - `true` for everything but function bodies and
   *                             try blocks
   * @param {boolean} [stmt] - `true` if block can be a single statement (e.g.
   *                           in if/for/while)
   * @param {boolean} [isfunc] - `true` if block is a function body
   * @param {boolean} [isfatarrow] - `true` if its a body of a fat arrow
   *                                 function
   * @param {boolean} [iscase] - `true` if block is a switch case block
   *
   * @returns {token} - the token describing the block
   */
  function block(context, ordinary, stmt, isfunc, isfatarrow, iscase) {
    var a,
      b = inblock,
      old_indent = indent,
      m,
      t,
      d;

    inblock = ordinary;

    t = state.tokens.next;

    var metrics = state.funct["(metrics)"];
    metrics.nestedBlockDepth += 1;
    metrics.verifyMaxNestedBlockDepthPerFunction();

    if (state.tokens.next.id === "{") {
      advance("{");

      // create a new block scope
      state.funct["(scope)"].stack();

      if (state.tokens.next.id !== "}") {
        indent += state.option.indent;
        while (!ordinary && state.tokens.next.from > indent) {
          indent += state.option.indent;
        }

        if (isfunc) {
          m = {};
          for (d in state.directive) {
            m[d] = state.directive[d];
          }
          directives();

          state.funct["(isStrict)"] = state.isStrict();

          if (state.option.strict && state.funct["(context)"]["(global)"]) {
            if (!m["use strict"] && !state.isStrict()) {
              warning("E007");
            }
          }
        }

        a = statements(context);

        metrics.statementCount += a.length;

        indent -= state.option.indent;
      } else if (isfunc) {
        // Ensure property is set for functions with empty bodies.
        state.funct["(isStrict)"] = state.isStrict();
      }

      advance("}", t);

      if (isfunc) {
        state.funct["(scope)"].validateParams(isfatarrow);
        if (m) {
          state.directive = m;
        }
      }

      state.funct["(scope)"].unstack();

      indent = old_indent;
    } else if (!ordinary) {
      if (isfunc) {
        state.funct["(scope)"].stack();

        if (stmt && !isfatarrow && !state.inMoz()) {
          error("W118", state.tokens.curr, "function closure expressions");
        }

        if (isfatarrow) {
          state.funct["(scope)"].validateParams(true);
        }

        var expr = expression(context, 10);

        if (state.option.noreturnawait && context & prodParams.async &&
            expr.identifier && expr.value === "await") {
          warning("W146", expr);
        }

        if (state.option.strict && state.funct["(context)"]["(global)"]) {
          if (!state.isStrict()) {
            warning("E007");
          }
        }

        state.funct["(scope)"].unstack();
      } else {
        error("E021", state.tokens.next, "{", state.tokens.next.value);
      }
    } else {

      state.funct["(scope)"].stack();

      if (!stmt || state.option.curly) {
        warning("W116", state.tokens.next, "{", state.tokens.next.value);
      }

      // JSHint observes Annex B of the ECMAScript specification by default,
      // where function declarations are permitted in the statement positions
      // of IfStatements.
      var supportsFnDecl = state.funct["(verb)"] === "if" ||
        state.tokens.curr.id === "else";

      state.tokens.next.inBracelessBlock = true;
      indent += state.option.indent;
      // test indentation only if statement is in new line
      a = [statement(context)];
      indent -= state.option.indent;

      if (a[0] && a[0].declaration &&
        !(supportsFnDecl && a[0].id === "function")) {
        error("E048", a[0], a[0].id[0].toUpperCase() + a[0].id.slice(1));
      }

      state.funct["(scope)"].unstack();
    }

    // Don't clear and let it propagate out if it is "break", "return" or
    // similar in switch case
    switch (state.funct["(verb)"]) {
    case "break":
    case "continue":
    case "return":
    case "throw":
      if (iscase) {
        break;
      }

      /* falls through */
    default:
      state.funct["(verb)"] = null;
    }

    inblock = b;
    if (ordinary && state.option.noempty && (!a || a.length === 0)) {
      warning("W035", state.tokens.prev);
    }
    metrics.nestedBlockDepth -= 1;
    return a;
  }


  /**
   * Update the global state which tracks all statically-identifiable property
   * names, and emit a warning if the `members` linting directive is in use and
   * does not include the given name.
   *
   * @param {string} m - the property name
   */
  function countMember(m) {
    if (membersOnly && typeof membersOnly[m] !== "boolean") {
      warning("W036", state.tokens.curr, m);
    }
    if (typeof member[m] === "number") {
      member[m] += 1;
    } else {
      member[m] = 1;
    }
  }

  // Build the syntax table by declaring the syntactic elements of the language.

  type("(number)", function() {
    if (state.tokens.next.id === ".") {
      warning("W005", this);
    }

    return this;
  });

  type("(string)", function() {
    return this;
  });

  state.syntax["(identifier)"] = {
    type: "(identifier)",
    lbp: 0,
    identifier: true,

    nud: function(context) {
      var v = this.value;

      // If this identifier is the lone parameter to a shorthand "fat arrow"
      // function definition, i.e.
      //
      //     x => x;
      //
      // ...it should not be considered as a variable in the current scope. It
      // will be added to the scope of the new function when the next token is
      // parsed, so it can be safely ignored for now.
      if (state.tokens.next.id === "=>") {
        return this;
      }

      if (isReserved(context, this)) {
        warning("W024", this, v);
      } else if (!state.funct["(comparray)"].check(v)) {
        state.funct["(scope)"].block.use(v, state.tokens.curr);
      }
      return this;
    },

    led: function() {
      /* istanbul ignore next */
      error("E033", state.tokens.next, state.tokens.next.value);
    }
  };

  var baseTemplateSyntax = {
    identifier: false,
    template: true,
  };
  state.syntax["(template)"] = _.extend({
    lbp: 155,
    type: "(template)",
    nud: doTemplateLiteral,
    led: doTemplateLiteral,
    noSubst: false
  }, baseTemplateSyntax);

  state.syntax["(template middle)"] = _.extend({
    lbp: 0,
    type: "(template middle)",
    noSubst: false
  }, baseTemplateSyntax);

  state.syntax["(template tail)"] = _.extend({
    lbp: 0,
    type: "(template tail)",
    tail: true,
    noSubst: false
  }, baseTemplateSyntax);

  state.syntax["(no subst template)"] = _.extend({
    lbp: 155,
    type: "(template)",
    nud: doTemplateLiteral,
    led: doTemplateLiteral,
    noSubst: true,
    tail: true // mark as tail, since it's always the last component
  }, baseTemplateSyntax);

  type("(regexp)", function() {
    return this;
  });

  // ECMAScript parser

  delim("(endline)");
  (function(x) {
    x.line = x.from = 0;
  })(delim("(begin)"));
  delim("(end)").reach = true;
  delim("(error)").reach = true;
  delim("}").reach = true;
  delim(")");
  delim("]");
  delim("\"").reach = true;
  delim("'").reach = true;
  delim(";");
  delim(":").reach = true;
  delim("#");

  reserve("else");
  reserve("case").reach = true;
  reserve("catch");
  reserve("default").reach = true;
  reserve("finally");
  reserve("true", function() { return this; });
  reserve("false", function() { return this; });
  reserve("null", function() { return this; });
  reserve("this", function() {
    if (state.isStrict() && !isMethod() &&
        !state.option.validthis && ((state.funct["(statement)"] &&
        state.funct["(name)"].charAt(0) > "Z") || state.funct["(global)"])) {
      warning("W040", this);
    }

    return this;
  });
  reserve("super", function() {
    superNud.call(state.tokens.curr, this);

    return this;
  });

  assignop("=", "assign", 20);
  assignop("+=", "assignadd", 20);
  assignop("-=", "assignsub", 20);
  assignop("*=", "assignmult", 20);
  assignop("/=", "assigndiv", 20).nud = function() {
    /* istanbul ignore next */
    error("E014");
  };
  assignop("%=", "assignmod", 20);
  assignop("**=", function(context, left, that) {
    if (!state.inES7()) {
      warning("W119", that, "Exponentiation operator", "7");
    }

    that.left = left;

    checkLeftSideAssign(context, left, that);

    that.right = expression(context, 10);

    return that;
  }, 20);

  bitwiseassignop("&=");
  bitwiseassignop("|=");
  bitwiseassignop("^=");
  bitwiseassignop("<<=");
  bitwiseassignop(">>=");
  bitwiseassignop(">>>=");
  infix(",", function(context, left, that) {
    var expr;
    that.exprs = [left];

    if (state.option.nocomma) {
      warning("W127");
    }

    if (!parseComma({ peek: true })) {
      return that;
    }
    while (true) {
      if (!(expr = expression(context, 10))) {
        /* istanbul ignore next */
        break;
      }
      that.exprs.push(expr);
      if (state.tokens.next.value !== "," || !parseComma()) {
        break;
      }
    }
    return that;
  }, 10, true);

  infix("?", function(context, left, that) {
    increaseComplexityCount();
    that.left = left;
    that.right = expression(context & ~prodParams.noin, 10);
    advance(":");
    expression(context, 10);
    return that;
  }, 30);

  var orPrecendence = 40;
  infix("||", function(context, left, that) {
    increaseComplexityCount();
    that.left = left;
    that.right = expression(context, orPrecendence);
    return that;
  }, orPrecendence);
  infix("&&", "and", 50);
  // The Exponentiation operator, introduced in ECMAScript 2016
  //
  // ExponentiationExpression[Yield] :
  //   UnaryExpression[?Yield]
  //   UpdateExpression[?Yield] ** ExponentiationExpression[?Yield]
  infix("**", function(context, left, that) {
    if (!state.inES7()) {
      warning("W119", that, "Exponentiation operator", "7");
    }

    // Disallow UnaryExpressions which are not wrapped in parenthesis
    if (!left.paren && beginsUnaryExpression(left)) {
      error("E024", that, "**");
    }

    that.left = left;
    that.right = expression(context, that.rbp);
    return that;
  }, 150);
  state.syntax["**"].rbp = 140;
  bitwise("|", "bitor", 70);
  bitwise("^", "bitxor", 80);
  bitwise("&", "bitand", 90);
  relation("==", function(context, left, right) {
    var eqnull = state.option.eqnull &&
      ((left && left.value) === "null" || (right && right.value) === "null");

    switch (true) {
      case !eqnull && state.option.eqeqeq:
        this.from = this.character;
        warning("W116", this, "===", "==");
        break;
      case isTypoTypeof(right, left, state):
        /* istanbul ignore next */
        warning("W122", this, right.value);
        /* istanbul ignore next */
        break;
      case isTypoTypeof(left, right, state):
        warning("W122", this, left.value);
        break;
    }

    return this;
  });
  relation("===", function(context, left, right) {
    if (isTypoTypeof(right, left, state)) {
      warning("W122", this, right.value);
    } else if (isTypoTypeof(left, right, state)) {
      /* istanbul ignore next */
      warning("W122", this, left.value);
    }
    return this;
  });
  relation("!=", function(context, left, right) {
    var eqnull = state.option.eqnull &&
        ((left && left.value) === "null" || (right && right.value) === "null");

    if (!eqnull && state.option.eqeqeq) {
      this.from = this.character;
      warning("W116", this, "!==", "!=");
    } else if (isTypoTypeof(right, left, state)) {
      /* istanbul ignore next */
      warning("W122", this, right.value);
    } else if (isTypoTypeof(left, right, state)) {
      warning("W122", this, left.value);
    }
    return this;
  });
  relation("!==", function(context, left, right) {
    if (isTypoTypeof(right, left, state)) {
      warning("W122", this, right.value);
    } else if (isTypoTypeof(left, right, state)) {
      /* istanbul ignore next */
      warning("W122", this, left.value);
    }
    return this;
  });
  relation("<");
  relation(">");
  relation("<=");
  relation(">=");
  bitwise("<<", "shiftleft", 120);
  bitwise(">>", "shiftright", 120);
  bitwise(">>>", "shiftrightunsigned", 120);
  infix("in", "in", 120);
  infix("instanceof", function(context, left, token) {
    var right;
    var scope = state.funct["(scope)"];
    token.left = left;
    token.right = right = expression(context, 120);

    // This condition reflects a syntax error which will be reported by the
    // `expression` function.
    if (!right) {
      return token;
    }

    if (right.id === "(number)" ||
        right.id === "(string)" ||
        right.value === "null" ||
        (right.value === "undefined" && !scope.has("undefined")) ||
        right.arity === "unary" ||
        right.id === "{" ||
        (right.id === "[" && !right.right) ||
        right.id === "(regexp)" ||
        (right.id === "(template)" && !right.tag)) {
      error("E060");
    }

    if (right.id === "function") {
      warning("W139");
    }

    return token;
  }, 120);
  infix("+", function(context, left, that) {
    var next = state.tokens.next;
    var right;
    that.left = left;
    that.right = right = expression(context, 130);

    if (left && right && left.id === "(string)" && right.id === "(string)") {
      left.value += right.value;
      left.character = right.character;
      if (!state.option.scripturl && reg.javascriptURL.test(left.value)) {
        warning("W050", left);
      }
      return left;
    }

    if (next.id === "+" || next.id === "++") {
      warning("W007", that.right);
    }

    return that;
  }, 130);
  prefix("+", function(context) {
    var next = state.tokens.next;
    this.arity = "unary";
    this.right = expression(context, 150);

    if (next.id === "+" || next.id === "++") {
      warning("W007", this.right);
    }

    return this;
  });
  infix("-", function(context, left, that) {
    var next = state.tokens.next;
    that.left = left;
    that.right = expression(context, 130);

    if (next.id === "-" || next.id === "--") {
      warning("W006", that.right);
    }

    return that;
  }, 130);
  prefix("-", function(context) {
    var next = state.tokens.next;
    this.arity = "unary";
    this.right = expression(context, 150);

    if (next.id === "-" || next.id === "--") {
      warning("W006", this.right);
    }

    return this;
  });
  infix("*", "mult", 140);
  infix("/", "div", 140);
  infix("%", "mod", 140);

  suffix("++");
  prefix("++", "preinc");
  state.syntax["++"].exps = true;
  state.syntax["++"].ltBoundary = "before";

  suffix("--");
  prefix("--", "predec");
  state.syntax["--"].exps = true;
  state.syntax["--"].ltBoundary = "before";

  prefix("delete", function(context) {
    this.arity = "unary";
    var p = expression(context, 150);
    if (!p) {
      return this;
    }

    if (p.id !== "." && p.id !== "[") {
      warning("W051");
    }
    this.first = p;

    // The `delete` operator accepts unresolvable references when not in strict
    // mode, so the operand may be undefined.
    if (p.identifier && !state.isStrict()) {
      p.forgiveUndef = true;
    }
    return this;
  }).exps = true;

  prefix("~", function(context) {
    if (state.option.bitwise) {
      warning("W016", this, "~");
    }
    this.arity = "unary";
    this.right = expression(context, 150);
    return this;
  });

  infix("...");

  prefix("!", function(context) {
    this.arity = "unary";
    this.right = expression(context, 150);

    if (!this.right) { // '!' followed by nothing? Give up.
      /* istanbul ignore next */
      quit("E041", this);
    }

    if (bang[this.right.id] === true) {
      /* istanbul ignore next */
      warning("W018", this, "!");
    }
    return this;
  });

  prefix("typeof", function(context) {
    this.arity = "unary";
    var p = expression(context, 150);
    this.first = this.right = p;

    if (!p) { // 'typeof' followed by nothing? Give up.
      quit("E041", this);
    }

    // The `typeof` operator accepts unresolvable references, so the operand
    // may be undefined.
    if (p.identifier) {
      p.forgiveUndef = true;
    }
    return this;
  });
  prefix("new", function(context) {
    var mp = metaProperty(context, "target", function() {
      if (!state.inES6(true)) {
        warning("W119", state.tokens.prev, "new.target", "6");
      }
      var inFunction, c = state.funct;
      while (c) {
        inFunction = !c["(global)"];
        if (!c["(arrow)"]) { break; }
        c = c["(context)"];
      }
      if (!inFunction) {
        warning("W136", state.tokens.prev, "new.target");
      }
    });
    if (mp) { return mp; }

    var c = expression(context, 155), i;
    if (c && c.id !== "function") {
      if (c.identifier) {
        switch (c.value) {
        case "Number":
        case "String":
        case "Boolean":
        case "Math":
        case "JSON":
          warning("W053", state.tokens.prev, c.value);
          break;
        case "Symbol":
          if (state.inES6()) {
            warning("W053", state.tokens.prev, c.value);
          }
          break;
        case "Function":
          if (!state.option.evil) {
            warning("W054");
          }
          break;
        case "Date":
        case "RegExp":
        case "this":
          break;
        default:
          i = c.value.substr(0, 1);
          if (state.option.newcap && (i < "A" || i > "Z") &&
            !state.funct["(scope)"].isPredefined(c.value)) {
            warning("W055", state.tokens.curr);
          }
        }
      } else {
        if (c.id !== "." && c.id !== "[" && c.id !== "(") {
          /* istanbul ignore next */
          warning("W056", state.tokens.curr);
        }
      }
    } else {
      if (!state.option.supernew)
        warning("W057", this);
    }
    if (state.tokens.next.id !== "(" && !state.option.supernew) {
      warning("W058", state.tokens.curr, state.tokens.curr.value);
    }
    this.first = this.right = c;
    return this;
  });
  state.syntax["new"].exps = true;


  // Class statement
  blockstmt("class", function(context) {
    var className, classNameToken;
    var inexport = context & prodParams.export;

    if (!state.inES6()) {
      warning("W104", state.tokens.curr, "class", "6");
    }
    state.inClassBody = true;

    // Class Declaration: 'class <Classname>'
    if (state.tokens.next.identifier && state.tokens.next.value !== "extends") {
      classNameToken = state.tokens.next;
      className = classNameToken.value;
      identifier(context);
      // unintialized, so that the 'extends' clause is parsed while the class is in TDZ
      state.funct["(scope)"].addlabel(className, {
        type: "class",
        initialized: false,
        token: classNameToken
      });
    }

    // Class Declaration: 'class <Classname> extends <Superclass>'
    if (state.tokens.next.value === "extends") {
      advance("extends");
      expression(context, 0);
    }

    if (classNameToken) {
      this.name = className;
      state.funct["(scope)"].initialize(className);
      if (inexport) {
        state.funct["(scope)"].setExported(className, classNameToken);
      }
    }
    state.funct["(scope)"].stack();
    classBody(this, context);
    return this;
  }).exps = true;

  /*
    Class expression

    The Block- and Expression- handling for "class" are almost identical, except for the ordering of steps.
    In an expression:, the name should not be saved into the calling scope, but is still accessible inside the definition, so we open a new scope first, then save the name. We also mark it as used.
  */
  prefix("class", function(context) {
    var className, classNameToken;

    if (!state.inES6()) {
      warning("W104", state.tokens.curr, "class", "6");
    }
    state.inClassBody = true;

    // Class Declaration: 'class <Classname>'
    if (state.tokens.next.identifier && state.tokens.next.value !== "extends") {
      classNameToken = state.tokens.next;
      className = classNameToken.value;
      identifier(context);
    }

    // Class Declaration: 'class <Classname> extends <Superclass>'
    if (state.tokens.next.value === "extends") {
      advance("extends");
      expression(context, 0);
    }

    state.funct["(scope)"].stack();
    if (classNameToken) {
      this.name = className;
      state.funct["(scope)"].addlabel(className, {
        type: "class",
        initialized: true,
        token: classNameToken
      });
      state.funct["(scope)"].block.use(className, classNameToken);
    }

    classBody(this, context);
    return this;
  });

  function classBody(classToken, context) {
    var props = Object.create(null);
    var name, accessorType, token, isStatic, inGenerator, hasConstructor;

    if (state.tokens.next.value === "{") {
      advance("{");
    } else {
      /* istanbul ignore next */
      warning("W116", state.tokens.curr, "identifier", state.tokens.next.type); //?
      /* istanbul ignore next */
      advance();
    }

    while (state.tokens.next.value !== "}") {
      isStatic = false;
      inGenerator = false;
      context &= ~prodParams.preAsync;

      if (state.tokens.next.value === "static") {
        isStatic = true;
        advance();
      }

      if (state.tokens.next.value === "async") {
        if (!checkPunctuator(peek(), "(")) {
          context |= prodParams.preAsync;
          advance();

          nolinebreak(state.tokens.curr);

          if (checkPunctuator(state.tokens.next, "*")) {
            inGenerator = true;
            advance("*");

            if (!state.inES9()) {
              warning("W119", state.tokens.next, "async generators", "9");
            }
          }

          if (!state.inES8()) {
            warning("W119", state.tokens.curr, "async functions", "8");
          }
        }
      }

      if (state.tokens.next.value === "*") {
        inGenerator = true;
        advance();
      }

      token = state.tokens.next;

      if ((token.value === "set" || token.value === "get") && !checkPunctuator(peek(), "(")) {
        if (inGenerator) {
          /* istanbul ignore next */
          error("E024", token, token.value);
        }
        accessorType = token.value;
        advance();
        token = state.tokens.next;

        if (!isStatic && token.value === "constructor") {
          error("E049", token, "class " + accessorType + "ter method", token.value);
        } else if (isStatic && token.value === "prototype") {
          error("E049", token, "static class " + accessorType + "ter method", token.value);
        }
      } else {
        accessorType = null;
      }

      switch (token.value) {
        case ";":
          warning("W032", token);
          advance();
          break;
        case "constructor":
          if (isStatic) {
            // treat like a regular method -- static methods can be called 'constructor'
            name = propertyName(context);
            saveProperty(props, name, token, true, isStatic);
            doMethod(classToken, context, name, inGenerator);
          } else {
            if (inGenerator || context & prodParams.preAsync) {
              error("E024", token, token.value);
            } else if (hasConstructor) {
              /* istanbul ignore next */
              error("E024", token, token.value);
            } else {
              hasConstructor = !accessorType && !isStatic;
            }
            advance();
            doMethod(classToken, context, state.nameStack.infer());
          }
          break;
        case "[":
          name = computedPropertyName(context);
          doMethod(classToken, context, name, inGenerator);
          // We don't check names (via calling saveProperty()) of computed expressions like ["Symbol.iterator"]()
          break;
        default:
          name = propertyName(context);
          if (name === undefined) {
            error("E024", token, token.value);
            advance();
            break;
          }

          if (accessorType) {
            saveAccessor(accessorType, props, name, token, true, isStatic);
            name = state.nameStack.infer();
          } else {
            if (isStatic && name === "prototype") {
              error("E049", token, "static class method", name);
            }

            saveProperty(props, name, token, true, isStatic);
          }

          doMethod(classToken, context, name, inGenerator);
          break;
      }
    }
    advance("}");
    checkProperties(props);

    state.inClassBody = false;
    state.funct["(scope)"].unstack();
  }

  function doMethod(classToken, context, name, generator) {
    if (generator) {
      if (!state.inES6()) {
        warning("W119", state.tokens.curr, "function*", "6");
      }
    }

    if (state.tokens.next.value !== "(") {
      error("E054", state.tokens.next, state.tokens.next.value);
      advance();
      if (state.tokens.next.value === "{") {
        // manually cheating the test "invalidClasses", which asserts this particular behavior when a class is misdefined.
        advance();
        if (state.tokens.next.value === "}") {
          warning("W116", state.tokens.next, "(", state.tokens.next.value);
          advance();
          identifier(context);
          advance();
        }
        /* istanbul ignore next */
        return;
      } else {
        while (state.tokens.next.value !== "(") {
          advance();
        }
      }
    }

    doFunction(context, { name: name,
        type: generator ? "generator" : null,
        isMethod: true,
        statement: classToken });
  }

  prefix("void").exps = true;

  infix(".", function(context, left, that) {
    var m = identifier(context, true);

    if (typeof m === "string") {
      countMember(m);
    }

    that.left = left;
    that.right = m;

    if (m && m === "hasOwnProperty" && state.tokens.next.value === "=") {
      warning("W001");
    }

    if (left && left.value === "arguments" && (m === "callee" || m === "caller")) {
      if (state.option.noarg)
        warning("W059", left, m);
      else if (state.isStrict())
        error("E008");
    } else if (!state.option.evil && left && left.value === "document" &&
        (m === "write" || m === "writeln")) {
      warning("W060", left);
    }

    if (!state.option.evil && (m === "eval" || m === "execScript")) {
      if (isGlobalEval(left, state)) {
        warning("W061");
      }
    }

    return that;
  }, 160, true);

  infix("(", function(context, left, that) {
    if (state.option.immed && left && !left.immed && left.id === "function") {
      warning("W062");
    }

    if (state.option.asi && checkPunctuators(state.tokens.prev, [")", "]"]) &&
      state.tokens.prev.line !== startLine(state.tokens.curr)) {
      warning("W014", state.tokens.curr, state.tokens.curr.id);
    }

    var n = 0;
    var p = [];

    if (left) {
      if (left.type === "(identifier)") {
        if (left.value.match(/^[A-Z]([A-Z0-9_$]*[a-z][A-Za-z0-9_$]*)?$/)) {
          if ("Array Number String Boolean Date Object Error Symbol".indexOf(left.value) === -1) {
            if (left.value === "Math") {
              /* istanbul ignore next */
              warning("W063", left);
            } else if (state.option.newcap) {
              warning("W064", left);
            }
          }
        }
      }
    }

    if (state.tokens.next.id !== ")") {
      for (;;) {
        spreadrest("spread");

        p[p.length] = expression(context, 10);
        n += 1;
        if (state.tokens.next.id !== ",") {
          break;
        }
        parseComma({ allowTrailing: true });

        if (state.tokens.next.id === ")") {
          if (!state.inES8()) {
            warning("W119", state.tokens.curr, "Trailing comma in arguments lists", "8");
          }

          break;
        }
      }
    }

    advance(")");

    if (typeof left === "object") {
      if (!state.inES5() && left.value === "parseInt" && n === 1) {
        warning("W065", state.tokens.curr);
      }
      if (!state.option.evil) {
        if (left.value === "eval" || left.value === "Function" ||
            left.value === "execScript") {
          warning("W061", left);

          // This conditional expression was initially implemented with a typo
          // which prevented the branch's execution in all cases. While
          // enabling the code will produce behavior that is consistent with
          // the other forms of code evaluation that follow, such a change is
          // also technically incompatable with prior versions of JSHint (due
          // to the fact that the behavior was never formally documented). This
          // branch should be enabled as part of a major release.
          //if (p[0] && p[0].id === "(string)") {
          //  addEvalCode(left, p[0]);
          //}
        } else if (p[0] && p[0].id === "(string)" &&
             (left.value === "setTimeout" ||
            left.value === "setInterval")) {
          warning("W066", left);
          addEvalCode(left, p[0]);

        // window.setTimeout/setInterval
        } else if (p[0] && p[0].id === "(string)" &&
             left.value === "." &&
             left.left.value === "window" &&
             (left.right === "setTimeout" ||
            left.right === "setInterval")) {
          warning("W066", left);
          addEvalCode(left, p[0]);
        }
      }
      if (!left.identifier && left.id !== "." && left.id !== "[" && left.id !== "=>" &&
          left.id !== "(" && left.id !== "&&" && left.id !== "||" && left.id !== "?" &&
          left.id !== "async" && !(state.inES6() && left["(name)"])) {
        warning("W067", that);
      }
    }

    that.left = left;
    return that;
  }, 155, true).exps = true;

  function peekThroughParens(parens) {
    var pn = state.tokens.next;
    var i = -1;
    var pn1;

    do {
      if (pn.value === "(") {
        parens += 1;
      } else if (pn.value === ")") {
        parens -= 1;
      }

      i += 1;
      pn1 = pn;
      pn = peek(i);
    } while (!(parens === 0 && pn1.value === ")") && pn.type !== "(end)");

    return pn;
  }

  prefix("(", function(context, rbp) {
    var ret, triggerFnExpr, first, last;
    var opening = state.tokens.curr;
    var preceeding = state.tokens.prev;
    var isNecessary = !state.option.singleGroups;
    var pn = peekThroughParens(1);

    if (state.tokens.next.id === "function") {
      triggerFnExpr = state.tokens.next.immed = true;
    }

    // If the balanced grouping operator is followed by a "fat arrow", the
    // current token marks the beginning of a "fat arrow" function and parsing
    // should proceed accordingly.
    if (pn.value === "=>") {
      pn.funct = doFunction(context, { type: "arrow", parsedOpening: true });
      return pn;
    }

    var exprs = [];

    if (state.tokens.next.id !== ")") {
      for (;;) {
        exprs.push(expression(context, 10));

        if (state.tokens.next.id !== ",") {
          break;
        }

        if (state.option.nocomma) {
          warning("W127");
        }

        parseComma();
      }
    }

    advance(")", this);
    if (state.option.immed && exprs[0] && exprs[0].id === "function") {
      if (state.tokens.next.id !== "(" &&
        state.tokens.next.id !== "." && state.tokens.next.id !== "[") {
        warning("W068", this);
      }
    }

    if (!exprs.length) {
      return;
    }
    if (exprs.length > 1) {
      ret = Object.create(state.syntax[","]);
      ret.exprs = exprs;

      first = exprs[0];
      last = exprs[exprs.length - 1];
    } else {
      ret = first = last = exprs[0];

      if (!isNecessary) {
        isNecessary =
          // Used to distinguish from an ExpressionStatement which may not
          // begin with the `{` and `function` tokens
          (opening.beginsStmt && (ret.id === "{" || triggerFnExpr)) ||
          // Used to signal that a function expression is being supplied to
          // some other operator.
          (triggerFnExpr &&
            // For parenthesis wrapping a function expression to be considered
            // necessary, the grouping operator should be the left-hand-side of
            // some other operator--either within the parenthesis or directly
            // following them.
            (!isEndOfExpr() || state.tokens.prev.id !== "}")) ||
          // Used to demarcate an arrow function as the left-hand side of some
          // operator.
          (ret.id === "=>" && !isEndOfExpr()) ||
          // Used as the return value of a single-statement arrow function
          (ret.id === "{" && preceeding.id === "=>") ||
          // Used to cover a unary expression as the left-hand side of the
          // exponentiation operator
          (beginsUnaryExpression(ret) && state.tokens.next.id === "**") ||
          // Used to delineate an integer number literal from a dereferencing
          // punctuator (otherwise interpreted as a decimal point)
          (ret.type === "(number)" &&
            checkPunctuator(pn, ".") && /^\d+$/.test(ret.value)) ||
          // Used to wrap object destructuring assignment
          (opening.beginsStmt && ret.id === "=" && ret.left.id === "{");
      }
    }

    if (ret) {
      // The operator may be necessary to override the default binding power of
      // neighboring operators (whenever there is an operator in use within the
      // first expression *or* the current group contains multiple expressions)
      if (!isNecessary && (isOperator(first) || ret.exprs)) {
        isNecessary =
          (rbp > first.lbp) ||
          (rbp > 0 && rbp === first.lbp) ||
          (!isEndOfExpr() && last.rbp < state.tokens.next.lbp);
      }

      if (!isNecessary) {
        warning("W126", opening);
      }

      ret.paren = true;
    }

    return ret;
  });

  application("=>");

  infix("[", function(context, left, that) {
    var e, s, canUseDot;

    if (state.option.asi && checkPunctuators(state.tokens.prev, [")", "]"]) &&
      state.tokens.prev.line !== startLine(state.tokens.curr)) {
      warning("W014", state.tokens.curr, state.tokens.curr.id);
    }

    e = expression(context & ~prodParams.noin, 10);

    if (e && e.type === "(string)") {
      if (!state.option.evil && (e.value === "eval" || e.value === "execScript")) {
        if (isGlobalEval(left, state)) {
          warning("W061");
        }
      }

      countMember(e.value);
      if (!state.option.sub && reg.identifier.test(e.value)) {
        s = state.syntax[e.value];

        if (s) {
          canUseDot = !isReserved(context, s);
        } else {
          // This branch exists to preserve legacy behavior with version 2.9.5
          // and earlier. In those releases, `eval` and `arguments` were
          // incorrectly interpreted as reserved keywords, so Member
          // Expressions such as `object["eval"]` did not trigger warning W069.
          //
          // TODO: Remove in JSHint 3
          canUseDot = e.value !== "eval" && e.value !== "arguments";
        }

        if (canUseDot) {
          warning("W069", state.tokens.prev, e.value);
        }
      }
    }
    advance("]", that);

    if (e && e.value === "hasOwnProperty" && state.tokens.next.value === "=") {
      warning("W001");
    }

    that.left = left;
    that.right = e;
    return that;
  }, 160, true);

  function comprehensiveArrayExpression(context) {
    var res = {};
    res.exps = true;
    state.funct["(comparray)"].stack();

    // Handle reversed for expressions, used in spidermonkey
    var reversed = false;
    if (state.tokens.next.value !== "for") {
      reversed = true;
      if (!state.inMoz()) {
        warning("W116", state.tokens.next, "for", state.tokens.next.value);
      }
      state.funct["(comparray)"].setState("use");
      res.right = expression(context, 10);
    }

    advance("for");
    if (state.tokens.next.value === "each") {
      advance("each");
      if (!state.inMoz()) {
        warning("W118", state.tokens.curr, "for each");
      }
    }
    advance("(");
    state.funct["(comparray)"].setState("define");
    res.left = expression(context, 130);
    if (_.includes(["in", "of"], state.tokens.next.value)) {
      advance();
    } else {
      /* istanbul ignore next */
      error("E045", state.tokens.curr);
    }
    state.funct["(comparray)"].setState("generate");
    expression(context, 10);

    advance(")");
    if (state.tokens.next.value === "if") {
      advance("if");
      advance("(");
      state.funct["(comparray)"].setState("filter");
      expression(context, 10);
      advance(")");
    }

    if (!reversed) {
      state.funct["(comparray)"].setState("use");
      res.right = expression(context, 10);
    }

    advance("]");
    state.funct["(comparray)"].unstack();
    return res;
  }

  prefix("[", function(context) {
    var blocktype = lookupBlockType();
    if (blocktype.isCompArray) {
      if (!state.option.esnext && !state.inMoz()) {
        warning("W118", state.tokens.curr, "array comprehension");
      }
      return comprehensiveArrayExpression(context);
    } else if (blocktype.isDestAssign) {
      this.destructAssign = destructuringPattern(context, {
          openingParsed: true,
          assignment: true
        });
      return this;
    }
    var b = state.tokens.curr.line !== startLine(state.tokens.next);
    this.first = [];
    if (b) {
      indent += state.option.indent;
      if (state.tokens.next.from === indent + state.option.indent) {
        /* istanbul ignore next */
        indent += state.option.indent;
      }
    }
    while (state.tokens.next.id !== "(end)") {
      while (state.tokens.next.id === ",") {
        if (!state.option.elision) {
          if (!state.inES5()) {
            // Maintain compat with old options --- ES5 mode without
            // elision=true will warn once per comma
            warning("W070");
          } else {
            warning("W128");
            do {
              advance(",");
            } while (state.tokens.next.id === ",");
            continue;
          }
        }
        advance(",");
      }

      if (state.tokens.next.id === "]") {
        break;
      }

      spreadrest("spread");

      this.first.push(expression(context, 10));
      if (state.tokens.next.id === ",") {
        parseComma({ allowTrailing: true });
        if (state.tokens.next.id === "]" && !state.inES5()) {
          warning("W070", state.tokens.curr);
          break;
        }
      } else {
        if (state.option.trailingcomma && state.inES5()) {
          warningAt("W140", state.tokens.curr.line, state.tokens.curr.character);
        }
        break;
      }
    }
    if (b) {
      indent -= state.option.indent;
    }
    advance("]", this);
    return this;
  });


  function isMethod() {
    return !!state.funct["(method)"];
  }

  function propertyName(context, preserveOrToken) {
    var id;
    var preserve = true;
    if (typeof preserveOrToken === "object") {
      /* istanbul ignore next */
      id = preserveOrToken;
    } else {
      preserve = preserveOrToken;
      id = optionalidentifier(context, true, preserve);
    }

    if (!id) {
      if (state.tokens.next.id === "(string)") {
        id = state.tokens.next.value;
        if (!preserve) {
          advance();
        }
      } else if (state.tokens.next.id === "(number)") {
        id = state.tokens.next.value.toString();
        if (!preserve) {
          advance();
        }
      }
    } else if (typeof id === "object") {
      /* istanbul ignore next */
      if (id.id === "(string)" || id.id === "(identifier)") id = id.value;
      /* istanbul ignore next */
      else if (id.id === "(number)") id = id.value.toString();
    }

    if (id === "hasOwnProperty") {
      warning("W001");
    }

    return id;
  }

  /**
   * @param {Number} context The parsing context
   * @param {Object} [options]
   * @param {token} [options.loneArg] The argument to the function in cases
   *                                  where it was defined using the
   *                                  single-argument shorthand.
   * @param {bool} [options.parsedOpening] Whether the opening parenthesis has
   *                                       already been parsed.
   *
   * @returns {{ arity: number, params: Array.<string>, isSimple: boolean }}
   */
  function functionparams(context, options) {
    var next;
    var paramsIds = [];
    var ident;
    var tokens = [];
    var t;
    var pastDefault = false;
    var pastRest = false;
    var arity = 0;
    var loneArg = options && options.loneArg;
    var hasDestructuring = false;

    if (loneArg && loneArg.identifier === true) {
      state.funct["(scope)"].addParam(loneArg.value, loneArg);
      return { arity: 1, params: [ loneArg.value ], isSimple: true };
    }

    next = state.tokens.next;

    if (!options || !options.parsedOpening) {
      advance("(");
    }

    if (state.tokens.next.id === ")") {
      advance(")");
      return;
    }

    function addParam(addParamArgs) {
      state.funct["(scope)"].addParam.apply(state.funct["(scope)"], addParamArgs);
    }

    for (;;) {
      arity++;
      // are added to the param scope
      var currentParams = [];

      if (_.includes(["{", "["], state.tokens.next.id)) {
        hasDestructuring = true;
        tokens = destructuringPattern(context);
        for (t in tokens) {
          t = tokens[t];
          if (t.id) {
            paramsIds.push(t.id);
            currentParams.push([t.id, t.token]);
          }
        }
      } else {
        pastRest = spreadrest("rest");
        ident = identifier(context);

        if (ident) {
          paramsIds.push(ident);
          currentParams.push([ident, state.tokens.curr]);
        } else {
          // Skip invalid parameter.
          while (!checkPunctuators(state.tokens.next, [",", ")"])) advance();
        }
      }

      // It is valid to have a regular argument after a default argument
      // since undefined can be used for missing parameters. Still warn as it is
      // a possible code smell.
      if (pastDefault) {
        if (state.tokens.next.id !== "=") {
          error("W138", state.tokens.curr);
        }
      }
      if (state.tokens.next.id === "=") {
        if (!state.inES6()) {
          warning("W119", state.tokens.next, "default parameters", "6");
        }

        if (pastRest) {
          error("E062", state.tokens.next);
        }

        advance("=");
        pastDefault = true;
        expression(context, 10);
      }

      // now we have evaluated the default expression, add the variable to the param scope
      currentParams.forEach(addParam);
      if (state.tokens.next.id === ",") {
        if (pastRest) {
          warning("W131", state.tokens.next);
        }
        parseComma({ allowTrailing: true });
      }

      if (state.tokens.next.id === ")") {
        if (state.tokens.curr.id === "," && !state.inES8()) {
          warning("W119", state.tokens.curr, "Trailing comma in function parameters", "8");
        }

        advance(")", next);
        return {
          arity: arity,
          params: paramsIds,
          isSimple: !hasDestructuring && !pastRest && !pastDefault
        };
      }
    }
  }

  /**
   * Factory function for creating objects used to track statistics of function
   * literals.
   *
   * @param {string} name - the identifier name to associate with the function
   * @param {object} [token] - token responsible for creating the function
   *                           object
   * @param {object} [overwrites] - a collection of properties that should
   *                                override the corresponding default value of
   *                                the new "functor" object
   */
  function functor(name, token, overwrites) {
    var funct = {
      "(name)"      : name,
      "(breakage)"  : 0,
      "(loopage)"   : 0,
      // The strictness of the function body is tracked via a dedicated
      // property (as opposed to via the global `state` object) so that the
      // value can be referenced after the body has been fully parsed (i.e.
      // when validating the identifier used in function declarations and
      // function expressions).
      "(isStrict)"  : "unknown",

      "(global)"    : false,

      "(line)"      : null,
      "(character)" : null,
      "(metrics)"   : null,
      "(statement)" : null,
      "(context)"   : null,
      "(scope)"     : null,
      "(comparray)" : null,
      "(generator)" : null,
      "(arrow)"     : null,
      "(async)"     : null,
      "(params)"    : null
    };

    if (token) {
      _.extend(funct, {
        "(line)"     : token.line,

jshint / jshint / 2952

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