Remove TimeZoneToString abstract operation

Also remove %Temporal.TimeZone.prototype.toString% intrinsic. Similarly to
the previous commit, these are not needed because toString() is a required
method of the TimeZone protocol, so there should always be a toString()
there to call.

See: #1294

polyfill/lib/ecmascript.mjs

@@ -1509,13 +1509,13 @@ export const ES = ObjectAssign({}, ES2020, {
     return ES.TimeZoneFrom(identifier);
   },
   TimeZoneCompare: (one, two) => {
-    const tz1 = ES.TimeZoneToString(one);
-    const tz2 = ES.TimeZoneToString(two);
+    const tz1 = ES.ToString(one);
+    const tz2 = ES.ToString(two);
     return tz1 < tz2 ? -1 : tz1 > tz2 ? 1 : 0;
   },
   TimeZoneEquals: (one, two) => {
-    const tz1 = ES.TimeZoneToString(one);
-    const tz2 = ES.TimeZoneToString(two);
+    const tz1 = ES.ToString(one);
+    const tz2 = ES.ToString(two);
     return tz1 === tz2;
   },
   TemporalDateTimeToDate: (dateTime) => {
@@ -1578,13 +1578,6 @@ export const ES = ObjectAssign({}, ES2020, {
     }
     return ES.Call(getInstantFor, timeZone, [dateTime, { disambiguation }]);
   },
-  TimeZoneToString: (timeZone) => {
-    let toString = timeZone.toString;
-    if (toString === undefined) {
-      toString = GetIntrinsic('%Temporal.TimeZone.prototype.toString%');
-    }
-    return ES.ToString(ES.Call(toString, timeZone));
-  },
   ISOYearString: (year) => {
     let yearString;
     if (year < 1000 || year > 9999) {

polyfill/lib/intl.mjs

@@ -113,7 +113,7 @@ function formatRange(a, b) {
     }
     const { instant: aa, formatter: aformatter, timeZone: atz } = extractOverrides(a, this);
     const { instant: bb, formatter: bformatter, timeZone: btz } = extractOverrides(b, this);
-    if (atz && btz && ES.TimeZoneToString(atz) !== ES.TimeZoneToString(btz)) {
+    if (atz && btz && !ES.TimeZoneEquals(atz, btz)) {
       throw new RangeError('cannot format range between different time zones');
     }
     if (aa && bb && aformatter && bformatter && aformatter === bformatter) {
@@ -131,7 +131,7 @@ function formatRangeToParts(a, b) {
     }
     const { instant: aa, formatter: aformatter, timeZone: atz } = extractOverrides(a, this);
     const { instant: bb, formatter: bformatter, timeZone: btz } = extractOverrides(b, this);
-    if (atz && btz && ES.TimeZoneToString(atz) !== ES.TimeZoneToString(btz)) {
+    if (atz && btz && !ES.TimeZoneEquals(atz, btz)) {
       throw new RangeError('cannot format range between different time zones');
     }
     if (aa && bb && aformatter && bformatter && aformatter === bformatter) {
@@ -369,7 +369,7 @@ function extractOverrides(temporalObj, main) {
     }
 
     let timeZone = GetSlot(temporalObj, TIME_ZONE);
-    const objTimeZone = ES.TimeZoneToString(timeZone);
+    const objTimeZone = ES.ToString(timeZone);
     if (main[TZ_GIVEN] && main[TZ_GIVEN] !== objTimeZone) {
       throw new RangeError(`timeZone option ${main[TZ_GIVEN]} doesn't match actual time zone ${objTimeZone}`);
     }

polyfill/lib/timezone.mjs

@@ -41,7 +41,7 @@ export class TimeZone {
     }
   }
   get id() {
-    return ES.TimeZoneToString(this);
+    return ES.ToString(this);
   }
   getOffsetNanosecondsFor(instant) {
     if (!ES.IsTemporalTimeZone(this)) throw new TypeError('invalid receiver');
@@ -220,7 +220,7 @@ export class TimeZone {
     return String(GetSlot(this, TIMEZONE_ID));
   }
   toJSON() {
-    return ES.TimeZoneToString(this);
+    return ES.ToString(this);
   }
   static from(item) {
     if (ES.Type(item) === 'Object') {
@@ -241,4 +241,3 @@ DefineIntrinsic('Temporal.TimeZone.prototype.getPlainDateTimeFor', TimeZone.prot
 DefineIntrinsic('Temporal.TimeZone.prototype.getInstantFor', TimeZone.prototype.getInstantFor);
 DefineIntrinsic('Temporal.TimeZone.prototype.getOffsetNanosecondsFor', TimeZone.prototype.getOffsetNanosecondsFor);
 DefineIntrinsic('Temporal.TimeZone.prototype.getOffsetStringFor', TimeZone.prototype.getOffsetStringFor);
-DefineIntrinsic('Temporal.TimeZone.prototype.toString', TimeZone.prototype.toString);

polyfill/lib/zoneddatetime.mjs

@@ -902,7 +902,7 @@ function zonedDateTimeToString(
   );
   let result = `${year}-${month}-${day}T${hour}:${minute}${seconds}`;
   if (showOffset !== 'never') result += ES.GetOffsetStringFor(tz, instant);
-  if (showTimeZone !== 'never') result += `[${ES.TimeZoneToString(tz)}]`;
+  if (showTimeZone !== 'never') result += `[${tz}]`;
   const calendarID = ES.ToString(GetSlot(zdt, CALENDAR));
   result += ES.FormatCalendarAnnotation(calendarID, showCalendar);
   return result;

polyfill/test/TimeZone/prototype/id/no-toString.js

@@ -20,7 +20,5 @@ Object.defineProperty(timeZone, "toString", {
 });
 
 const descriptor = Object.getOwnPropertyDescriptor(Temporal.TimeZone.prototype, "id");
-const result = descriptor.get.call(timeZone);
-assert.sameValue(result, "UTC");
-
+assert.throws(TypeError, () => descriptor.get.call(timeZone));
 assert.compareArray(actual, expected);

polyfill/test/TimeZone/prototype/id/plain-custom-timezone.js

@@ -8,6 +8,7 @@ includes: [compareArray.js]
 
 const actual = [];
 const expected = [
+  "get timeZone[@@toPrimitive]",
   "get timeZone.toString",
   "call timeZone.toString",
 ];
@@ -19,17 +20,24 @@ const timeZone = new Proxy({
   },
 }, {
   has(target, property) {
-    actual.push(`has timeZone.${property}`);
+    if (property === Symbol.toPrimitive) {
+      actual.push('has timeZone[@@toPrimitive]');
+    } else {
+      actual.push(`has timeZone.${property}`);
+    }
     return property in target;
   },
   get(target, property) {
-    actual.push(`get timeZone.${property}`);
+    if (property === Symbol.toPrimitive) {
+      actual.push('get timeZone[@@toPrimitive]');
+    } else {
+      actual.push(`get timeZone.${property}`);
+    }
     return target[property];
   },
 });
 
 const descriptor = Object.getOwnPropertyDescriptor(Temporal.TimeZone.prototype, "id");
 const result = descriptor.get.call(timeZone);
-assert.sameValue(result, "time zone");
-
 assert.compareArray(actual, expected);
+assert.sameValue(result, "time zone");

polyfill/test/TimeZone/prototype/toJSON/custom-tostring-undefined.js

@@ -7,19 +7,31 @@ includes: [compareArray.js]
 ---*/
 
 const actual = [];
-const expected = ['get timeZone.toString'];
+const expected = [
+  'get timeZone[@@toPrimitive]',
+  'get timeZone.toString',
+  'get timeZone.valueOf',
+];
 
 const timeZone = new Proxy(
   {
     toString: undefined
   },
   {
     has(target, property) {
-      actual.push(`has timeZone.${property}`);
+      if (property === Symbol.toPrimitive) {
+        actual.push('has timeZone[@@toPrimitive]');
+      } else {
+        actual.push(`has timeZone.${property}`);
+      }
       return property in target;
     },
     get(target, property) {
-      actual.push(`get timeZone.${property}`);
+      if (property === Symbol.toPrimitive) {
+        actual.push('get timeZone[@@toPrimitive]');
+      } else {
+        actual.push(`get timeZone.${property}`);
+      }
       return target[property];
     }
   }

polyfill/test/TimeZone/prototype/toJSON/tostring-call.js

@@ -7,7 +7,11 @@ includes: [compareArray.js]
 ---*/
 
 const actual = [];
-const expected = ['get timeZone.toString', 'call timeZone.toString'];
+const expected = [
+  'get timeZone[@@toPrimitive]',
+  'get timeZone.toString',
+  'call timeZone.toString',
+];
 
 const timeZone = new Proxy(
   {
@@ -18,11 +22,19 @@ const timeZone = new Proxy(
   },
   {
     has(target, property) {
-      actual.push(`has timeZone.${property}`);
+      if (property === Symbol.toPrimitive) {
+        actual.push('has timeZone[@@toPrimitive]');
+      } else {
+        actual.push(`has timeZone.${property}`);
+      }
       return property in target;
     },
     get(target, property) {
-      actual.push(`get timeZone.${property}`);
+      if (property === Symbol.toPrimitive) {
+        actual.push('get timeZone[@@toPrimitive]');
+      } else {
+        actual.push(`get timeZone.${property}`);
+      }
       return target[property];
     }
   }

polyfill/test/TimeZone/prototype/toJSON/tostring-undefined-custom.js

@@ -7,19 +7,31 @@ includes: [compareArray.js]
 ---*/
 
 const actual = [];
-const expected = ['get timeZone.toString'];
+const expected = [
+  'get timeZone[@@toPrimitive]',
+  'get timeZone.toString',
+  'get timeZone.valueOf',
+];
 
 const timeZone = new Proxy(
   {
     toString: undefined
   },
   {
     has(target, property) {
-      actual.push(`has timeZone.${property}`);
+      if (property === Symbol.toPrimitive) {
+        actual.push('has timeZone[@@toPrimitive]');
+      } else {
+        actual.push(`has timeZone.${property}`);
+      }
       return property in target;
     },
     get(target, property) {
-      actual.push(`get timeZone.${property}`);
+      if (property === Symbol.toPrimitive) {
+        actual.push('get timeZone[@@toPrimitive]');
+      } else {
+        actual.push(`get timeZone.${property}`);
+      }
       return target[property];
     }
   }

polyfill/test/TimeZone/prototype/toJSON/tostring-undefined.js

@@ -8,5 +8,4 @@ esid: sec-temporal.timezone.prototype.tojson
 const tz = Temporal.TimeZone.from('UTC');
 tz.toString = undefined;
 
-const result = tz.toJSON();
-assert.sameValue(result, 'UTC');
+assert.throws(TypeError, () => tz.toJSON());

spec/intl.html

@@ -342,7 +342,7 @@ <h1>PartitionDateTimePattern ( _dateTimeFormat_, _x_ )</h1>
             1. <ins>Let _calendar_ be ? ToString(_x_.[[Calendar]]).</ins>
             1. <ins>If _calendar_ is not *"iso8601"* and not equal to _dateTimeFormat_.[[Calendar]], then</ins>
               1. <ins>Throw a *RangeError* exception.</ins>
-            1. <ins>Let _timeZone_ be ? TimeZoneToString(_x_.[[TimeZone]]).</ins>
+            1. <ins>Let _timeZone_ be ? ToString(_x_.[[TimeZone]]).</ins>
             1. <ins>If _dateTimeFormat_.[[TimeZone]] is not equal to DefaultTimeZone(), and _timeZone_ is not equal to _dateTimeFormat_.[[TimeZone]], then</ins>
               1. <ins>Throw a *RangeError* exception.</ins>
             1. <ins>Let _instant_ be ? CreateTemporalInstant(_x_.[[Nanoseconds]]).</ins>

spec/timezone.html

@@ -118,7 +118,7 @@ <h1>get Temporal.TimeZone.prototype.id</h1>
       </p>
       <emu-alg>
         1. Let _timeZone_ be the *this* value.
-        1. Return ? TimeZoneToString(_timeZone_).
+        1. Return ? ToString(_timeZone_).
       </emu-alg>
     </emu-clause>
 
@@ -297,9 +297,6 @@ <h1>Temporal.TimeZone.prototype.toString ( )</h1>
         1. Perform ? RequireInternalSlot(_timeZone_, [[InitializedTemporalTimeZone]]).
         1. Return _timeZone_.[[Identifier]].
       </emu-alg>
-      <p>
-        This function is the <dfn>%Temporal.TimeZone.prototype.toString%</dfn> intrinsic object.
-      </p>
     </emu-clause>
 
     <emu-clause id="sec-temporal.timezone.prototype.tojson">
@@ -309,7 +306,7 @@ <h1>Temporal.TimeZone.prototype.toJSON ( )</h1>
       </p>
       <emu-alg>
         1. Let _timeZone_ be the *this* value.
-        1. Return ? TimeZoneToString(_timeZone_).
+        1. Return ? ToString(_timeZone_).
       </emu-alg>
     </emu-clause>
   </emu-clause>
@@ -593,24 +590,15 @@ <h1>GetPossibleInstantsFor ( _timeZone_, _dateTime_ )</h1>
       </emu-alg>
     </emu-clause>
 
-    <emu-clause id="sec-temporal-timezonetostring" aoid="TimeZoneToString">
-      <h1>TimeZoneToString ( _timeZone_ )</h1>
-      <emu-alg>
-        1. Let _toString_ be ? Get(_timeZone_, *"toString"*).
-        1. If _toString_ is *undefined*, set _toString_ to %Temporal.TimeZone.prototype.toString%.
-        1. Return be ? ToString(? Call(_toString_, _timeZone_, « »)).
-      </emu-alg>
-    </emu-clause>
-
     <emu-clause id="sec-temporal-comparetimezone" aoid="CompareTimeZone">
       <h1>CompareTimeZone ( _one_, _two_ )</h1>
       <p>
         The abstract operation CompareTimeZone lexicographically compares the
         results of calling `toString()` on its arguments.
       </p>
       <emu-alg>
-        1. Let _calendarOne_ be ? TimeZoneToString(_one_).
-        1. Let _calendarTwo_ be ? TimeZoneToString(_two_).
+        1. Let _timeZoneOne_ be ? ToString(_one_).
+        1. Let _timeZoneTwo_ be ? ToString(_two_).
         1. Let _r_ be the result of performing Abstract Relational Comparison _timeZoneOne_ &lt; _timeZoneTwo_.
         1. If _r_ is *true*, return −1.
         1. Let _r_ be the result of performing Abstract Relational Comparison _timeZoneTwo_ &lt; _timeZoneOne_.
@@ -626,8 +614,8 @@ <h1>TimeZoneEquals ( _one_, _two_ )</h1>
         calling `toString()` on its arguments are equal.
       </p>
       <emu-alg>
-        1. Let _timeZoneOne_ be ? TimeZoneToString(_one_).
-        1. Let _timeZoneTwo_ be ? TimeZoneToString(_two_).
+        1. Let _timeZoneOne_ be ? ToString(_one_).
+        1. Let _timeZoneTwo_ be ? ToString(_two_).
         1. If _timeZoneOne_ is _timeZoneTwo_, return *true*.
         1. Return *false*.
       </emu-alg>

spec/zoneddatetime.html

@@ -1343,10 +1343,11 @@ <h1>TemporalZonedDateTimeToString ( _zonedDateTime_, _precision_, _showCalendar_
         1. If _showTimeZone_ is *"never"*, then
           1. Let _timeZoneString_ be the empty String.
         1. Else,
-          1. Let _timeZoneString_ be ? TimeZoneToString(_timeZone_).
+          1. Let _timeZoneID_ be ? ToString(_timeZone_).
+          1. Let _timeZoneString_ be the string-concatenation of the code unit 0x005B (LEFT SQUARE BRACKET), _timeZoneID_, and the code unit 0x005D (RIGHT SQUARE BRACKET).
         1. Let _calendarID_ be ? ToString(_zonedDateTime_.[[Calendar]]).
         1. Let _calendarString_ be ? FormatCalendarAnnotation(_calendarID_, _showCalendar_).
-        1. Return the string-concatenation of _dateTimeString_, _offsetString_, the code unit 0x005B (LEFT SQUARE BRACKET), _timeZoneString_, the code unit 0x005D (RIGHT SQUARE BRACKET), and _calendarString_.
+        1. Return the string-concatenation of _dateTimeString_, _offsetString_, _timeZoneString_, and _calendarString_.
       </emu-alg>
     </emu-clause>