// file: testIntl.js
// Copyright (C) 2011 2012 Norbert Lindenberg. All rights reserved.
// Copyright (C) 2012 2013 Mozilla Corporation. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
description: |
    This file contains shared functions for the tests in the conformance test
    suite for the ECMAScript Internationalization API.
author: Norbert Lindenberg
---*/

/**
 */


/**
 * @description Calls the provided function for every service constructor in
 * the Intl object.
 * @param {Function} f the function to call for each service constructor in
 *   the Intl object.
 *   @param {Function} Constructor the constructor object to test with.
 */
function testWithIntlConstructors(f) {
  var constructors = ["Collator", "NumberFormat", "DateTimeFormat"];

  // Optionally supported Intl constructors.
  ["PluralRules"].forEach(function(constructor) {
    if (typeof Intl[constructor] === "function") {
      constructors[constructors.length] = constructor;
    }
  });

  constructors.forEach(function (constructor) {
    var Constructor = Intl[constructor];
    try {
      f(Constructor);
    } catch (e) {
      e.message += " (Testing with " + constructor + ".)";
      throw e;
    }
  });
}


/**
 * Taints a named data property of the given object by installing
 * a setter that throws an exception.
 * @param {object} obj the object whose data property to taint
 * @param {string} property the property to taint
 */
function taintDataProperty(obj, property) {
  Object.defineProperty(obj, property, {
    set: function(value) {
      $ERROR("Client code can adversely affect behavior: setter for " + property + ".");
    },
    enumerable: false,
    configurable: true
  });
}


/**
 * Taints a named method of the given object by replacing it with a function
 * that throws an exception.
 * @param {object} obj the object whose method to taint
 * @param {string} property the name of the method to taint
 */
function taintMethod(obj, property) {
  Object.defineProperty(obj, property, {
    value: function() {
      $ERROR("Client code can adversely affect behavior: method " + property + ".");
    },
    writable: true,
    enumerable: false,
    configurable: true
  });
}


/**
 * Taints the given properties (and similarly named properties) by installing
 * setters on Object.prototype that throw exceptions.
 * @param {Array} properties an array of property names to taint
 */
function taintProperties(properties) {
  properties.forEach(function (property) {
    var adaptedProperties = [property, "__" + property, "_" + property, property + "_", property + "__"];
    adaptedProperties.forEach(function (property) {
      taintDataProperty(Object.prototype, property);
    });
  });
}


/**
 * Taints the Array object by creating a setter for the property "0" and
 * replacing some key methods with functions that throw exceptions.
 */
function taintArray() {
  taintDataProperty(Array.prototype, "0");
  taintMethod(Array.prototype, "indexOf");
  taintMethod(Array.prototype, "join");
  taintMethod(Array.prototype, "push");
  taintMethod(Array.prototype, "slice");
  taintMethod(Array.prototype, "sort");
}


/**
 * Gets locale support info for the given constructor object, which must be one
 * of Intl constructors.
 * @param {object} Constructor the constructor for which to get locale support info
 * @return {object} locale support info with the following properties:
 *   supported: array of fully supported language tags
 *   byFallback: array of language tags that are supported through fallbacks
 *   unsupported: array of unsupported language tags
 */
function getLocaleSupportInfo(Constructor) {
  var languages = ["zh", "es", "en", "hi", "ur", "ar", "ja", "pa"];
  var scripts = ["Latn", "Hans", "Deva", "Arab", "Jpan", "Hant"];
  var countries = ["CN", "IN", "US", "PK", "JP", "TW", "HK", "SG"];

  var allTags = [];
  var i, j, k;
  var language, script, country;
  for (i = 0; i < languages.length; i++) {
    language = languages[i];
    allTags.push(language);
    for (j = 0; j < scripts.length; j++) {
      script = scripts[j];
      allTags.push(language + "-" + script);
      for (k = 0; k < countries.length; k++) {
        country = countries[k];
        allTags.push(language + "-" + script + "-" + country);
      }
    }
    for (k = 0; k < countries.length; k++) {
      country = countries[k];
      allTags.push(language + "-" + country);
    }
  }

  var supported = [];
  var byFallback = [];
  var unsupported = [];
  for (i = 0; i < allTags.length; i++) {
    var request = allTags[i];
    var result = new Constructor([request], {localeMatcher: "lookup"}).resolvedOptions().locale;
    if (request === result) {
      supported.push(request);
    } else if (request.indexOf(result) === 0) {
      byFallback.push(request);
    } else {
      unsupported.push(request);
    }
  }

  return {
    supported: supported,
    byFallback: byFallback,
    unsupported: unsupported
  };
}


/**
 * @description Tests whether locale is a String value representing a
 * structurally valid and canonicalized BCP 47 language tag, as defined in
 * sections 6.2.2 and 6.2.3 of the ECMAScript Internationalization API
 * Specification.
 * @param {String} locale the string to be tested.
 * @result {Boolean} whether the test succeeded.
 */
function isCanonicalizedStructurallyValidLanguageTag(locale) {

  /**
   * Regular expression defining BCP 47 language tags.
   *
   * Spec: RFC 5646 section 2.1.
   */
  var alpha = "[a-zA-Z]",
    digit = "[0-9]",
    alphanum = "(" + alpha + "|" + digit + ")",
    regular = "(art-lojban|cel-gaulish|no-bok|no-nyn|zh-guoyu|zh-hakka|zh-min|zh-min-nan|zh-xiang)",
    irregular = "(en-GB-oed|i-ami|i-bnn|i-default|i-enochian|i-hak|i-klingon|i-lux|i-mingo|i-navajo|i-pwn|i-tao|i-tay|i-tsu|sgn-BE-FR|sgn-BE-NL|sgn-CH-DE)",
    grandfathered = "(" + irregular + "|" + regular + ")",
    privateuse = "(x(-[a-z0-9]{1,8})+)",
    singleton = "(" + digit + "|[A-WY-Za-wy-z])",
    extension = "(" + singleton + "(-" + alphanum + "{2,8})+)",
    variant = "(" + alphanum + "{5,8}|(" + digit + alphanum + "{3}))",
    region = "(" + alpha + "{2}|" + digit + "{3})",
    script = "(" + alpha + "{4})",
    extlang = "(" + alpha + "{3}(-" + alpha + "{3}){0,2})",
    language = "(" + alpha + "{2,3}(-" + extlang + ")?|" + alpha + "{4}|" + alpha + "{5,8})",
    langtag = language + "(-" + script + ")?(-" + region + ")?(-" + variant + ")*(-" + extension + ")*(-" + privateuse + ")?",
    languageTag = "^(" + langtag + "|" + privateuse + "|" + grandfathered + ")$",
    languageTagRE = new RegExp(languageTag, "i");
  var duplicateSingleton = "-" + singleton + "-(.*-)?\\1(?!" + alphanum + ")",
    duplicateSingletonRE = new RegExp(duplicateSingleton, "i"),
    duplicateVariant = "(" + alphanum + "{2,8}-)+" + variant + "-(" + alphanum + "{2,8}-)*\\3(?!" + alphanum + ")",
    duplicateVariantRE = new RegExp(duplicateVariant, "i");


  /**
   * Verifies that the given string is a well-formed BCP 47 language tag
   * with no duplicate variant or singleton subtags.
   *
   * Spec: ECMAScript Internationalization API Specification, draft, 6.2.2.
   */
  function isStructurallyValidLanguageTag(locale) {
    if (!languageTagRE.test(locale)) {
      return false;
    }
    locale = locale.split(/-x-/)[0];
    return !duplicateSingletonRE.test(locale) && !duplicateVariantRE.test(locale);
  }


  /**
   * Mappings from complete tags to preferred values.
   *
   * Spec: IANA Language Subtag Registry.
   */
  var __tagMappings = {
    // property names must be in lower case; values in canonical form

    // grandfathered tags from IANA language subtag registry, file date 2017-12-14
    "art-lojban": "jbo",
    "cel-gaulish": "cel-gaulish",
    "en-gb-oed": "en-GB-oxendict",
    "i-ami": "ami",
    "i-bnn": "bnn",
    "i-default": "i-default",
    "i-enochian": "i-enochian",
    "i-hak": "hak",
    "i-klingon": "tlh",
    "i-lux": "lb",
    "i-mingo": "i-mingo",
    "i-navajo": "nv",
    "i-pwn": "pwn",
    "i-tao": "tao",
    "i-tay": "tay",
    "i-tsu": "tsu",
    "no-bok": "nb",
    "no-nyn": "nn",
    "sgn-be-fr": "sfb",
    "sgn-be-nl": "vgt",
    "sgn-ch-de": "sgg",
    "zh-guoyu": "cmn",
    "zh-hakka": "hak",
    "zh-min": "zh-min",
    "zh-min-nan": "nan",
    "zh-xiang": "hsn",
    // deprecated redundant tags from IANA language subtag registry, file date 2017-12-14
    "sgn-br": "bzs",
    "sgn-co": "csn",
    "sgn-de": "gsg",
    "sgn-dk": "dsl",
    "sgn-es": "ssp",
    "sgn-fr": "fsl",
    "sgn-gb": "bfi",
    "sgn-gr": "gss",
    "sgn-ie": "isg",
    "sgn-it": "ise",
    "sgn-jp": "jsl",
    "sgn-mx": "mfs",
    "sgn-ni": "ncs",
    "sgn-nl": "dse",
    "sgn-no": "nsl",
    "sgn-pt": "psr",
    "sgn-se": "swl",
    "sgn-us": "ase",
    "sgn-za": "sfs",
    "zh-cmn": "cmn",
    "zh-cmn-hans": "cmn-Hans",
    "zh-cmn-hant": "cmn-Hant",
    "zh-gan": "gan",
    "zh-wuu": "wuu",
    "zh-yue": "yue",
    // deprecated variant with prefix from IANA language subtag registry, file date 2017-12-14
    "ja-latn-hepburn-heploc": "ja-Latn-alalc97"
  };


  /**
   * Mappings from non-extlang subtags to preferred values.
   *
   * Spec: IANA Language Subtag Registry.
   */
  var __subtagMappings = {
    // property names and values must be in canonical case
    // language subtags with Preferred-Value mappings from IANA language subtag registry, file date 2017-12-14
    "in": "id",
    "iw": "he",
    "ji": "yi",
    "jw": "jv",
    "mo": "ro",
    "aam": "aas",
    "adp": "dz",
    "aue": "ktz",
    "ayx": "nun",
    "bgm": "bcg",
    "bjd": "drl",
    "ccq": "rki",
    "cjr": "mom",
    "cka": "cmr",
    "cmk": "xch",
    "coy": "pij",
    "cqu": "quh",
    "drh": "khk",
    "drw": "prs",
    "gav": "dev",
    "gfx": "vaj",
    "ggn": "gvr",
    "gti": "nyc",
    "guv": "duz",
    "hrr": "jal",
    "ibi": "opa",
    "ilw": "gal",
    "jeg": "oyb",
    "kgc": "tdf",
    "kgh": "kml",
    "koj": "kwv",
    "krm": "bmf",
    "ktr": "dtp",
    "kvs": "gdj",
    "kwq": "yam",
    "kxe": "tvd",
    "kzj": "dtp",
    "kzt": "dtp",
    "lii": "raq",
    "lmm": "rmx",
    "meg": "cir",
    "mst": "mry",
    "mwj": "vaj",
    "myt": "mry",
    "nad": "xny",
    "nnx": "ngv",
    "nts": "pij",
    "oun": "vaj",
    "pcr": "adx",
    "pmc": "huw",
    "pmu": "phr",
    "ppa": "bfy",
    "ppr": "lcq",
    "pry": "prt",
    "puz": "pub",
    "sca": "hle",
    "skk": "oyb",
    "tdu": "dtp",
    "thc": "tpo",
    "thx": "oyb",
    "tie": "ras",
    "tkk": "twm",
    "tlw": "weo",
    "tmp": "tyj",
    "tne": "kak",
    "tnf": "prs",
    "tsf": "taj",
    "uok": "ema",
    "xba": "cax",
    "xia": "acn",
    "xkh": "waw",
    "xsj": "suj",
    "ybd": "rki",
    "yma": "lrr",
    "ymt": "mtm",
    "yos": "zom",
    "yuu": "yug",
    // region subtags with Preferred-Value mappings from IANA language subtag registry, file date 2017-12-14
    "BU": "MM",
    "DD": "DE",
    "FX": "FR",
    "TP": "TL",
    "YD": "YE",
    "ZR": "CD"
  };


  /**
   * Mappings from extlang subtags to preferred values.
   *
   * Spec: IANA Language Subtag Registry.
   */
  var __extlangMappings = {
    // extlang subtags with Preferred-Value mappings from IANA language subtag registry, file date 2017-12-14
    // values are arrays with [0] the replacement value, [1] (if present) the prefix to be removed
    "aao": ["aao", "ar"],
    "abh": ["abh", "ar"],
    "abv": ["abv", "ar"],
    "acm": ["acm", "ar"],
    "acq": ["acq", "ar"],
    "acw": ["acw", "ar"],
    "acx": ["acx", "ar"],
    "acy": ["acy", "ar"],
    "adf": ["adf", "ar"],
    "ads": ["ads", "sgn"],
    "aeb": ["aeb", "ar"],
    "aec": ["aec", "ar"],
    "aed": ["aed", "sgn"],
    "aen": ["aen", "sgn"],
    "afb": ["afb", "ar"],
    "afg": ["afg", "sgn"],
    "ajp": ["ajp", "ar"],
    "apc": ["apc", "ar"],
    "apd": ["apd", "ar"],
    "arb": ["arb", "ar"],
    "arq": ["arq", "ar"],
    "ars": ["ars", "ar"],
    "ary": ["ary", "ar"],
    "arz": ["arz", "ar"],
    "ase": ["ase", "sgn"],
    "asf": ["asf", "sgn"],
    "asp": ["asp", "sgn"],
    "asq": ["asq", "sgn"],
    "asw": ["asw", "sgn"],
    "auz": ["auz", "ar"],
    "avl": ["avl", "ar"],
    "ayh": ["ayh", "ar"],
    "ayl": ["ayl", "ar"],
    "ayn": ["ayn", "ar"],
    "ayp": ["ayp", "ar"],
    "bbz": ["bbz", "ar"],
    "bfi": ["bfi", "sgn"],
    "bfk": ["bfk", "sgn"],
    "bjn": ["bjn", "ms"],
    "bog": ["bog", "sgn"],
    "bqn": ["bqn", "sgn"],
    "bqy": ["bqy", "sgn"],
    "btj": ["btj", "ms"],
    "bve": ["bve", "ms"],
    "bvl": ["bvl", "sgn"],
    "bvu": ["bvu", "ms"],
    "bzs": ["bzs", "sgn"],
    "cdo": ["cdo", "zh"],
    "cds": ["cds", "sgn"],
    "cjy": ["cjy", "zh"],
    "cmn": ["cmn", "zh"],
    "coa": ["coa", "ms"],
    "cpx": ["cpx", "zh"],
    "csc": ["csc", "sgn"],
    "csd": ["csd", "sgn"],
    "cse": ["cse", "sgn"],
    "csf": ["csf", "sgn"],
    "csg": ["csg", "sgn"],
    "csl": ["csl", "sgn"],
    "csn": ["csn", "sgn"],
    "csq": ["csq", "sgn"],
    "csr": ["csr", "sgn"],
    "czh": ["czh", "zh"],
    "czo": ["czo", "zh"],
    "doq": ["doq", "sgn"],
    "dse": ["dse", "sgn"],
    "dsl": ["dsl", "sgn"],
    "dup": ["dup", "ms"],
    "ecs": ["ecs", "sgn"],
    "esl": ["esl", "sgn"],
    "esn": ["esn", "sgn"],
    "eso": ["eso", "sgn"],
    "eth": ["eth", "sgn"],
    "fcs": ["fcs", "sgn"],
    "fse": ["fse", "sgn"],
    "fsl": ["fsl", "sgn"],
    "fss": ["fss", "sgn"],
    "gan": ["gan", "zh"],
    "gds": ["gds", "sgn"],
    "gom": ["gom", "kok"],
    "gse": ["gse", "sgn"],
    "gsg": ["gsg", "sgn"],
    "gsm": ["gsm", "sgn"],
    "gss": ["gss", "sgn"],
    "gus": ["gus", "sgn"],
    "hab": ["hab", "sgn"],
    "haf": ["haf", "sgn"],
    "hak": ["hak", "zh"],
    "hds": ["hds", "sgn"],
    "hji": ["hji", "ms"],
    "hks": ["hks", "sgn"],
    "hos": ["hos", "sgn"],
    "hps": ["hps", "sgn"],
    "hsh": ["hsh", "sgn"],
    "hsl": ["hsl", "sgn"],
    "hsn": ["hsn", "zh"],
    "icl": ["icl", "sgn"],
    "iks": ["iks", "sgn"],
    "ils": ["ils", "sgn"],
    "inl": ["inl", "sgn"],
    "ins": ["ins", "sgn"],
    "ise": ["ise", "sgn"],
    "isg": ["isg", "sgn"],
    "isr": ["isr", "sgn"],
    "jak": ["jak", "ms"],
    "jax": ["jax", "ms"],
    "jcs": ["jcs", "sgn"],
    "jhs": ["jhs", "sgn"],
    "jls": ["jls", "sgn"],
    "jos": ["jos", "sgn"],
    "jsl": ["jsl", "sgn"],
    "jus": ["jus", "sgn"],
    "kgi": ["kgi", "sgn"],
    "knn": ["knn", "kok"],
    "kvb": ["kvb", "ms"],
    "kvk": ["kvk", "sgn"],
    "kvr": ["kvr", "ms"],
    "kxd": ["kxd", "ms"],
    "lbs": ["lbs", "sgn"],
    "lce": ["lce", "ms"],
    "lcf": ["lcf", "ms"],
    "liw": ["liw", "ms"],
    "lls": ["lls", "sgn"],
    "lsg": ["lsg", "sgn"],
    "lsl": ["lsl", "sgn"],
    "lso": ["lso", "sgn"],
    "lsp": ["lsp", "sgn"],
    "lst": ["lst", "sgn"],
    "lsy": ["lsy", "sgn"],
    "ltg": ["ltg", "lv"],
    "lvs": ["lvs", "lv"],
    "lzh": ["lzh", "zh"],
    "max": ["max", "ms"],
    "mdl": ["mdl", "sgn"],
    "meo": ["meo", "ms"],
    "mfa": ["mfa", "ms"],
    "mfb": ["mfb", "ms"],
    "mfs": ["mfs", "sgn"],
    "min": ["min", "ms"],
    "mnp": ["mnp", "zh"],
    "mqg": ["mqg", "ms"],
    "mre": ["mre", "sgn"],
    "msd": ["msd", "sgn"],
    "msi": ["msi", "ms"],
    "msr": ["msr", "sgn"],
    "mui": ["mui", "ms"],
    "mzc": ["mzc", "sgn"],
    "mzg": ["mzg", "sgn"],
    "mzy": ["mzy", "sgn"],
    "nan": ["nan", "zh"],
    "nbs": ["nbs", "sgn"],
    "ncs": ["ncs", "sgn"],
    "nsi": ["nsi", "sgn"],
    "nsl": ["nsl", "sgn"],
    "nsp": ["nsp", "sgn"],
    "nsr": ["nsr", "sgn"],
    "nzs": ["nzs", "sgn"],
    "okl": ["okl", "sgn"],
    "orn": ["orn", "ms"],
    "ors": ["ors", "ms"],
    "pel": ["pel", "ms"],
    "pga": ["pga", "ar"],
    "pgz": ["pgz", "sgn"],
    "pks": ["pks", "sgn"],
    "prl": ["prl", "sgn"],
    "prz": ["prz", "sgn"],
    "psc": ["psc", "sgn"],
    "psd": ["psd", "sgn"],
    "pse": ["pse", "ms"],
    "psg": ["psg", "sgn"],
    "psl": ["psl", "sgn"],
    "pso": ["pso", "sgn"],
    "psp": ["psp", "sgn"],
    "psr": ["psr", "sgn"],
    "pys": ["pys", "sgn"],
    "rms": ["rms", "sgn"],
    "rsl": ["rsl", "sgn"],
    "rsm": ["rsm", "sgn"],
    "sdl": ["sdl", "sgn"],
    "sfb": ["sfb", "sgn"],
    "sfs": ["sfs", "sgn"],
    "sgg": ["sgg", "sgn"],
    "sgx": ["sgx", "sgn"],
    "shu": ["shu", "ar"],
    "slf": ["slf", "sgn"],
    "sls": ["sls", "sgn"],
    "sqk": ["sqk", "sgn"],
    "sqs": ["sqs", "sgn"],
    "ssh": ["ssh", "ar"],
    "ssp": ["ssp", "sgn"],
    "ssr": ["ssr", "sgn"],
    "svk": ["svk", "sgn"],
    "swc": ["swc", "sw"],
    "swh": ["swh", "sw"],
    "swl": ["swl", "sgn"],
    "syy": ["syy", "sgn"],
    "szs": ["szs", "sgn"],
    "tmw": ["tmw", "ms"],
    "tse": ["tse", "sgn"],
    "tsm": ["tsm", "sgn"],
    "tsq": ["tsq", "sgn"],
    "tss": ["tss", "sgn"],
    "tsy": ["tsy", "sgn"],
    "tza": ["tza", "sgn"],
    "ugn": ["ugn", "sgn"],
    "ugy": ["ugy", "sgn"],
    "ukl": ["ukl", "sgn"],
    "uks": ["uks", "sgn"],
    "urk": ["urk", "ms"],
    "uzn": ["uzn", "uz"],
    "uzs": ["uzs", "uz"],
    "vgt": ["vgt", "sgn"],
    "vkk": ["vkk", "ms"],
    "vkt": ["vkt", "ms"],
    "vsi": ["vsi", "sgn"],
    "vsl": ["vsl", "sgn"],
    "vsv": ["vsv", "sgn"],
    "wbs": ["wbs", "sgn"],
    "wuu": ["wuu", "zh"],
    "xki": ["xki", "sgn"],
    "xml": ["xml", "sgn"],
    "xmm": ["xmm", "ms"],
    "xms": ["xms", "sgn"],
    "ygs": ["ygs", "sgn"],
    "yhs": ["yhs", "sgn"],
    "ysl": ["ysl", "sgn"],
    "yue": ["yue", "zh"],
    "zib": ["zib", "sgn"],
    "zlm": ["zlm", "ms"],
    "zmi": ["zmi", "ms"],
    "zsl": ["zsl", "sgn"],
    "zsm": ["zsm", "ms"],
  };


  /**
   * Canonicalizes the given well-formed BCP 47 language tag, including regularized case of subtags.
   *
   * Spec: ECMAScript Internationalization API Specification, draft, 6.2.3.
   * Spec: RFC 5646, section 4.5.
   */
  function canonicalizeLanguageTag(locale) {

    // start with lower case for easier processing, and because most subtags will need to be lower case anyway
    locale = locale.toLowerCase();

    // handle mappings for complete tags
    if (__tagMappings.hasOwnProperty(locale)) {
      return __tagMappings[locale];
    }

    var subtags = locale.split("-");
    var i = 0;

    // handle standard part: all subtags before first singleton or "x"
    while (i < subtags.length) {
      var subtag = subtags[i];
      if (subtag.length === 1 && (i > 0 || subtag === "x")) {
        break;
      } else if (i !== 0 && subtag.length === 2) {
        subtag = subtag.toUpperCase();
      } else if (subtag.length === 4) {
        subtag = subtag[0].toUpperCase() + subtag.substring(1).toLowerCase();
      }
      if (__subtagMappings.hasOwnProperty(subtag)) {
        subtag = __subtagMappings[subtag];
      } else if (__extlangMappings.hasOwnProperty(subtag)) {
        subtag = __extlangMappings[subtag][0];
        if (i === 1 && __extlangMappings[subtag][1] === subtags[0]) {
          subtags.shift();
          i--;
        }
      }
      subtags[i] = subtag;
      i++;
    }
    var normal = subtags.slice(0, i).join("-");

    // handle extensions
    var extensions = [];
    while (i < subtags.length && subtags[i] !== "x") {
      var extensionStart = i;
      i++;
      while (i < subtags.length && subtags[i].length > 1) {
        i++;
      }
      var extension = subtags.slice(extensionStart, i).join("-");
      extensions.push(extension);
    }
    extensions.sort();

    // handle private use
    var privateUse;
    if (i < subtags.length) {
      privateUse = subtags.slice(i).join("-");
    }

    // put everything back together
    var canonical = normal;
    if (extensions.length > 0) {
      canonical += "-" + extensions.join("-");
    }
    if (privateUse !== undefined) {
      if (canonical.length > 0) {
        canonical += "-" + privateUse;
      } else {
        canonical = privateUse;
      }
    }

    return canonical;
  }

  return typeof locale === "string" && isStructurallyValidLanguageTag(locale) &&
      canonicalizeLanguageTag(locale) === locale;
}


/**
 * Tests whether the named options property is correctly handled by the given constructor.
 * @param {object} Constructor the constructor to test.
 * @param {string} property the name of the options property to test.
 * @param {string} type the type that values of the property are expected to have
 * @param {Array} [values] an array of allowed values for the property. Not needed for boolean.
 * @param {any} fallback the fallback value that the property assumes if not provided.
 * @param {object} testOptions additional options:
 *   @param {boolean} isOptional whether support for this property is optional for implementations.
 *   @param {boolean} noReturn whether the resulting value of the property is not returned.
 *   @param {boolean} isILD whether the resulting value of the property is implementation and locale dependent.
 *   @param {object} extra additional option to pass along, properties are value -> {option: value}.
 */
function testOption(Constructor, property, type, values, fallback, testOptions) {
  var isOptional = testOptions !== undefined && testOptions.isOptional === true;
  var noReturn = testOptions !== undefined && testOptions.noReturn === true;
  var isILD = testOptions !== undefined && testOptions.isILD === true;

  function addExtraOptions(options, value, testOptions) {
    if (testOptions !== undefined && testOptions.extra !== undefined) {
      var extra;
      if (value !== undefined && testOptions.extra[value] !== undefined) {
        extra = testOptions.extra[value];
      } else if (testOptions.extra.any !== undefined) {
        extra = testOptions.extra.any;
      }
      if (extra !== undefined) {
        Object.getOwnPropertyNames(extra).forEach(function (prop) {
          options[prop] = extra[prop];
        });
      }
    }
  }

  var testValues, options, obj, expected, actual, error;

  // test that the specified values are accepted. Also add values that convert to specified values.
  if (type === "boolean") {
    if (values === undefined) {
      values = [true, false];
    }
    testValues = values.slice(0);
    testValues.push(888);
    testValues.push(0);
  } else if (type === "string") {
    testValues = values.slice(0);
    testValues.push({toString: function () { return values[0]; }});
  }
  testValues.forEach(function (value) {
    options = {};
    options[property] = value;
    addExtraOptions(options, value, testOptions);
    obj = new Constructor(undefined, options);
    if (noReturn) {
      if (obj.resolvedOptions().hasOwnProperty(property)) {
        $ERROR("Option property " + property + " is returned, but shouldn't be.");
      }
    } else {
      actual = obj.resolvedOptions()[property];
      if (isILD) {
        if (actual !== undefined && values.indexOf(actual) === -1) {
          $ERROR("Invalid value " + actual + " returned for property " + property + ".");
        }
      } else {
        if (type === "boolean") {
          expected = Boolean(value);
        } else if (type === "string") {
          expected = String(value);
        }
        if (actual !== expected && !(isOptional && actual === undefined)) {
          $ERROR("Option value " + value + " for property " + property +
            " was not accepted; got " + actual + " instead.");
        }
      }
    }
  });

  // test that invalid values are rejected
  if (type === "string") {
    var invalidValues = ["invalidValue", -1, null];
    // assume that we won't have values in caseless scripts
    if (values[0].toUpperCase() !== values[0]) {
      invalidValues.push(values[0].toUpperCase());
    } else {
      invalidValues.push(values[0].toLowerCase());
    }
    invalidValues.forEach(function (value) {
      options = {};
      options[property] = value;
      addExtraOptions(options, value, testOptions);
      error = undefined;
      try {
        obj = new Constructor(undefined, options);
      } catch (e) {
        error = e;
      }
      if (error === undefined) {
        $ERROR("Invalid option value " + value + " for property " + property + " was not rejected.");
      } else if (error.name !== "RangeError") {
        $ERROR("Invalid option value " + value + " for property " + property + " was rejected with wrong error " + error.name + ".");
      }
    });
  }

  // test that fallback value or another valid value is used if no options value is provided
  if (!noReturn) {
    options = {};
    addExtraOptions(options, undefined, testOptions);
    obj = new Constructor(undefined, options);
    actual = obj.resolvedOptions()[property];
    if (!(isOptional && actual === undefined)) {
      if (fallback !== undefined) {
        if (actual !== fallback) {
          $ERROR("Option fallback value " + fallback + " for property " + property +
            " was not used; got " + actual + " instead.");
        }
      } else {
        if (values.indexOf(actual) === -1 && !(isILD && actual === undefined)) {
          $ERROR("Invalid value " + actual + " returned for property " + property + ".");
        }
      }
    }
  }
}


/**
 * Properties of the RegExp constructor that may be affected by use of regular
 * expressions, and the default values of these properties. Properties are from
 * https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Deprecated_and_obsolete_features#RegExp_Properties
 */
var regExpProperties = ["$1", "$2", "$3", "$4", "$5", "$6", "$7", "$8", "$9",
  "$_", "$*", "$&", "$+", "$`", "$'",
  "input", "lastMatch", "lastParen", "leftContext", "rightContext"
];

var regExpPropertiesDefaultValues = (function () {
  var values = Object.create(null);
  regExpProperties.forEach(function (property) {
    values[property] = RegExp[property];
  });
  return values;
}());


/**
 * Tests that executing the provided function (which may use regular expressions
 * in its implementation) does not create or modify unwanted properties on the
 * RegExp constructor.
 */
function testForUnwantedRegExpChanges(testFunc) {
  regExpProperties.forEach(function (property) {
    RegExp[property] = regExpPropertiesDefaultValues[property];
  });
  testFunc();
  regExpProperties.forEach(function (property) {
    if (RegExp[property] !== regExpPropertiesDefaultValues[property]) {
      $ERROR("RegExp has unexpected property " + property + " with value " +
        RegExp[property] + ".");
    }
  });
}


/**
 * Tests whether name is a valid BCP 47 numbering system name
 * and not excluded from use in the ECMAScript Internationalization API.
 * @param {string} name the name to be tested.
 * @return {boolean} whether name is a valid BCP 47 numbering system name and
 *   allowed for use in the ECMAScript Internationalization API.
 */

function isValidNumberingSystem(name) {

  // source: CLDR file common/bcp47/number.xml; version CLDR 32.
  var numberingSystems = [
    "adlm",
    "ahom",
    "arab",
    "arabext",
    "armn",
    "armnlow",
    "bali",
    "beng",
    "bhks",
    "brah",
    "cakm",
    "cham",
    "cyrl",
    "deva",
    "ethi",
    "finance",
    "fullwide",
    "geor",
    "gonm",
    "grek",
    "greklow",
    "gujr",
    "guru",
    "hanidays",
    "hanidec",
    "hans",
    "hansfin",
    "hant",
    "hantfin",
    "hebr",
    "hmng",
    "java",
    "jpan",
    "jpanfin",
    "kali",
    "khmr",
    "knda",
    "lana",
    "lanatham",
    "laoo",
    "latn",
    "lepc",
    "limb",
    "mathbold",
    "mathdbl",
    "mathmono",
    "mathsanb",
    "mathsans",
    "mlym",
    "modi",
    "mong",
    "mroo",
    "mtei",
    "mymr",
    "mymrshan",
    "mymrtlng",
    "native",
    "newa",
    "nkoo",
    "olck",
    "orya",
    "osma",
    "roman",
    "romanlow",
    "saur",
    "shrd",
    "sind",
    "sinh",
    "sora",
    "sund",
    "takr",
    "talu",
    "taml",
    "tamldec",
    "telu",
    "thai",
    "tirh",
    "tibt",
    "traditio",
    "vaii",
    "wara",
  ];

  var excluded = [
    "finance",
    "native",
    "traditio"
  ];


  return numberingSystems.indexOf(name) !== -1 && excluded.indexOf(name) === -1;
}


/**
 * Provides the digits of numbering systems with simple digit mappings,
 * as specified in 11.3.2.
 */

var numberingSystemDigits = {
  arab: "٠١٢٣٤٥٦٧٨٩",
  arabext: "۰۱۲۳۴۵۶۷۸۹",
  bali: "\u1B50\u1B51\u1B52\u1B53\u1B54\u1B55\u1B56\u1B57\u1B58\u1B59",
  beng: "০১২৩৪৫৬৭৮৯",
  deva: "०१२३४५६७८९",
  fullwide: "０１２３４５６７８９",
  gujr: "૦૧૨૩૪૫૬૭૮૯",
  guru: "੦੧੨੩੪੫੬੭੮੯",
  hanidec: "〇一二三四五六七八九",
  khmr: "០១២៣៤៥៦៧៨៩",
  knda: "೦೧೨೩೪೫೬೭೮೯",
  laoo: "໐໑໒໓໔໕໖໗໘໙",
  latn: "0123456789",
  limb: "\u1946\u1947\u1948\u1949\u194A\u194B\u194C\u194D\u194E\u194F",
  mlym: "൦൧൨൩൪൫൬൭൮൯",
  mong: "᠐᠑᠒᠓᠔᠕᠖᠗᠘᠙",
  mymr: "၀၁၂၃၄၅၆၇၈၉",
  orya: "୦୧୨୩୪୫୬୭୮୯",
  tamldec: "௦௧௨௩௪௫௬௭௮௯",
  telu: "౦౧౨౩౪౫౬౭౮౯",
  thai: "๐๑๒๓๔๕๖๗๘๙",
  tibt: "༠༡༢༣༤༥༦༧༨༩"
};


/**
 * Tests that number formatting is handled correctly. The function checks that the
 * digit sequences in formatted output are as specified, converted to the
 * selected numbering system, and embedded in consistent localized patterns.
 * @param {Array} locales the locales to be tested.
 * @param {Array} numberingSystems the numbering systems to be tested.
 * @param {Object} options the options to pass to Intl.NumberFormat. Options
 *   must include {useGrouping: false}, and must cause 1.1 to be formatted
 *   pre- and post-decimal digits.
 * @param {Object} testData maps input data (in ES5 9.3.1 format) to expected output strings
 *   in unlocalized format with Western digits.
 */

function testNumberFormat(locales, numberingSystems, options, testData) {
  locales.forEach(function (locale) {
    numberingSystems.forEach(function (numbering) {
      var digits = numberingSystemDigits[numbering];
      var format = new Intl.NumberFormat([locale + "-u-nu-" + numbering], options);

      function getPatternParts(positive) {
        var n = positive ? 1.1 : -1.1;
        var formatted = format.format(n);
        var oneoneRE = "([^" + digits + "]*)[" + digits + "]+([^" + digits + "]+)[" + digits + "]+([^" + digits + "]*)";
        var match = formatted.match(new RegExp(oneoneRE));
        if (match === null) {
          $ERROR("Unexpected formatted " + n + " for " +
            format.resolvedOptions().locale + " and options " +
            JSON.stringify(options) + ": " + formatted);
        }
        return match;
      }

      function toNumbering(raw) {
        return raw.replace(/[0-9]/g, function (digit) {
          return digits[digit.charCodeAt(0) - "0".charCodeAt(0)];
        });
      }

      function buildExpected(raw, patternParts) {
        var period = raw.indexOf(".");
        if (period === -1) {
          return patternParts[1] + toNumbering(raw) + patternParts[3];
        } else {
          return patternParts[1] +
            toNumbering(raw.substring(0, period)) +
            patternParts[2] +
            toNumbering(raw.substring(period + 1)) +
            patternParts[3];
        }
      }

      if (format.resolvedOptions().numberingSystem === numbering) {
        // figure out prefixes, infixes, suffixes for positive and negative values
        var posPatternParts = getPatternParts(true);
        var negPatternParts = getPatternParts(false);

        Object.getOwnPropertyNames(testData).forEach(function (input) {
          var rawExpected = testData[input];
          var patternParts;
          if (rawExpected[0] === "-") {
            patternParts = negPatternParts;
            rawExpected = rawExpected.substring(1);
          } else {
            patternParts = posPatternParts;
          }
          var expected = buildExpected(rawExpected, patternParts);
          var actual = format.format(input);
          if (actual !== expected) {
            $ERROR("Formatted value for " + input + ", " +
            format.resolvedOptions().locale + " and options " +
            JSON.stringify(options) + " is " + actual + "; expected " + expected + ".");
          }
        });
      }
    });
  });
}


/**
 * Return the components of date-time formats.
 * @return {Array} an array with all date-time components.
 */

function getDateTimeComponents() {
  return ["weekday", "era", "year", "month", "day", "hour", "minute", "second", "timeZoneName"];
}


/**
 * Return the valid values for the given date-time component, as specified
 * by the table in section 12.1.1.
 * @param {string} component a date-time component.
 * @return {Array} an array with the valid values for the component.
 */

function getDateTimeComponentValues(component) {

  var components = {
    weekday: ["narrow", "short", "long"],
    era: ["narrow", "short", "long"],
    year: ["2-digit", "numeric"],
    month: ["2-digit", "numeric", "narrow", "short", "long"],
    day: ["2-digit", "numeric"],
    hour: ["2-digit", "numeric"],
    minute: ["2-digit", "numeric"],
    second: ["2-digit", "numeric"],
    timeZoneName: ["short", "long"]
  };

  var result = components[component];
  if (result === undefined) {
    $ERROR("Internal error: No values defined for date-time component " + component + ".");
  }
  return result;
}


/**
 * @description Tests whether timeZone is a String value representing a
 * structurally valid and canonicalized time zone name, as defined in
 * sections 6.4.1 and 6.4.2 of the ECMAScript Internationalization API
 * Specification.
 * @param {String} timeZone the string to be tested.
 * @result {Boolean} whether the test succeeded.
 */

function isCanonicalizedStructurallyValidTimeZoneName(timeZone) {
  /**
   * Regular expression defining IANA Time Zone names.
   *
   * Spec: IANA Time Zone Database, Theory file
   */
  var fileNameComponent = "(?:[A-Za-z_]|\\.(?!\\.?(?:/|$)))[A-Za-z.\\-_]{0,13}";
  var fileName = fileNameComponent + "(?:/" + fileNameComponent + ")*";
  var etcName = "(?:Etc/)?GMT[+-]\\d{1,2}";
  var systemVName = "SystemV/[A-Z]{3}\\d{1,2}(?:[A-Z]{3})?";
  var legacyName = etcName + "|" + systemVName + "|CST6CDT|EST5EDT|MST7MDT|PST8PDT|NZ";
  var zoneNamePattern = new RegExp("^(?:" + fileName + "|" + legacyName + ")$");

  if (typeof timeZone !== "string") {
    return false;
  }
  // 6.4.2 CanonicalizeTimeZoneName (timeZone), step 3
  if (timeZone === "UTC") {
    return true;
  }
  // 6.4.2 CanonicalizeTimeZoneName (timeZone), step 3
  if (timeZone === "Etc/UTC" || timeZone === "Etc/GMT") {
    return false;
  }
  return zoneNamePattern.test(timeZone);
}
