Ship Intl.DateTimeFormat.formatToParts()

test/intl/date-format/date-format-to-parts.js

 // Copyright 2016 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// Flags: --datetime-format-to-parts
-

[Dan Ehrenberg, 2016/12/16 23:40:08]

Could you leave the Flags: line in until the later patch to remove the flag
altogether? This would make a potential revert more minimal.

[jungshik at Google, 2016/12/19 07:27:43]

Done.

 var d = new Date(2016, 11, 15, 14, 10, 34);
 var df = Intl.DateTimeFormat("ja",
     {hour: 'numeric', minute: 'numeric', second: 'numeric', year: 'numeric',
      month: 'numeric', day: 'numeric', timeZoneName: 'short', era: 'short'});
 
 var formattedParts = df.formatToParts(d);
 
 var formattedReconstructedFromParts = formattedParts.map((part) => part.value)
     .reduce((accumulated, part) => accumulated + part);
 assertEquals(df.format(d), formattedReconstructedFromParts);
 // 西暦2016年11月15日 14:10:34 GMT-7
 assertEquals(["era", "year", "literal", "month", "literal", "day", "literal",
               "hour", "literal", "minute", "literal", "second", "literal",
               "timeZoneName"], formattedParts.map((part) => part.type));