Copy objects received from user code before passing them into user co…

…de again

The intention of this is that any getters installed on an object received
from user code are called once each, in a defined order.

Requires a few fixes to make the polyfill match the spec text.

See: #1426

polyfill/lib/ecmascript.mjs

@@ -1123,10 +1123,10 @@ export const ES = ObjectAssign({}, ES2020, {
       ['month', undefined],
       ['monthCode', undefined],
       ['nanosecond', 0],
-      ['offset', undefined],
       ['second', 0],
-      ['timeZone'],
-      ['year', undefined]
+      ['year', undefined],
+      ['offset', undefined],
+      ['timeZone']
     ];
     // Add extra fields from the calendar at the end
     fieldNames.forEach((fieldName) => {

polyfill/lib/plaindate.mjs

@@ -141,6 +141,7 @@ export class PlainDate {
     }
     let fields = ES.ToTemporalDateFields(this, fieldNames);
     fields = ES.CalendarMergeFields(calendar, fields, props);
+    fields = ES.ToTemporalDateFields(fields, fieldNames);
 
     options = ES.NormalizeOptionsObject(options);
 

polyfill/lib/plaindatetime.mjs

@@ -232,6 +232,7 @@ export class PlainDateTime {
     }
     let fields = ES.ToTemporalDateTimeFields(this, fieldNames);
     fields = ES.CalendarMergeFields(calendar, fields, props);
+    fields = ES.ToTemporalDateTimeFields(fields, fieldNames);
     const {
       year,
       month,

polyfill/lib/plainmonthday.mjs

@@ -88,6 +88,7 @@ export class PlainMonthDay {
     }
     let fields = ES.ToTemporalMonthDayFields(this, fieldNames);
     fields = ES.CalendarMergeFields(calendar, fields, props);
+    fields = ES.ToTemporalMonthDayFields(fields, fieldNames);
 
     options = ES.NormalizeOptionsObject(options);
     return ES.MonthDayFromFields(calendar, fields, options);
@@ -124,18 +125,28 @@ export class PlainMonthDay {
     const calendar = GetSlot(this, CALENDAR);
 
     const receiverFieldNames = ES.CalendarFields(calendar, ['day', 'monthCode']);
-    const fields = ES.ToTemporalMonthDayFields(this, receiverFieldNames);
+    let fields = ES.ToTemporalMonthDayFields(this, receiverFieldNames);
 
     const inputFieldNames = ES.CalendarFields(calendar, ['year']);
-    const entries = [['year']];
+    const inputEntries = [['year']];
     // Add extra fields from the calendar at the end
     inputFieldNames.forEach((fieldName) => {
-      if (!entries.some(([name]) => name === fieldName)) {
-        entries.push([fieldName, undefined]);
+      if (!inputEntries.some(([name]) => name === fieldName)) {
+        inputEntries.push([fieldName, undefined]);
       }
     });
-    ObjectAssign(fields, ES.PrepareTemporalFields(item, entries));
-    return ES.DateFromFields(calendar, fields);
+    const inputFields = ES.PrepareTemporalFields(item, inputEntries);
+    let mergedFields = ES.CalendarMergeFields(calendar, fields, inputFields);
+
+    const mergedFieldNames = [...new Set([...receiverFieldNames, ...inputFieldNames])];
+    const mergedEntries = [];
+    mergedFieldNames.forEach((fieldName) => {
+      if (!mergedEntries.some(([name]) => name === fieldName)) {
+        mergedEntries.push([fieldName, undefined]);
+      }
+    });
+    mergedFields = ES.PrepareTemporalFields(mergedFields, mergedEntries);
+    return ES.DateFromFields(calendar, mergedFields);
   }
   getISOFields() {
     if (!ES.IsTemporalMonthDay(this)) throw new TypeError('invalid receiver');

polyfill/lib/plainyearmonth.mjs

@@ -113,6 +113,7 @@ export class PlainYearMonth {
     }
     let fields = ES.ToTemporalYearMonthFields(this, fieldNames);
     fields = ES.CalendarMergeFields(calendar, fields, props);
+    fields = ES.ToTemporalYearMonthFields(fields, fieldNames);
 
     options = ES.NormalizeOptionsObject(options);
 
@@ -348,18 +349,28 @@ export class PlainYearMonth {
     const calendar = GetSlot(this, CALENDAR);
 
     const receiverFieldNames = ES.CalendarFields(calendar, ['monthCode', 'year']);
-    const fields = ES.ToTemporalYearMonthFields(this, receiverFieldNames);
+    let fields = ES.ToTemporalYearMonthFields(this, receiverFieldNames);
 
     const inputFieldNames = ES.CalendarFields(calendar, ['day']);
-    const entries = [['day']];
+    const inputEntries = [['day']];
     // Add extra fields from the calendar at the end
     inputFieldNames.forEach((fieldName) => {
-      if (!entries.some(([name]) => name === fieldName)) {
-        entries.push([fieldName, undefined]);
+      if (!inputEntries.some(([name]) => name === fieldName)) {
+        inputEntries.push([fieldName, undefined]);
       }
     });
-    ObjectAssign(fields, ES.PrepareTemporalFields(item, entries));
-    return ES.DateFromFields(calendar, fields, { overflow: 'reject' });
+    const inputFields = ES.PrepareTemporalFields(item, inputEntries);
+    let mergedFields = ES.CalendarMergeFields(calendar, fields, inputFields);
+
+    const mergedFieldNames = [...new Set([...receiverFieldNames, ...inputFieldNames])];
+    const mergedEntries = [];
+    mergedFieldNames.forEach((fieldName) => {
+      if (!mergedEntries.some(([name]) => name === fieldName)) {
+        mergedEntries.push([fieldName, undefined]);
+      }
+    });
+    mergedFields = ES.PrepareTemporalFields(mergedFields, mergedEntries);
+    return ES.DateFromFields(calendar, mergedFields, { overflow: 'reject' });
   }
   getISOFields() {
     if (!ES.IsTemporalYearMonth(this)) throw new TypeError('invalid receiver');

polyfill/lib/zoneddatetime.mjs

@@ -226,6 +226,7 @@ export class ZonedDateTime {
     }
     let fields = ES.ToTemporalZonedDateTimeFields(this, fieldNames);
     fields = ES.CalendarMergeFields(calendar, fields, props);
+    fields = ES.ToTemporalZonedDateTimeFields(fields, fieldNames);
     let {
       year,
       month,

spec/plaindate.html

@@ -386,6 +386,7 @@ <h1>Temporal.PlainDate.prototype.with ( _temporalDateLike_ [ , _options_ ] )</h1
         1. Set _options_ to ? NormalizeOptionsObject(_options_).
         1. Let _fields_ be ? PrepareTemporalFields(_temporalDate_, _fieldNames_, «»).
         1. Set _fields_ to ? CalendarMergeFields(_calendar_, _fields_, _partialDate_).
+        1. Set _fields_ to ? PrepareTemporalFields(_fields_, _fieldNames_, «»).
         1. Return ? DateFromFields(_calendar_, _fields_, _options_).
       </emu-alg>
     </emu-clause>

spec/plaindatetime.html

@@ -388,6 +388,7 @@ <h1>Temporal.PlainDateTime.prototype.with ( _temporalDateTimeLike_ [ , _options_
         1. Set _options_ to ? NormalizeOptionsObject(_options_).
         1. Let _fields_ be ? PrepareTemporalFields(_dateTime_, _fieldNames_, «»).
         1. Set _fields_ to ? CalendarMergeFields(_calendar_, _fields_, _partialDateTime_).
+        1. Set _fields_ to ? PrepareTemporalFields(_fields_, _fieldNames_, «»).
         1. Let _result_ be ? InterpretTemporalDateTimeFields(_calendar_, _fields_, _options_).
         1. Assert: ! ValidateISODateTime(_result_.[[Year]], _result_.[[Month]], _result_.[[Day]], _result_.[[Hour]], _result_.[[Minute]], _result_.[[Second]], _result_.[[Millisecond]], _result_.[[Microsecond]], _result_.[[Nanosecond]]) is *true*.
         1. Return ? CreateTemporalDateTime(_result_.[[Year]], _result_.[[Month]], _result_.[[Day]], _result_.[[Hour]], _result_.[[Minute]], _result_.[[Second]], _result_.[[Millisecond]], _result_.[[Microsecond]], _result_.[[Nanosecond]], _calendar_).

spec/plainmonthday.html

@@ -152,6 +152,7 @@ <h1>Temporal.PlainMonthDay.prototype.with ( _temporalMonthDayLike_ [ , _options_
         1. Set _options_ to ? NormalizeOptionsObject(_options_).
         1. Let _fields_ be ? PrepareTemporalFields(_monthDay_, _fieldNames_, «»).
         1. Set _fields_ to ? CalendarMergeFields(_calendar_, _fields_, _partialMonthDay_).
+        1. Set _fields_ to ? PrepareTemporalFields(_fields_, _fieldNames_, «»).
         1. Return ? MonthDayFromFields(_calendar_, _fields_, _options_).
       </emu-alg>
     </emu-clause>
@@ -243,6 +244,8 @@ <h1>Temporal.PlainMonthDay.prototype.toPlainDate ( _item_ )</h1>
         1. Let _inputFieldNames_ be ? CalendarFields(_calendar_, « *"year"* »).
         1. Let _inputFields_ be ? PrepareTemporalFields(_item_, _inputFieldNames_, «»).
         1. Let _mergedFields_ be ? CalendarMergeFields(_calendar_, _fields_, _inputFields_).
+        1. Let _mergedFieldNames_ be the List containing all the elements of _receiverFieldNames_ followed by all the elements of _inputFieldNames_, with duplicate elements removed.
+        1. Set _mergedFields_ to ? PrepareTemporalFields(_mergedFields_, _mergedFieldNames_, «»).
         1. Let _options_ be ! OrdinaryObjectCreate(%Object.prototype%).
         1. Perform ! CreateDataPropertyOrThrow(_options_, *"overflow"*, *"reject"*).
         1. Return ? DateFromFields(_calendar_, _mergedFields_, _options_).

spec/plainyearmonth.html

@@ -234,6 +234,7 @@ <h1>Temporal.PlainYearMonth.prototype.with ( _temporalYearMonthLike_ [ , _option
         1. Set _options_ to ? NormalizeOptionsObject(_options_).
         1. Let _fields_ be ? PrepareTemporalFields(_yearMonth_, _fieldNames_, «»).
         1. Set _fields_ to ? CalendarMergeFields(_calendar_, _fields_, _partialYearMonth_).
+        1. Set _fields_ to ? PrepareTemporalFields(_fields_, _fieldNames_, «»).
         1. Return ? YearMonthFromFields(_calendar_, _fields_, _options_).
       </emu-alg>
     </emu-clause>
@@ -455,6 +456,8 @@ <h1>Temporal.PlainYearMonth.prototype.toPlainDate ( _item_ )</h1>
         1. Let _inputFieldNames_ be ? CalendarFields(_calendar_, « *"day"* »).
         1. Let _inputFields_ be ? PrepareTemporalFields(_item_, _inputFieldNames_, «»).
         1. Let _mergedFields_ be ? CalendarMergeFields(_calendar_, _fields_, _inputFields_).
+        1. Let _mergedFieldNames_ be the List containing all the elements of _receiverFieldNames_ followed by all the elements of _inputFieldNames_, with duplicate elements removed.
+        1. Set _mergedFields_ to ? PrepareTemporalFields(_mergedFields_, _mergedFieldNames_, «»).
         1. Let _options_ be ! OrdinaryObjectCreate(%Object.prototype%).
         1. Perform ! CreateDataPropertyOrThrow(_options_, *"overflow"*, *"reject"*).
         1. Return ? DateFromFields(_calendar_, _mergedFields_, _options_).

spec/zoneddatetime.html

@@ -575,6 +575,7 @@ <h1>Temporal.ZonedDateTime.prototype.with ( _temporalZonedDateTimeLike_ [ , _opt
         1. Append *"timeZone"* to _fieldNames_.
         1. Let _fields_ be ? PrepareTemporalFields(_zonedDateTime_, _fieldNames_, « *"timeZone"* »).
         1. Set _fields_ to ? CalendarMergeFields(_calendar_, _fields_, _partialZonedDateTime_).
+        1. Set _fields_ to ? PrepareTemporalFields(_fields_, _fieldNames_, « *"timeZone"* »).
         1. Let _offsetString_ be ? Get(_partialZonedDateTime_, *"offset"*).
         1. If _offsetString_ is not *undefined*, then
           1. Perform ? Set(_fields_, *"offset"*, _offsetString_).