Update Instant.toZonedDateTime{,ISO}.

docs/cookbook/nextWeeklyOccurrence.mjs

@@ -21,7 +21,7 @@ function nextWeeklyOccurrence(now, weekday, eventTime, eventTimeZone) {
     nextOccurrence = nextOccurrence.add({ days: 7 });
   }
 
-  return eventTimeZone.getInstantFor(nextOccurrence).toZonedDateTime(now.timeZone, now.calendar).toDateTime();
+  return eventTimeZone.getInstantFor(nextOccurrence).toZonedDateTime(now).toDateTime();
 }
 
 // "Weekly on Thursdays at 08:45 California time":

polyfill/lib/instant.mjs

@@ -233,16 +233,33 @@ export class Instant {
   valueOf() {
     throw new TypeError('use compare() or equals() to compare Temporal.Instant');
   }
-  toZonedDateTime(temporalTimeZoneLike, calendarLike) {
+  toZonedDateTime(item) {
     if (!ES.IsTemporalInstant(this)) throw new TypeError('invalid receiver');
-    const timeZone = ES.ToTemporalTimeZone(temporalTimeZoneLike);
+    if (ES.Type(item) !== 'Object') {
+      throw new TypeError('invalid argument in toZonedDateTime');
+    }
+    const calendarLike = item.calendar;
+    if (calendarLike === undefined) {
+      throw new TypeError('missing calendar property in toZonedDateTime');
+    }
     const calendar = ES.ToTemporalCalendar(calendarLike);
+    const temporalTimeZoneLike = item.timeZone;
+    if (temporalTimeZoneLike === undefined) {
+      throw new TypeError('missing timeZone property in toZonedDateTime');
+    }
+    const timeZone = ES.ToTemporalTimeZone(temporalTimeZoneLike);
     const TemporalZonedDateTime = GetIntrinsic('%Temporal.ZonedDateTime%');
     return new TemporalZonedDateTime(GetSlot(this, EPOCHNANOSECONDS), timeZone, calendar);
   }
-  toZonedDateTimeISO(temporalTimeZoneLike) {
+  toZonedDateTimeISO(item) {
     if (!ES.IsTemporalInstant(this)) throw new TypeError('invalid receiver');
-    const timeZone = ES.ToTemporalTimeZone(temporalTimeZoneLike);
+    if (ES.Type(item) === 'Object') {
+      const timeZoneProperty = item.timeZone;
+      if (timeZoneProperty !== undefined) {
+        item = timeZoneProperty;
+      }
+    }
+    const timeZone = ES.ToTemporalTimeZone(item);
     const calendar = GetISO8601Calendar();
     const TemporalZonedDateTime = GetIntrinsic('%Temporal.ZonedDateTime%');
     return new TemporalZonedDateTime(GetSlot(this, EPOCHNANOSECONDS), timeZone, calendar);

polyfill/test/Instant/prototype/toZonedDateTime/calendar-convert.js

@@ -24,7 +24,7 @@ for (const [input, output] of values) {
     return calendar;
   };
 
-  const zdt = instant.toZonedDateTime("UTC", input);
+  const zdt = instant.toZonedDateTime({ timeZone: "UTC", calendar: input });
   assert.sameValue(called, 1);
   assert.sameValue(zdt.calendar, calendar);
 }
@@ -33,4 +33,4 @@ Temporal.Calendar.from = function() {
   throw new Test262Error("Should not call Calendar.from");
 };
 
-assert.throws(TypeError, () => instant.toZonedDateTime("UTC", Symbol()));
+assert.throws(TypeError, () => instant.toZonedDateTime({ timeZone: "UTC", calendar: Symbol() }));

polyfill/test/Instant/prototype/toZonedDateTime/calendar-from-invalid-result.js

@@ -26,6 +26,6 @@ for (const [value, description] of values) {
     return value;
   };
 
-  assert.throws(TypeError, () => instant.toZonedDateTime(timeZone, "test"), description);
+  assert.throws(TypeError, () => instant.toZonedDateTime({ timeZone, calendar: "test" }), description);
   assert.sameValue(called, 1);
 }

polyfill/test/Instant/prototype/toZonedDateTime/calendar-from-undefined.js

@@ -37,7 +37,7 @@ Object.defineProperty(Temporal.Calendar, "from", {
   },
 });
 
-const result = instant.toZonedDateTime(timeZone, "japanese");
+const result = instant.toZonedDateTime({ timeZone, calendar: "japanese" });
 assert.sameValue(result.epochNanoseconds, instant.epochNanoseconds);
 assert.sameValue(result.calendar instanceof Temporal.Calendar, true);
 assert.sameValue(result.calendar.id, "japanese");

polyfill/test/Instant/prototype/toZonedDateTime/calendar-function.js

@@ -35,7 +35,7 @@ Object.defineProperty(Temporal.Calendar, "from", {
   },
 });
 
-const result = instant.toZonedDateTime(timeZone, calendar);
+const result = instant.toZonedDateTime({ timeZone, calendar });
 assert.sameValue(result.epochNanoseconds, instant.epochNanoseconds);
 assert.sameValue(result.calendar, calendar);
 

polyfill/test/Instant/prototype/toZonedDateTime/calendar-object.js

@@ -35,7 +35,7 @@ Object.defineProperty(Temporal.Calendar, "from", {
   },
 });
 
-const result = instant.toZonedDateTime(timeZone, calendar);
+const result = instant.toZonedDateTime({ timeZone, calendar });
 assert.sameValue(result.epochNanoseconds, instant.epochNanoseconds);
 assert.sameValue(result.calendar, calendar);
 

polyfill/test/Instant/prototype/toZonedDateTime/calendar.js

@@ -8,10 +8,10 @@ includes: [compareArray.js]
 
 const actual = [];
 const expected = [
-  "get Temporal.TimeZone.from",
-  "call Temporal.TimeZone.from",
   "get Temporal.Calendar.from",
   "call Temporal.Calendar.from",
+  "get Temporal.TimeZone.from",
+  "call Temporal.TimeZone.from",
 ];
 
 const instant = Temporal.Instant.from("1975-02-02T14:25:36.123456789Z");
@@ -57,7 +57,7 @@ Object.defineProperty(Temporal.Calendar, "from", {
   },
 });
 
-const result = instant.toZonedDateTime("UTC", "iso8601");
+const result = instant.toZonedDateTime({ timeZone: "UTC", calendar: "iso8601" });
 assert.sameValue(result.epochNanoseconds, instant.epochNanoseconds);
 assert.sameValue(result.calendar, calendar);
 

polyfill/test/Instant/prototype/toZonedDateTime/length.js

@@ -16,7 +16,7 @@ includes: [propertyHelper.js]
 ---*/
 
 verifyProperty(Temporal.Instant.prototype.toZonedDateTime, "length", {
-  value: 2,
+  value: 1,
   writable: false,
   enumerable: false,
   configurable: true,

polyfill/test/Instant/prototype/toZonedDateTime/plain-custom-timezone.js

@@ -28,7 +28,7 @@ const timeZone = new Proxy({
   },
 });
 
-const result = instant.toZonedDateTime(timeZone, calendar);
+const result = instant.toZonedDateTime({ timeZone, calendar });
 assert.sameValue(result.epochNanoseconds, instant.epochNanoseconds);
 
 assert.compareArray(actual, expected);

polyfill/test/instant.mjs

@@ -1307,20 +1307,20 @@ describe('Instant', () => {
   describe('Instant.toZonedDateTime() works', () => {
     const inst = Instant.from('1976-11-18T14:23:30.123456789Z');
     it('throws without parameter', () => {
-      throws(() => inst.toZonedDateTime(), RangeError);
+      throws(() => inst.toZonedDateTime(), TypeError);
     });
-    it('throws with only one parameter', () => {
-      throws(() => inst.toZonedDateTime('Asia/Singapore'));
+    it('throws with a string parameter', () => {
+      throws(() => inst.toZonedDateTime('Asia/Singapore'), TypeError);
     });
     it('time zone parameter UTC', () => {
-      const tz = Temporal.TimeZone.from('UTC');
-      const zdt = inst.toZonedDateTime(tz, 'gregory');
+      const timeZone = Temporal.TimeZone.from('UTC');
+      const zdt = inst.toZonedDateTime({ timeZone, calendar: 'gregory' });
       equal(inst.epochNanoseconds, zdt.epochNanoseconds);
       equal(`${zdt}`, '1976-11-18T14:23:30.123456789+00:00[UTC][c=gregory]');
     });
     it('time zone parameter non-UTC', () => {
-      const tz = Temporal.TimeZone.from('America/New_York');
-      const zdt = inst.toZonedDateTime(tz, 'gregory');
+      const timeZone = Temporal.TimeZone.from('America/New_York');
+      const zdt = inst.toZonedDateTime({ timeZone, calendar: 'gregory' });
       equal(inst.epochNanoseconds, zdt.epochNanoseconds);
       equal(`${zdt}`, '1976-11-18T09:23:30.123456789-05:00[America/New_York][c=gregory]');
     });

polyfill/test/zoneddatetime.mjs

@@ -1286,7 +1286,10 @@ describe('ZonedDateTime', () => {
       equal(`${zdt.toDate()}`, '2019-10-29');
     });
     it('preserves the calendar', () => {
-      const zdt = Temporal.Instant.from('2019-10-29T09:46:38.271986102Z').toZonedDateTime(tz, 'gregory');
+      const zdt = Temporal.Instant.from('2019-10-29T09:46:38.271986102Z').toZonedDateTime({
+        timeZone: tz,
+        calendar: 'gregory'
+      });
       equal(zdt.toDate().calendar.id, 'gregory');
     });
   });
@@ -1302,7 +1305,10 @@ describe('ZonedDateTime', () => {
       equal(`${zdt.toYearMonth()}`, '2019-10');
     });
     it('preserves the calendar', () => {
-      const zdt = Temporal.Instant.from('2019-10-29T09:46:38.271986102Z').toZonedDateTime(tz, 'gregory');
+      const zdt = Temporal.Instant.from('2019-10-29T09:46:38.271986102Z').toZonedDateTime({
+        timeZone: tz,
+        calendar: 'gregory'
+      });
       equal(zdt.toYearMonth().calendar.id, 'gregory');
     });
   });
@@ -1312,7 +1318,10 @@ describe('ZonedDateTime', () => {
       equal(`${zdt.toMonthDay()}`, '10-29');
     });
     it('preserves the calendar', () => {
-      const zdt = Temporal.Instant.from('2019-10-29T09:46:38.271986102Z').toZonedDateTime(tz, 'gregory');
+      const zdt = Temporal.Instant.from('2019-10-29T09:46:38.271986102Z').toZonedDateTime({
+        timeZone: tz,
+        calendar: 'gregory'
+      });
       equal(zdt.toMonthDay().calendar.id, 'gregory');
     });
   });

spec/instant.html

@@ -446,30 +446,42 @@ <h1>Temporal.Instant.prototype.valueOf ( )</h1>
     </emu-clause>
 
     <emu-clause id="sec-temporal.instant.prototype.tozoneddatetime">
-      <h1>Temporal.Instant.prototype.toZonedDateTime ( _temporalTimeZoneLike_, _calendarLike_ )</h1>
+      <h1>Temporal.Instant.prototype.toZonedDateTime ( _item_ )</h1>
       <p>
-        The `toZonedDateTime` method takes two arguments, _temporalTimeZoneLike_ and _calendarLike_.
+        The `toZonedDateTime` method takes one argument _item_.
         The following steps are taken:
       </p>
       <emu-alg>
         1. Let _instant_ be the *this* value.
         1. Perform ? RequireInternalSlot(_instant_, [[InitializedTemporalInstant]]).
-        1. Let _timeZone_ be ? ToTemporalTimeZone(_temporalTimeZoneLike_).
+        1. If Type(_item_) is not Object, then
+          1. Throw a *TypeError* exception.
+        1. Let _calendarLike_ be ? Get(_item_, *"calendar"*).
+        1. If _calendarLike_ is *undefined*, then
+          1. Throw a *TypeError* exception.
         1. Let _calendar_ be ? ToTemporalCalendar(_calendarLike_).
+        1. Let _temporalTimeZoneLike_ be ? Get(_item_, *"timeZone"*).
+        1. If _temporalTimeZoneLike_ is *undefined*, then
+          1. Throw a *TypeError* exception.
+        1. Let _timeZone_ be ? ToTemporalTimeZone(_temporalTimeZoneLike_).
         1. Return ? CreateTemporalZonedDateTime(_instant_.[[Nanoseconds]], _timeZone_, _calendar_).
       </emu-alg>
     </emu-clause>
 
     <emu-clause id="sec-temporal.instant.prototype.tozoneddatetimeiso">
-      <h1>Temporal.Instant.prototype.toZonedDateTimeISO ( _temporalTimeZoneLike_ )</h1>
+      <h1>Temporal.Instant.prototype.toZonedDateTimeISO ( _item_ )</h1>
       <p>
-        The `toZonedDateTimeISO` method takes one argument _temporalTimeZoneLike_.
+        The `toZonedDateTimeISO` method takes one argument _item_.
         The following steps are taken:
       </p>
       <emu-alg>
         1. Let _instant_ be the *this* value.
         1. Perform ? RequireInternalSlot(_instant_, [[InitializedTemporalInstant]]).
-        1. Let _timeZone_ be ? ToTemporalTimeZone(_temporalTimeZoneLike_).
+        1. If Type(_item_) is Object, then
+          1. Let _timeZoneProperty_ be ? Get(_item_, *"timeZone"*).
+          1. If _timeZoneProperty_ is not *undefined*, then
+            1. Set _item_ to _timeZoneProperty_.
+        1. Let _timeZone_ be ? ToTemporalTimeZone(_item_).
         1. Let _calendar_ be ? GetISO8601Calendar().
         1. Return ? CreateTemporalZonedDateTime(_instant_.[[Nanoseconds]], _timeZone_, _calendar_).
       </emu-alg>