Revert "Editorial: Move AnnotatedTime early error to a separate parse step"

This reverts commit fa3d0b9.
It introduced a regression; see discussion in
#3237.

Closes: #3237

Author: ptomato

polyfill/test/validStrings.mjs

@@ -315,7 +315,18 @@ const dateTime = (z, timeRequired) =>
   );
 const annotatedTime = choice(
   seq(timeDesignator, time, [dateTimeUTCOffset(false)], [timeZoneAnnotation], [annotations]),
-  seq(time, [dateTimeUTCOffset(false)], [timeZoneAnnotation], [annotations])
+  seq(
+    withSyntaxConstraints(seq(time, [dateTimeUTCOffset(false)]), (result) => {
+      if (/^(?:(?!02-?30)(?:0[1-9]|1[012])-?(?:0[1-9]|[12][0-9]|30)|(?:0[13578]|10|12)-?31)$/.test(result)) {
+        throw new SyntaxError('valid PlainMonthDay');
+      }
+      if (/^(?!-000000)(?:[0-9]{4}|[+-][0-9]{6})-?(?:0[1-9]|1[012])$/.test(result)) {
+        throw new SyntaxError('valid PlainYearMonth');
+      }
+    }),
+    [timeZoneAnnotation],
+    [annotations]
+  )
 );
 const annotatedDateTime = (zoned, timeRequired) =>
   seq(dateTime(zoned, timeRequired), zoned ? timeZoneAnnotation : [timeZoneAnnotation], [annotations]);
@@ -451,20 +462,7 @@ const goals = {
   DateTime: annotatedDateTime(false, false),
   Duration: duration,
   MonthDay: choice(annotatedMonthDay, annotatedDateTime(false, false)),
-  Time: withSyntaxConstraints(choice(annotatedTime, annotatedDateTime(false, true)), (result) => {
-    try {
-      ES.ParseTemporalMonthDayString(result);
-      throw new SyntaxError('valid PlainMonthDay');
-    } catch (e) {
-      if (e instanceof SyntaxError) throw e;
-    }
-    try {
-      ES.ParseTemporalYearMonthString(result);
-      throw new SyntaxError('valid PlainYearMonth');
-    } catch (e) {
-      if (e instanceof SyntaxError) throw e;
-    }
-  }),
+  Time: choice(annotatedTime, annotatedDateTime(false, true)),
   TimeZone: choice(timeZoneIdentifier, zonedDateTime, instant),
   YearMonth: choice(annotatedYearMonth, annotatedDateTime(false, false)),
   ZonedDateTime: zonedDateTime

spec/abstractops.html

@@ -1230,7 +1230,9 @@ <h1>RFC 9557 / ISO 8601 grammar</h1>
       AnnotatedTime :::
         TimeDesignator Time DateTimeUTCOffset[~Z]? TimeZoneAnnotation? Annotations?
         Time DateTimeUTCOffset[~Z]? TimeZoneAnnotation? Annotations?
-
+    </emu-grammar>
+    <p>Note the disambiguation between the second alternative without |TimeDesignator|, and |DateSpecMonthDay|/|DateSpecYearMonth| in <emu-xref href="#sec-temporal-iso8601grammar-static-semantics-early-errors"></emu-xref>.</p>
+    <emu-grammar type="definition">
       AnnotatedDateTime[Zoned, TimeRequired] :::
         [~Zoned] DateTime[~Z, ?TimeRequired] TimeZoneAnnotation? Annotations?
         [+Zoned] DateTime[+Z, ?TimeRequired] TimeZoneAnnotation Annotations?
@@ -1300,10 +1302,6 @@ <h1>RFC 9557 / ISO 8601 grammar</h1>
         AnnotatedTime
         AnnotatedDateTime[~Zoned, +TimeRequired]
 
-      AmbiguousTemporalTimeString :::
-        DateSpecMonthDay TimeZoneAnnotation? Annotations?
-        DateSpecYearMonth TimeZoneAnnotation? Annotations?
-
       TemporalYearMonthString :::
         AnnotatedYearMonth
         AnnotatedDateTime[~Zoned, ~TimeRequired]
@@ -1344,6 +1342,18 @@ <h1>Static Semantics: IsValidDate ( ): a Boolean</h1>
 
     <emu-clause id="sec-temporal-iso8601grammar-static-semantics-early-errors">
       <h1>Static Semantics: Early Errors</h1>
+      <emu-grammar>
+        AnnotatedTime :::
+          Time DateTimeUTCOffset[~Z]? TimeZoneAnnotation? Annotations?
+      </emu-grammar>
+      <ul>
+        <li>
+          It is a Syntax Error if ParseText(|Time| |DateTimeUTCOffset[~Z]|, |DateSpecMonthDay|) is a Parse Node.
+        </li>
+        <li>
+          It is a Syntax Error if ParseText(|Time| |DateTimeUTCOffset[~Z]|, |DateSpecYearMonth|) is a Parse Node.
+        </li>
+      </ul>
       <emu-grammar>
         DateSpec[Extended] :::
           DateYear DateSeparator[?Extended] DateMonth DateSeparator[?Extended] DateDay

spec/plaintime.html

@@ -573,9 +573,9 @@ <h1>
         1. Else,
           1. If _item_ is not a String, throw a *TypeError* exception.
           1. Let _parseResult_ be ? ParseISODateTime(_item_, « |TemporalTimeString| »).
-          1. If ParseText(StringToCodePoints(_item_), |AmbiguousTemporalTimeString|) is a Parse Node, throw a *RangeError* exception.
           1. Assert: _parseResult_.[[Time]] is not ~start-of-day~.
           1. Set _result_ to _parseResult_.[[Time]].
+          1. NOTE: A successful parse using |TemporalTimeString| guarantees absence of ambiguity with respect to any ISO 8601 date-only, year-month, or month-day representation.
           1. Let _resolvedOptions_ be ? GetOptionsObject(_options_).
           1. Perform ? GetTemporalOverflowOption(_resolvedOptions_).
         1. Return ! CreateTemporalTime(_result_).