Polyfill fix to format plain Temporal objects in UTC #3257
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without regard to DST. This implements normative change of PR tc39#3246 in the polyfill.
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…ones. These are basic tests for proposal-temporal's normative change PR tc39/proposal-temporal#3246 and polyfill fix PR tc39/proposal-temporal#3257 More tests will be added here to include tests of .toLocaleString for PlainTime, PlainDate, PlainYearMonth, PlainMonthDay, and tests for formatToParts, formatRange, and formatRangeToParts.
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Some basic tests are in this test262 draft PR: tc39/test262#4878 |
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…ones. These are tests for proposal-temporal's normative change PR tc39/proposal-temporal#3246 and polyfill fix PR tc39/proposal-temporal#3257
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| function getSlotLazy(obj, slot, isPlain) { | ||
| let val = GetSlot(obj, slot); | ||
| if (typeof val === 'function') { | ||
| val = new IntlDateTimeFormat(GetSlot(obj, LOCALE), val(GetSlot(obj, OPTIONS))); | ||
| const baseOptions = val(GetSlot(obj, OPTIONS)); | ||
| const options = ObjectAssign({}, baseOptions); | ||
| const amendedOptions = val(options); | ||
| if (isPlain) { | ||
| amendedOptions.timeZone = 'UTC'; | ||
| } | ||
| val = new IntlDateTimeFormat(GetSlot(obj, LOCALE), amendedOptions); |
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This works, but can be optimized further: I think we can set options.timeZone = 'UTC' in each of the amend functions, rather than here, because when we read e.g. the DATE slot, it will always be with isPlain = true.
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…ones. These are tests for proposal-temporal's normative change PR tc39/proposal-temporal#3246 and polyfill fix PR tc39/proposal-temporal#3257
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Rebased, pushed a commit to address my own comment, and merged into #3246. Thanks! |
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without regard to DST.
This implements normative change of PR #3246 in the polyfill.
Related to issue #3212
This adds a new (boolean) argument
isPlaintogetSlotLazy, which, whenisPlainis set totruecopies the options object of the cachedIntl.DateTimeFormatobject and amends the copied options to havetimeZone = 'UTC'.Then from
extractOverrideswe useGetUTCEpochNanosecondsto calculate the nanoseconds of the plain temporal objects, and get a formatter for these usinggetSlotLazywith theisPlainargument set totrue. Thus the formatter for the plain objects can be aware that the nanoseconds calculated for these objects are UTC based, independent of the actual timezone it was created in.This makes the plain* objects be UTC based, implementing the changes in #3246 as closely as possible.