JSTests/test262/test/intl402/DisplayNames/prototype/resolvedOptions/option-fallback.js

// Copyright (C) 2019 Leo Balter. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.

/*---
esid: sec-Intl.DisplayNames.prototype.resolvedOptions
description: >
  Values for the fallback option
info: |
  Intl.DisplayNames.prototype.resolvedOptions ()

  1. Let pr be the this value.
  2. If Type(pr) is not Object or pr does not have an [[InitializedDisplayNames]] internal slot,
    throw a TypeError exception.
  3. Let options be ! ObjectCreate(%ObjectPrototype%).
  4. For each row of Table 6, except the header row, in table order, do
    a. Let p be the Property value of the current row.
    b. Let v be the value of pr's internal slot whose name is the Internal Slot value of the current row.
    c. If v is not undefined, then
      i. Perform ! CreateDataPropertyOrThrow(options, p, v).
  6. Return options.

  Table 6: Resolved Options of DisplayNames Instances

  [[Locale]]: "locale"
  [[Style]]: "style"
  [[Type]]: "type"
  [[Fallback]]: "fallback"

  Intl.DisplayNames ([ locales [ , options ]])

  ...
  8. Let matcher be ? GetOption(options, "localeMatcher", "string", « "lookup", "best fit" », "best fit").
  ...
  10. Let r be ResolveLocale(%DisplayNames%.[[AvailableLocales]], requestedLocales, opt,
    %DisplayNames%.[[RelevantExtensionKeys]]).
  11. Let style be ? GetOption(options, "style", "string", « "narrow", "short", "long" », "long").
  ...
  13. Let type be ? GetOption(options, "type", "string", « "language", "region", "script", "currency",
    "weekday", "month", "quarter", "dayPeriod", "dateTimeField" », "language").
  ...
  15. Let fallback be ? GetOption(options, "fallback", "string", « "code", "none" », "code").
  ...
  17. Set displayNames.[[Locale]] to the value of r.[[Locale]].
  ...

  CreateDataProperty ( O, P, V )

  ...
  3. Let newDesc be the PropertyDescriptor { [[Value]]: V, [[Writable]]: true, [[Enumerable]]: true,
    [[Configurable]]: true }.
  ...
locale: [en-US]
features: [Intl.DisplayNames]
includes: [propertyHelper.js]
---*/

var fallbacks = ['code', 'none'];

fallbacks.forEach(fallback => {
  var dn = new Intl.DisplayNames('en-US', { fallback });
  var options = dn.resolvedOptions();

  verifyProperty(options, 'fallback', {
    value: fallback,
    writable: true,
    enumerable: true,
    configurable: true
  });
  
  verifyProperty(options, 'type', {
    value: 'language',
    writable: true,
    enumerable: true,
    configurable: true
  });
  
  verifyProperty(options, 'style', {
    value: 'long',
    writable: true,
    enumerable: true,
    configurable: true
  });
});