Editorial: Remove ToTemporalDateTimeRoundingIncrement

This operation was already out of sync between the reference code and the
spec text because it was called from entirely different places. Remove it
altogether, inlining it into all of its call sites both in the spec text
and the polyfill.

Author: ptomato

polyfill/lib/duration.mjs

@@ -18,6 +18,7 @@ import {
   SetSlot
 } from './slots.mjs';
 
+const MathFloor = Math.floor;
 const ObjectCreate = Object.create;
 
 export class Duration {
@@ -255,7 +256,23 @@ export class Duration {
       throw new RangeError(`largestUnit ${largestUnit} cannot be smaller than smallestUnit ${smallestUnit}`);
     }
     const roundingMode = ES.ToTemporalRoundingMode(roundTo, 'halfExpand');
-    const roundingIncrement = ES.ToTemporalDateTimeRoundingIncrement(roundTo, smallestUnit);
+
+    const maximumIncrements = {
+      hour: 24,
+      minute: 60,
+      second: 60,
+      millisecond: 1000,
+      microsecond: 1000,
+      nanosecond: 1000
+    };
+    let roundingIncrement = ES.ToTemporalRoundingIncrement(roundTo);
+    const maximum = maximumIncrements[smallestUnit];
+    if (maximum == undefined) {
+      roundingIncrement = MathFloor(roundingIncrement);
+    } else {
+      roundingIncrement = ES.ValidateTemporalRoundingIncrement(roundingIncrement, maximum, false);
+    }
+
     let relativeTo = ES.ToRelativeTemporalObject(roundTo);
 
     ({ years, months, weeks, days } = ES.UnbalanceDurationRelative(

polyfill/lib/ecmascript.mjs

@@ -793,24 +793,6 @@ export const ES = ObjectAssign({}, ES2022, {
     }
     return increment;
   },
-  ToTemporalDateTimeRoundingIncrement: (options, smallestUnit) => {
-    const maximumIncrements = {
-      year: undefined,
-      month: undefined,
-      week: undefined,
-      day: undefined,
-      hour: 24,
-      minute: 60,
-      second: 60,
-      millisecond: 1000,
-      microsecond: 1000,
-      nanosecond: 1000
-    };
-    const increment = ES.ToTemporalRoundingIncrement(options);
-    const maximum = maximumIncrements[smallestUnit];
-    if (maximum == undefined) return MathFloor(increment);
-    return ES.ValidateTemporalRoundingIncrement(increment, maximum, false);
-  },
   ToSecondsStringPrecision: (options) => {
     const smallestUnit = ES.GetTemporalUnit(options, 'smallestUnit', 'time', undefined);
     if (smallestUnit === 'hour') {

spec/abstractops.html

@@ -243,22 +243,6 @@ <h1>
     </emu-alg>
   </emu-clause>
 
-  <emu-clause id="sec-temporal-totemporaldatetimeroundingincrement" aoid="ToTemporalDateTimeRoundingIncrement">
-    <h1>ToTemporalDateTimeRoundingIncrement ( _normalizedOptions_, _smallestUnit_ )</h1>
-    <p>
-      The abstract operation ToTemporalDateTimeRoundingIncrement extracts the value of the property named *"roundingIncrement"* from _normalizedOptions_ and makes sure it is a valid value for the option, setting the correct maximum for rounding Temporal.ZonedDateTime and Temporal.PlainDateTime.
-    </p>
-    <emu-alg>
-      1. If _smallestUnit_ is *"day"*, then
-        1. Let _maximum_ be 1.
-      1. Else,
-        1. Let _maximum_ be ! MaximumTemporalDurationRoundingIncrement(_smallestUnit_).
-        1. Assert: _maximum_ is not *undefined*.
-      1. Let _increment_ be ? ToTemporalRoundingIncrement(_normalizedOptions_).
-      1. Return ? ValidateTemporalRoundingIncrement(_increment_, _maximum_, *false*).
-    </emu-alg>
-  </emu-clause>
-
   <emu-clause id="sec-temporal-tosecondsstringprecision" aoid="ToSecondsStringPrecision">
     <h1>ToSecondsStringPrecision ( _normalizedOptions_ )</h1>
     <p>

spec/plaindatetime.html

@@ -517,7 +517,13 @@ <h1>Temporal.PlainDateTime.prototype.round ( _roundTo_ )</h1>
           1. Set _roundTo_ to ? GetOptionsObject(_roundTo_).
         1. Let _smallestUnit_ be ? GetTemporalUnit(_roundTo_, *"smallestUnit"*, ~time~, ~required~, « *"day"* »).
         1. Let _roundingMode_ be ? ToTemporalRoundingMode(_roundTo_, *"halfExpand"*).
-        1. Let _roundingIncrement_ be ? ToTemporalDateTimeRoundingIncrement(_roundTo_, _smallestUnit_).
+        1. If _smallestUnit_ is *"day"*, then
+          1. Let _maximum_ be 1.
+        1. Else,
+          1. Let _maximum_ be ! MaximumTemporalDurationRoundingIncrement(_smallestUnit_).
+          1. Assert: _maximum_ is not *undefined*.
+        1. Let _roundingIncrement_ be ? ToTemporalRoundingIncrement(_roundTo_).
+        1. Set _roundingIncrement_ to ? ValidateTemporalRoundingIncrement(_roundingIncrement_, _maximum_, *false*).
         1. Let _result_ be ! RoundISODateTime(_dateTime_.[[ISOYear]], _dateTime_.[[ISOMonth]], _dateTime_.[[ISODay]], _dateTime_.[[ISOHour]], _dateTime_.[[ISOMinute]], _dateTime_.[[ISOSecond]], _dateTime_.[[ISOMillisecond]], _dateTime_.[[ISOMicrosecond]], _dateTime_.[[ISONanosecond]], _roundingIncrement_, _smallestUnit_, _roundingMode_).
         1. Return ? CreateTemporalDateTime(_result_.[[Year]], _result_.[[Month]], _result_.[[Day]], _result_.[[Hour]], _result_.[[Minute]], _result_.[[Second]], _result_.[[Millisecond]], _result_.[[Microsecond]], _result_.[[Nanosecond]], _dateTime_.[[Calendar]]).
       </emu-alg>

spec/zoneddatetime.html

@@ -735,7 +735,13 @@ <h1>Temporal.ZonedDateTime.prototype.round ( _roundTo_ )</h1>
           1. Set _roundTo_ to ? GetOptionsObject(_roundTo_).
         1. Let _smallestUnit_ be ? GetTemporalUnit(_roundTo_, *"smallestUnit"*, ~time~, ~required~, « *"day"* »).
         1. Let _roundingMode_ be ? ToTemporalRoundingMode(_roundTo_, *"halfExpand"*).
-        1. Let _roundingIncrement_ be ? ToTemporalDateTimeRoundingIncrement(_roundTo_, _smallestUnit_).
+        1. If _smallestUnit_ is *"day"*, then
+          1. Let _maximum_ be 1.
+        1. Else,
+          1. Let _maximum_ be ! MaximumTemporalDurationRoundingIncrement(_smallestUnit_).
+          1. Assert: _maximum_ is not *undefined*.
+        1. Let _roundingIncrement_ be ? ToTemporalRoundingIncrement(_roundTo_).
+        1. Set _roundingIncrement_ to ? ValidateTemporalRoundingIncrement(_roundingIncrement_, _maximum_, *false*).
         1. Let _timeZone_ be _zonedDateTime_.[[TimeZone]].
         1. Let _instant_ be ! CreateTemporalInstant(_zonedDateTime_.[[Nanoseconds]]).
         1. Let _calendar_ be _zonedDateTime_.[[Calendar]].