Correctly disallow calendared monthday/yearmonth strings whilst still allowing calendared datetime strings (#3133)

* Correctly disallow calendared monthday/yearmonth strings whilst still allowing calendared datetime strings

* Update spec/abstractops.html

Co-authored-by: Shane F. Carr <[email protected]>

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Co-authored-by: Shane F. Carr <[email protected]>

Author: Manishearth

spec/abstractops.html

@@ -1503,8 +1503,11 @@ <h1>
                   1. If _annotation_ contains an |AnnotationCriticalFlag| Parse Node, or _calendarWasCritical_ is *true*, throw a *RangeError* exception.
               1. Else,
                 1. If _annotation_ contains an |AnnotationCriticalFlag| Parse Node, throw a *RangeError* exception.
-            1. If _goal_ is |TemporalMonthDayString| or |TemporalYearMonthString|, _calendar_ is not ~empty~, and the ASCII-lowercase of _calendar_ is not *"iso8601"*, throw a *RangeError* exception.
-            1. If _goal_ is |TemporalMonthDayString| and _parseResult_ does not contain a |DateYear| Parse Node, set _yearAbsent_ to *true*.
+            1. If _goal_ is |TemporalYearMonthString| and _parseResult_ does not contain a |DateDay| Parse Node, then
+              1. If _calendar_ is not ~empty~ and the ASCII-lowercase of _calendar_ is not *"iso8601"*, throw a *RangeError* exception.
+            1. If _goal_ is |TemporalMonthDayString| and _parseResult_ does not contain a |DateYear| Parse Node, then
+              1. If _calendar_ is not ~empty~ and the ASCII-lowercase of _calendar_ is not *"iso8601"*, throw a *RangeError* exception.
+              1. Set _yearAbsent_ to *true*.
       1. If _parseResult_ is not a Parse Node, throw a *RangeError* exception.
       1. NOTE: Applications of StringToNumber below do not lose precision, since each of the parsed values is guaranteed to be a sufficiently short string of decimal digits.
       1. Let each of _year_, _month_, _day_, _hour_, _minute_, _second_, and _fSeconds_ be the source text matched by the respective |DateYear|, |DateMonth|, |DateDay|, the first |Hour|, the first |MinuteSecond|, |TimeSecond|, and the first |TemporalDecimalFraction| Parse Node contained within _parseResult_, or an empty sequence of code points if not present.