text: // Copyright (C) 2021 André Bargull. All rights reserved.
  // This code is governed by the BSD license found in the LICENSE file.
  
  /*---
  esid: sec-intl.supportedvaluesof
  description: >
    The returned "currency" values are sorted, unique, and upper-case canonicalised.
  info: |
    Intl.supportedValuesOf ( key )
  
    1. Let key be ? ToString(key).
    ...
    4. Else if key is "currency", then
      a. Let list be ! AvailableCurrencies( ).
    ...
    9. Return ! CreateArrayFromList( list ).
  
    AvailableCurrencies ( )
      The AvailableCurrencies abstract operation returns a List, ordered as if an
      Array of the same values had been sorted using %Array.prototype.sort% using
      undefined as comparefn, that contains unique, well-formed, and upper case
      canonicalized 3-letter ISO 4217 currency codes, identifying the currencies
      for which the implementation provides the functionality of Intl.DisplayNames
      and Intl.NumberFormat objects.
  includes: [compareArray.js]
  features: [Intl-enumeration]
  ---*/
  
  const currencies = Intl.supportedValuesOf("currency");
  
  assert(Array.isArray(currencies), "Returns an Array object.");
  assert.sameValue(Object.getPrototypeOf(currencies), Array.prototype,
                   "The array prototype is Array.prototype");
  
  const otherCurrencies = Intl.supportedValuesOf("currency");
  assert.notSameValue(otherCurrencies, currencies,
                      "Returns a new array object for each call.");
  
  assert.compareArray(currencies, otherCurrencies.sort(),
                      "The array is sorted.");
  
  assert.sameValue(new Set(currencies).size, currencies.length,
                   "The array doesn't contain duplicates.");
  
  const codeRE = /^[A-Z]{3}$/;
  for (let currency of currencies) {
    assert(codeRE.test(currency), `${currency} is a 3-letter ISO 4217 currency code`);
  }
  