Editorial: Simplify ToTemporalTimeRecord

ToTemporalTimeRecord can be simplified quite a lot and doesn't need to
call the more complicated PrepareTemporalFields. This change is
unobservable, but it's preparation for refactoring PrepareTemporalFields
in #2925.

polyfill/lib/ecmascript.mjs

@@ -23,7 +23,6 @@ const NumberMaxSafeInteger = Number.MAX_SAFE_INTEGER;
 const ObjectCreate = Object.create;
 const ObjectDefineProperty = Object.defineProperty;
 const ObjectEntries = Object.entries;
-const ObjectGetOwnPropertyDescriptor = Object.getOwnPropertyDescriptor;
 const SetPrototypeHas = Set.prototype.has;
 const StringCtor = String;
 const StringFromCharCode = String.fromCharCode;
@@ -1136,8 +1135,7 @@ export function PrepareTemporalFields(
   fields,
   requiredFields,
   extraFieldDescriptors = [],
-  duplicateBehaviour = 'throw',
-  { emptySourceErrorMessage = 'no supported properties found' } = {}
+  duplicateBehaviour = 'throw'
 ) {
   const result = ObjectCreate(null);
   let any = false;
@@ -1186,7 +1184,7 @@ export function PrepareTemporalFields(
     previousProperty = property;
   }
   if (requiredFields === 'partial' && !any) {
-    throw new TypeError(emptySourceErrorMessage);
+    throw new TypeError('no supported properties found');
   }
   return result;
 }
@@ -1232,19 +1230,19 @@ export function PrepareCalendarFields(calendarRec, bag, calendarFieldNames, nonC
 
 export function ToTemporalTimeRecord(bag, completeness = 'complete') {
   const fields = ['hour', 'microsecond', 'millisecond', 'minute', 'nanosecond', 'second'];
-  const partial = PrepareTemporalFields(bag, fields, 'partial', undefined, undefined, {
-    emptySourceErrorMessage: 'invalid time-like'
-  });
-  const result = {};
+  let any = false;
+  const result = ObjectCreate(null);
   for (let index = 0; index < fields.length; index++) {
     const field = fields[index];
-    const valueDesc = ObjectGetOwnPropertyDescriptor(partial, field);
-    if (valueDesc !== undefined) {
-      result[field] = valueDesc.value;
+    const value = bag[field];
+    if (value !== undefined) {
+      result[field] = ToIntegerWithTruncation(value);
+      any = true;
     } else if (completeness === 'complete') {
       result[field] = 0;
     }
   }
+  if (!any) throw new TypeError('invalid time-like');
   return result;
 }
 

spec/plaintime.html

@@ -816,35 +816,36 @@ <h1>
       </dl>
       <emu-alg>
         1. If _completeness_ is not present, set _completeness_ to ~complete~.
-        1. Let _partial_ be ? PrepareTemporalFields(_temporalTimeLike_, « *"hour"*, *"microsecond"*, *"millisecond"*, *"minute"*, *"nanosecond"*, *"second"* », ~partial~).
         1. If _completeness_ is ~complete~, then
           1. Let _result_ be a new TemporalTimeLike Record with each field set to 0.
         1. Else,
-          1. Let _result_ be a new TemporalTimeLike Record with each field set to *undefined*.
-        1. Let _hourDesc_ be OrdinaryGetOwnProperty(_partial_, *"hour"*).
-        1. If _hourDesc_ is not *undefined*, then
-          1. Assert: _hourDesc_ is a data Property Descriptor.
-          1. Set _result_.[[Hour]] to ℝ(_hourDesc_.[[Value]]).
-        1. Let _minuteDesc_ be OrdinaryGetOwnProperty(_partial_, *"minute"*).
-        1. If _minuteDesc_ is not *undefined*, then
-          1. Assert: _minuteDesc_ is a data Property Descriptor.
-          1. Set _result_.[[Minute]] to ℝ(_minuteDesc_.[[Value]]).
-        1. Let _secondDesc_ be OrdinaryGetOwnProperty(_partial_, *"second"*).
-        1. If _secondDesc_ is not *undefined*, then
-          1. Assert: _secondDesc_ is a data Property Descriptor.
-          1. Set _result_.[[Second]] to ℝ(_secondDesc_.[[Value]]).
-        1. Let _millisecondDesc_ be OrdinaryGetOwnProperty(_partial_, *"millisecond"*).
-        1. If _millisecondDesc_ is not *undefined*, then
-          1. Assert: _millisecondDesc_ is a data Property Descriptor.
-          1. Set _result_.[[Millisecond]] to ℝ(_millisecondDesc_.[[Value]]).
-        1. Let _microsecondDesc_ be OrdinaryGetOwnProperty(_partial_, *"microsecond"*).
-        1. If _microsecondDesc_ is not *undefined*, then
-          1. Assert: _microsecondDesc_ is a data Property Descriptor.
-          1. Set _result_.[[Microsecond]] to ℝ(_microsecondDesc_.[[Value]]).
-        1. Let _nanosecondDesc_ be OrdinaryGetOwnProperty(_partial_, *"nanosecond"*).
-        1. If _nanosecondDesc_ is not *undefined*, then
-          1. Assert: _nanosecondDesc_ is a data Property Descriptor.
-          1. Set _result_.[[Nanosecond]] to ℝ(_nanosecondDesc_.[[Value]]).
+          1. Let _result_ be a new TemporalTimeLike Record with each field set to ~unset~.
+        1. Let _any_ be *false*.
+        1. Let _hour_ be ? Get(_temporalTimeLike_, *"hour"*).
+        1. If _hour_ is not *undefined*, then
+          1. Set _result_.[[Hour]] to ? ToIntegerWithTruncation(_hour_).
+          1. Set _any_ to *true*.
+        1. Let _microsecond_ be ? Get(_temporalTimeLike_, *"microsecond"*).
+        1. If _microsecond_ is not *undefined*, then
+          1. Set _result_.[[Microsecond]] to ? ToIntegerWithTruncation(_microsecond_).
+          1. Set _any_ to *true*.
+        1. Let _millisecond_ be ? Get(_temporalTimeLike_, *"millisecond"*).
+        1. If _millisecond_ is not *undefined*, then
+          1. Set _result_.[[Millisecond]] to ? ToIntegerWithTruncation(_millisecond_).
+          1. Set _any_ to *true*.
+        1. Let _minute_ be ? Get(_temporalTimeLike_, *"minute"*).
+        1. If _minute_ is not *undefined*, then
+          1. Set _result_.[[Minute]] to ? ToIntegerWithTruncation(_minute_).
+          1. Set _any_ to *true*.
+        1. Let _nanosecond_ be ? Get(_temporalTimeLike_, *"nanosecond"*).
+        1. If _nanosecond_ is not *undefined*, then
+          1. Set _result_.[[Nanosecond]] to ? ToIntegerWithTruncation(_nanosecond_).
+          1. Set _any_ to *true*.
+        1. Let _second_ be ? Get(_temporalTimeLike_, *"second"*).
+        1. If _second_ is not *undefined*, then
+          1. Set _result_.[[Second]] to ? ToIntegerWithTruncation(_second_).
+          1. Set _any_ to *true*.
+        1. If _any_ is *false*, throw a *TypeError* exception.
         1. Return _result_.
       </emu-alg>