Temporal: Tests for round() and since()/until() using the same code path

This should produce all the same results (except for a change to weeks
balancing in round(), which is now more consistent with since()/until())
but leads to different observable user code calls.

See tc39/proposal-temporal#2742

test/built-ins/Temporal/Duration/prototype/round/calendar-dateadd-called-with-options-undefined.js

@@ -17,41 +17,26 @@ const relativeTo = new Temporal.ZonedDateTime(0n, timeZone, calendar);
 // Rounding with smallestUnit a calendar unit.
 // The calls come from these paths:
 // Duration.round() ->
-//   RoundDuration ->
-//     MoveRelativeZonedDateTime -> AddZonedDateTime -> calendar.dateAdd()
-//     MoveRelativeDate -> calendar.dateAdd()
-//   BalanceDateDurationRelative -> calendar.dateAdd()
+//   AddZonedDateTime -> calendar.dateAdd()
+//   DifferenceZonedDateTimeWithRounding ->
+//     RoundDuration ->
+//       MoveRelativeZonedDateTime -> AddZonedDateTime -> calendar.dateAdd()
+//       MoveRelativeDate -> calendar.dateAdd() (2x)
+//     BalanceDateDurationRelative -> calendar.dateAdd()
 
-const instance1 = new Temporal.Duration(1, 1, 1, 1, 1);
-instance1.round({ smallestUnit: "weeks", relativeTo });
-assert.sameValue(calendar.dateAddCallCount, 4, "rounding with calendar smallestUnit");
-
-// Rounding with a non-default largestUnit to cover the path in
-// UnbalanceDurationRelative where larger units are converted into smaller
-// units; and with a smallestUnit larger than days to cover the path in
-// RoundDuration where days are converted into larger units.
-// The calls come from these paths:
-// Duration.round() ->
-//   UnbalanceDurationRelative -> MoveRelativeDate -> calendar.dateAdd()
-//   RoundDuration ->  MoveRelativeDate -> calendar.dateAdd() (2x)
-//   BalanceDateDurationRelative -> calendar.dateAdd()
-//   MoveRelativeZonedDateTime -> AddZonedDateTime -> calendar.dateAdd()
-
-calendar.dateAddCallCount = 0;
-
-const instance2 = new Temporal.Duration(0, 1, 1, 1);
-instance2.round({ largestUnit: "weeks", smallestUnit: "weeks", relativeTo });
-assert.sameValue(calendar.dateAddCallCount, 6, "rounding with non-default largestUnit and calendar smallestUnit");
+const instance = new Temporal.Duration(1, 1, 1, 1, 1);
+instance.round({ smallestUnit: "weeks", relativeTo });
+assert.sameValue(calendar.dateAddCallCount, 5, "rounding with calendar smallestUnit");
 
 // Rounding with smallestUnit days only.
 // The calls come from these paths:
 // Duration.round() ->
-//   RoundDuration ->
-//     MoveRelativeZonedDateTime -> AddZonedDateTime -> calendar.dateAdd()
-//   BalanceDateDurationRelative -> calendar.dateAdd()
+//   AddZonedDateTime -> calendar.dateAdd()
+//   DifferenceZonedDateTimeWithRounding ->
+//     RoundDuration -> MoveRelativeZonedDateTime -> AddZonedDateTime -> calendar.dateAdd()
+//     BalanceDateDurationRelative -> calendar.dateAdd()
 
 calendar.dateAddCallCount = 0;
 
-const instance3 = new Temporal.Duration(1, 1, 1, 1, 1);
-instance3.round({ smallestUnit: "days", relativeTo });
+instance.round({ smallestUnit: "days", relativeTo });
 assert.sameValue(calendar.dateAddCallCount, 3, "rounding with days smallestUnit");

test/built-ins/Temporal/Duration/prototype/round/calendar-dateuntil-called-with-singular-largestunit.js

@@ -99,9 +99,9 @@ TemporalHelpers.checkCalendarDateUntilLargestUnitSingular(
     duration.round({ largestUnit, roundingIncrement: 2, roundingMode: 'ceil', relativeTo });
   },
   {
-    years: ["year", "year"],
-    months: ["month", "month"],
-    weeks: ["week", "week"],
+    years: ["year", "year", "year"],
+    months: ["month", "month", "month"],
+    weeks: ["week", "week", "week"],
     days: [],
     hours: [],
     minutes: [],
@@ -123,7 +123,7 @@ TemporalHelpers.checkCalendarDateUntilLargestUnitSingular(
   },
   {
     years: ["year"],
-    months: ["month", "month"],
+    months: ["month"],
     weeks: ["week"],
     days: [],
     hours: [],
@@ -146,9 +146,9 @@ TemporalHelpers.checkCalendarDateUntilLargestUnitSingular(
     const relativeTo = new Temporal.ZonedDateTime(1_000_000_000_000_000_000n, "UTC", calendar);
     duration.round({ largestUnit, smallestUnit: largestUnit, relativeTo });
   }, {
-    years: ["year"],
-    months: ["month"],
-    weeks: ["week", "week"],
+    years: ["year", "year"],
+    months: ["month", "month"],
+    weeks: ["week", "week", "week"],
     days: []
   }
 );

test/built-ins/Temporal/Duration/prototype/round/dateuntil-field.js

@@ -28,8 +28,7 @@ const calendar = new CalendarDateUntilObservable("iso8601");
 const relativeTo = new Temporal.PlainDate(2018, 10, 12, calendar);
 
 const expected = [
-  "call dateUntil",  // UnbalanceDateDurationRelative
-  "call dateUntil",  // BalanceDateDurationRelative
+  "call dateUntil",  // DifferencePlainDateTimeWithRounding -> DifferenceISODateTime
 ];
 
 const years = new Temporal.Duration(2);

test/built-ins/Temporal/Duration/prototype/round/normalized-time-duration-to-days-loop-arbitrarily.js

@@ -18,7 +18,7 @@ info: |
 features: [Temporal]
 ---*/
 
-const duration = Temporal.Duration.from({ days: 1 });
+const duration = new Temporal.Duration(0, 0, 1, 1, 1);
 
 const dayLengthNs = 86400000000000n;
 const dayInstant = new Temporal.Instant(dayLengthNs);
@@ -35,10 +35,11 @@ const relativeTo = new Temporal.ZonedDateTime(0n, timeZone);
 assert.throws(RangeError, () => duration.round({ smallestUnit: "days", relativeTo }), "indefinite loop is prevented");
 assert.sameValue(calls, 5, "getPossibleInstantsFor is not called indefinitely");
   // Expected calls:
-  // RoundDuration -> MoveRelativeZonedDateTime -> AddZonedDateTime (1)
-  // BalanceTimeDurationRelative ->
-  //   AddZonedDateTime (2)
-  //   NormalizedTimeDurationToDays ->
-  //     AddDaysToZonedDateTime (3, step 12)
-  //     AddDaysToZonedDateTime (4, step 15)
-  //     AddDaysToZonedDateTime (5, step 18.d)
+  // AddZonedDateTime (1)
+  // DifferenceZonedDateTimeWithRounding ->
+  //   DifferenceZonedDateTime -> GetInstantFor (2)
+  //   RoundDuration ->
+  //     MoveRelativeZonedDateTime -> AddZonedDateTime (3)
+  //     NormalizedTimeDurationToDays ->
+  //       AddDaysToZonedDateTime (5, step 18)
+  //       AddDaysToZonedDateTime (6, step 21.d)