Editorial: Replace BalanceISODate with AddDaysToISODate

Author: anba

spec/calendar.html

@@ -495,8 +495,8 @@ <h1>
         1. If _calendar_ is *"iso8601"*, then
           1. Let _intermediate_ be BalanceISOYearMonth(_isoDate_.[[Year]] + _duration_.[[Years]], _isoDate_.[[Month]] + _duration_.[[Months]]).
           1. Set _intermediate_ to ? RegulateISODate(_intermediate_.[[Year]], _intermediate_.[[Month]], _isoDate_.[[Day]], _overflow_).
-          1. Let _d_ be _intermediate_.[[Day]] + _duration_.[[Days]] + 7 × _duration_.[[Weeks]].
-          1. Let _result_ be BalanceISODate(_intermediate_.[[Year]], _intermediate_.[[Month]], _d_).
+          1. Let _days_ be _duration_.[[Days]] + 7 × _duration_.[[Weeks]].
+          1. Let _result_ be AddDaysToISODate(_intermediate_, _days_).
         1. Else,
           1. Let _result_ be an implementation-defined ISO Date Record, or throw a *RangeError* exception, as described below.
         1. If ISODateWithinLimits(_result_) is *false*, throw a *RangeError* exception.
@@ -547,18 +547,18 @@ <h1>
           1. Let _weeks_ be 0.
           1. If _largestUnit_ is ~week~, then
             1. Let _candidateWeeks_ be _sign_.
-            1. Set _intermediate_ to BalanceISODate(_constrained_.[[Year]], _constrained_.[[Month]], _constrained_.[[Day]] + 7 × _candidateWeeks_).
+            1. Set _intermediate_ to AddDaysToISODate(_constrained_, 7 × _candidateWeeks_).
             1. Repeat, while ISODateSurpasses(_sign_, _intermediate_.[[Year]], _intermediate_.[[Month]], _intermediate_.[[Day]], _two_) is *false*,
               1. Set _weeks_ to _candidateWeeks_.
               1. Set _candidateWeeks_ to _candidateWeeks_ + sign.
-              1. Set _intermediate_ to BalanceISODate(_intermediate_.[[Year]], _intermediate_.[[Month]], _intermediate_.[[Day]] + 7 × _sign_).
+              1. Set _intermediate_ to AddDaysToISODate(_intermediate_, 7 × _sign_).
           1. Let _days_ be 0.
           1. Let _candidateDays_ be _sign_.
-          1. Set _intermediate_ to BalanceISODate(_constrained_.[[Year]], _constrained_.[[Month]], _constrained_.[[Day]] + 7 × _weeks_ + _candidateDays_).
+          1. Set _intermediate_ to AddDaysToISODate(_constrained_, 7 × _weeks_ + _candidateDays_).
           1. Repeat, while ISODateSurpasses(_sign_, _intermediate_.[[Year]], _intermediate_.[[Month]], _intermediate_.[[Day]], _two_) is *false*,
             1. Set _days_ to _candidateDays_.
             1. Set _candidateDays_ to _candidateDays_ + _sign_.
-            1. Set _intermediate_ to BalanceISODate(_intermediate_.[[Year]], _intermediate_.[[Month]], _intermediate_.[[Day]] + _sign_).
+            1. Set _intermediate_ to AddDaysToISODate(_intermediate_, _sign_).
           1. Return ! CreateDateDurationRecord(_years_, _months_, _weeks_, _days_).
         1. Return an implementation-defined Date Duration Record as described above.
       </emu-alg>

spec/duration.html

@@ -1598,7 +1598,7 @@ <h1>
         1. Else if _unit_ is ~week~, then
           1. Let _yearsMonths_ be ! AdjustDateDurationRecord(_duration_.[[Date]], 0, 0).
           1. Let _weeksStart_ be ? CalendarDateAdd(_calendar_, _isoDateTime_.[[ISODate]], _yearsMonths_, ~constrain~).
-          1. Let _weeksEnd_ be BalanceISODate(_weeksStart_.[[Year]], _weeksStart_.[[Month]], _weeksStart_.[[Day]] + _duration_.[[Date]].[[Days]]).
+          1. Let _weeksEnd_ be AddDaysToISODate(_weeksStart_, _duration_.[[Date]].[[Days]]).
           1. Let _untilResult_ be CalendarDateUntil(_calendar_, _weeksStart_, _weeksEnd_, ~week~).
           1. Let _weeks_ be RoundNumberToIncrement(_duration_.[[Date]].[[Weeks]] + _untilResult_.[[Weeks]], _increment_, ~trunc~).
           1. Let _r1_ be _weeks_.
@@ -1676,7 +1676,7 @@ <h1>
       <emu-alg>
         1. Let _start_ be ? CalendarDateAdd(_calendar_, _isoDateTime_.[[ISODate]], _duration_.[[Date]], ~constrain~).
         1. Let _startDateTime_ be CombineISODateAndTimeRecord(_start_, _isoDateTime_.[[Time]]).
-        1. Let _endDate_ be BalanceISODate(_start_.[[Year]], _start_.[[Month]], _start_.[[Day]] + _sign_).
+        1. Let _endDate_ be AddDaysToISODate(_start_, _sign_).
         1. Let _endDateTime_ be CombineISODateAndTimeRecord(_endDate_, _isoDateTime_.[[Time]]).
         1. Let _startEpochNs_ be ? GetEpochNanosecondsFor(_timeZone_, _startDateTime_, ~compatible~).
         1. Let _endEpochNs_ be ? GetEpochNanosecondsFor(_timeZone_, _endDateTime_, ~compatible~).

spec/plaindate.html

@@ -773,23 +773,22 @@ <h1>
       </emu-alg>
     </emu-clause>
 
-    <emu-clause id="sec-temporal-balanceisodate" type="abstract operation">
+    <emu-clause id="sec-temporal-adddaystoisodate" type="abstract operation">
       <h1>
-        BalanceISODate (
-          _year_: an integer,
-          _month_: an integer,
-          _day_: an integer,
+        AddDaysToISODate (
+          _isoDate_: an ISO Date Record,
+          _days_: an integer,
         ): an ISO Date Record
       </h1>
       <dl class="header">
         <dt>description</dt>
         <dd>
-          It converts the given _year_, _month_, and _day_ into a valid calendar date in the ISO 8601 calendar as given by IsValidISODate, by overflowing out-of-range _month_ or _day_ values into the next-highest unit.
+          It adds _days_ to _isoDate_ into a valid calendar date in the ISO 8601 calendar as given by IsValidISODate, by overflowing out-of-range month or day values into the next-highest unit.
           This date may be outside the range given by ISODateTimeWithinLimits.
         </dd>
       </dl>
       <emu-alg>
-        1. Let _epochDays_ be ISODateToEpochDays(_year_, _month_ - 1, _day_).
+        1. Let _epochDays_ be ISODateToEpochDays(_isoDate_.[[Year]], _isoDate_.[[Month]] - 1, _isoDate_.[[Day]]) + _days_.
         1. Let _ms_ be EpochDaysToEpochMs(_epochDays_, 0).
         1. Return CreateISODateRecord(EpochTimeToEpochYear(_ms_), EpochTimeToMonthInYear(_ms_) + 1, EpochTimeToDate(_ms_)).
       </emu-alg>

spec/plaindatetime.html

@@ -849,7 +849,7 @@ <h1>
       </dl>
       <emu-alg>
         1. Let _balancedTime_ be BalanceTime(_isoDateTime_.[[Time]].[[Hour]], _isoDateTime_.[[Time]].[[Minute]], _isoDateTime_.[[Time]].[[Second]], _isoDateTime_.[[Time]].[[Millisecond]], _isoDateTime_.[[Time]].[[Microsecond]], _isoDateTime_.[[Time]].[[Nanosecond]] + _nanoseconds_).
-        1. Let _balancedDate_ be BalanceISODate(_isoDateTime_.[[ISODate]].[[Year]], _isoDateTime_.[[ISODate]].[[Month]], _isoDateTime_.[[ISODate]].[[Day]] + _balancedTime_.[[Days]]).
+        1. Let _balancedDate_ be AddDaysToISODate(_isoDateTime_.[[ISODate]], _balancedTime_.[[Days]]).
         1. Return CombineISODateAndTimeRecord(_balancedDate_, _balancedTime_).
       </emu-alg>
     </emu-clause>
@@ -935,7 +935,7 @@ <h1>
       <emu-alg>
         1. Assert: ISODateTimeWithinLimits(_isoDateTime_) is *true*.
         1. Let _roundedTime_ be RoundTime(_isoDateTime_.[[Time]], _increment_, _unit_, _roundingMode_).
-        1. Let _balanceResult_ be BalanceISODate(_isoDateTime_.[[ISODate]].[[Year]], _isoDateTime_.[[ISODate]].[[Month]], _isoDateTime_.[[ISODate]].[[Day]] + _roundedTime_.[[Days]]).
+        1. Let _balanceResult_ be AddDaysToISODate(_isoDateTime_.[[ISODate]], _roundedTime_.[[Days]]).
         1. Return CombineISODateAndTimeRecord(_balanceResult_, _roundedTime_).
       </emu-alg>
     </emu-clause>
@@ -963,8 +963,8 @@ <h1>
         1. Let _timeSign_ be TimeDurationSign(_timeDuration_).
         1. Let _dateSign_ be CompareISODate(_isoDateTime1_.[[ISODate]], _isoDateTime2_.[[ISODate]]).
         1. Let _adjustedDate_ be _isoDateTime2_.[[ISODate]].
-        1. If _timeSign_ = _dateSign_, then
-          1. Set _adjustedDate_ to BalanceISODate(_adjustedDate_.[[Year]], _adjustedDate_.[[Month]], _adjustedDate_.[[Day]] + _timeSign_).
+        1. If _timeSign_ = -_dateSign_, then
+          1. Set _adjustedDate_ to AddDaysToISODate(_adjustedDate_, _timeSign_).
           1. Set _timeDuration_ to ! Add24HourDaysToTimeDuration(_timeDuration_, -_timeSign_).
         1. Let _dateLargestUnit_ be LargerOfTwoTemporalUnits(~day~, _largestUnit_).
         1. Let _dateDifference_ be CalendarDateUntil(_calendar_, _isoDateTime1_.[[ISODate]], _adjustedDate_, _dateLargestUnit_).

spec/plainyearmonth.html

@@ -649,7 +649,7 @@ <h1>
         1. If _sign_ &lt; 0, then
           1. Let _oneMonthDuration_ be ! CreateDateDurationRecord(0, 1, 0, 0).
           1. Let _nextMonth_ be ? CalendarDateAdd(_calendar_, _intermediateDate_, _oneMonthDuration_, ~constrain~).
-          1. Let _date_ be BalanceISODate(_nextMonth_.[[Year]], _nextMonth_.[[Month]], _nextMonth_.[[Day]] - 1).
+          1. Let _date_ be AddDaysToISODate(_nextMonth_, -1).
           1. Assert: ISODateWithinLimits(_date_) is *true*.
         1. Else,
           1. Let _date_ be _intermediateDate_.

spec/timezone.html

@@ -320,15 +320,15 @@ <h1>
         1. If _disambiguation_ is ~earlier~, then
           1. Let _timeDuration_ be TimeDurationFromComponents(0, 0, 0, 0, 0, -_nanoseconds_).
           1. Let _earlierTime_ be AddTime(_isoDateTime_.[[Time]], _timeDuration_).
-          1. Let _earlierDate_ be BalanceISODate(_isoDateTime_.[[ISODate]].[[Year]], _isoDateTime_.[[ISODate]].[[Month]], _isoDateTime_.[[ISODate]].[[Day]] + _earlierTime_.[[Days]]).
+          1. Let _earlierDate_ be AddDaysToISODate(_isoDateTime_.[[ISODate]], _earlierTime_.[[Days]]).
           1. Let _earlierDateTime_ be CombineISODateAndTimeRecord(_earlierDate_, _earlierTime_).
           1. Set _possibleEpochNs_ to ? GetPossibleEpochNanoseconds(_timeZone_, _earlierDateTime_).
           1. Assert: _possibleEpochNs_ is not empty.
           1. Return _possibleEpochNs_[0].
         1. Assert: _disambiguation_ is ~compatible~ or ~later~.
         1. Let _timeDuration_ be TimeDurationFromComponents(0, 0, 0, 0, 0, _nanoseconds_).
         1. Let _laterTime_ be AddTime(_isoDateTime_.[[Time]], _timeDuration_).
-        1. Let _laterDate_ be BalanceISODate(_isoDateTime_.[[ISODate]].[[Year]], _isoDateTime_.[[ISODate]].[[Month]], _isoDateTime_.[[ISODate]].[[Day]] + _laterTime_.[[Days]]).
+        1. Let _laterDate_ be AddDaysToISODate(_isoDateTime_.[[ISODate]], _laterTime_.[[Days]]).
         1. Let _laterDateTime_ be CombineISODateAndTimeRecord(_laterDate_, _laterTime_).
         1. Set _possibleEpochNs_ to ? GetPossibleEpochNanoseconds(_timeZone_, _laterDateTime_).
         1. Set _n_ to _possibleEpochNs_'s length.

spec/zoneddatetime.html

@@ -398,7 +398,7 @@ <h1>get Temporal.ZonedDateTime.prototype.hoursInDay</h1>
         1. Let _timeZone_ be _zonedDateTime_.[[TimeZone]].
         1. Let _isoDateTime_ be GetISODateTimeFor(_timeZone_, _zonedDateTime_.[[EpochNanoseconds]]).
         1. Let _today_ be _isoDateTime_.[[ISODate]].
-        1. Let _tomorrow_ be BalanceISODate(_today_.[[Year]], _today_.[[Month]], _today_.[[Day]] + 1).
+        1. Let _tomorrow_ be AddDaysToISODate(_today_, 1).
         1. Let _todayNs_ be ? GetStartOfDay(_timeZone_, _today_).
         1. Let _tomorrowNs_ be ? GetStartOfDay(_timeZone_, _tomorrow_).
         1. Let _diff_ be TimeDurationFromEpochNanosecondsDifference(_tomorrowNs_, _todayNs_).
@@ -651,7 +651,7 @@ <h1>Temporal.ZonedDateTime.prototype.round ( _roundTo_ )</h1>
         1. Let _isoDateTime_ be GetISODateTimeFor(_timeZone_, _thisNs_).
         1. If _smallestUnit_ is ~day~, then
           1. Let _dateStart_ be _isoDateTime_.[[ISODate]].
-          1. Let _dateEnd_ be BalanceISODate(_dateStart_.[[Year]], _dateStart_.[[Month]], _dateStart_.[[Day]] + 1).
+          1. Let _dateEnd_ be AddDaysToISODate(_dateStart_, 1).
           1. Let _startNs_ be ? GetStartOfDay(_timeZone_, _dateStart_).
           1. Assert: _thisNs_ ≥ _startNs_.
           1. Let _endNs_ be ? GetStartOfDay(_timeZone_, _dateEnd_).
@@ -1127,7 +1127,7 @@ <h1>
         1. If TimeDurationSign(_timeDuration_) = -_sign_, set _dayCorrection_ to _dayCorrection_ + 1.
         1. Let _success_ be *false*.
         1. Repeat, while _dayCorrection_ ≤ _maxDayCorrection_ and _success_ is *false*,
-          1. Let _intermediateDate_ be BalanceISODate(_endDateTime_.[[ISODate]].[[Year]], _endDateTime_.[[ISODate]].[[Month]], _endDateTime_.[[ISODate]].[[Day]] - _dayCorrection_ × _sign_).
+          1. Let _intermediateDate_ be AddDaysToISODate(_endDateTime_.[[ISODate]], _dayCorrection_ × -_sign_).
           1. Let _intermediateDateTime_ be CombineISODateAndTimeRecord(_intermediateDate_, _startDateTime_.[[Time]]).
           1. Let _intermediateNs_ be ? GetEpochNanosecondsFor(_timeZone_, _intermediateDateTime_, ~compatible~).
           1. Set _timeDuration_ to TimeDurationFromEpochNanosecondsDifference(_ns2_, _intermediateNs_).