Missing definitions for NonISOMonthDayToISOReferenceDate, NonISOCalendarISOToDate, and NonISOResolveFields

[anba]

Overrides for the following abstract operations should be provided:

• NonISOMonthDayToISOReferenceDate
• NonISOCalendarISOToDate
• NonISOResolveFields

[ptomato]

We didn't think those needed any overrides with calendar-specific information, beyond what is specified in Temporal. Are you missing any calendar-specific information that should be provided in an override?

[anba]

For example exact steps for NonISOResolveFields would be nice. This call:

Temporal.PlainMonthDay.from({calendar: "chinese", monthCode: "M04", day: 1, month: 5})

currently throws a RangeError in SM, whereas V8 and the spec-polyfill throw a TypeError. There was a change in the editorially marked commit tc39/proposal-temporal@f2ec05b for this to recommend a TypeError. But because notes are not normative, other behaviour is possibly also allowed.

[sffc]

See tc39/proposal-temporal#3166, unicode-org/icu4x#7083

I think the Temporal specification requires an ordering between TypeError (for missing fields) and RangeError (for invalid year/month/day in the calendar). This is a requirement for the ISO calendar, and the prose of NonISOResolveFields suggests the same.

I agree that it would be more clear and helpful if Intl Era Month Code had an override for NonISOResolveFields that stated this behavior in specification logic rather than in prose.