Cleanup some CalendarUnit usages

core/commonMain/src/Instant.kt

@@ -76,11 +76,6 @@ public fun String.toInstant(): Instant = Instant.parse(this)
  */
 public expect fun Instant.plus(period: DateTimePeriod, zone: TimeZone): Instant
 
-/**
- * @throws DateTimeArithmeticException if this value or the result is too large to fit in [LocalDateTime].
- */
-internal expect fun Instant.plus(value: Int, unit: CalendarUnit, zone: TimeZone): Instant
-
 /**
  * @throws DateTimeArithmeticException if this value or the result is too large to fit in [LocalDateTime].
  */
@@ -97,7 +92,7 @@ public expect fun Instant.periodUntil(other: Instant, zone: TimeZone): DateTimeP
  *
  * @throws DateTimeArithmeticException if this [Instant] or [other] is too large to fit in [LocalDateTime].
  */
-internal expect fun Instant.until(other: Instant, unit: CalendarUnit, zone: TimeZone): Long
+public expect fun Instant.until(other: Instant, unit: DateTimeUnit, zone: TimeZone): Long
 
 /**
  * The return value is clamped to [Int.MAX_VALUE] or [Int.MIN_VALUE] if the result would otherwise cause an arithmetic
@@ -106,7 +101,7 @@ internal expect fun Instant.until(other: Instant, unit: CalendarUnit, zone: Time
  * @throws DateTimeArithmeticException if this [Instant] or [other] is too large to fit in [LocalDateTime].
  */
 public fun Instant.daysUntil(other: Instant, zone: TimeZone): Int =
-    until(other, CalendarUnit.DAY, zone).clampToInt()
+    until(other, DateTimeUnit.DAY, zone).clampToInt()
 
 /**
  * The return value is clamped to [Int.MAX_VALUE] or [Int.MIN_VALUE] if the result would otherwise cause an arithmetic
@@ -115,7 +110,7 @@ public fun Instant.daysUntil(other: Instant, zone: TimeZone): Int =
  * @throws DateTimeArithmeticException if this [Instant] or [other] is too large to fit in [LocalDateTime].
  */
 public fun Instant.monthsUntil(other: Instant, zone: TimeZone): Int =
-    until(other, CalendarUnit.MONTH, zone).clampToInt()
+    until(other, DateTimeUnit.MONTH, zone).clampToInt()
 
 /**
  * The return value is clamped to [Int.MAX_VALUE] or [Int.MIN_VALUE] if the result would otherwise cause an arithmetic
@@ -124,23 +119,32 @@ public fun Instant.monthsUntil(other: Instant, zone: TimeZone): Int =
  * @throws DateTimeArithmeticException if this [Instant] or [other] is too large to fit in [LocalDateTime].
  */
 public fun Instant.yearsUntil(other: Instant, zone: TimeZone): Int =
-    until(other, CalendarUnit.YEAR, zone).clampToInt()
+    until(other, DateTimeUnit.YEAR, zone).clampToInt()
 
 private fun Long.clampToInt(): Int =
     if (this > Int.MAX_VALUE) Int.MAX_VALUE else if (this < Int.MIN_VALUE) Int.MIN_VALUE else toInt()
 
 public fun Instant.minus(other: Instant, zone: TimeZone): DateTimePeriod = other.periodUntil(this, zone)
 
 
-
+/**
+ * @throws DateTimeArithmeticException if this value or the result is too large to fit in [LocalDateTime].
+ */
 public fun Instant.plus(unit: DateTimeUnit, zone: TimeZone): Instant =
         plus(unit.calendarScale, unit.calendarUnit, zone)
+
+// TODO: safeMultiply
+/**
+ * @throws DateTimeArithmeticException if this value or the result is too large to fit in [LocalDateTime].
+ */
 public fun Instant.plus(value: Int, unit: DateTimeUnit, zone: TimeZone): Instant =
         plus(value * unit.calendarScale, unit.calendarUnit, zone)
+
+/**
+ * @throws DateTimeArithmeticException if this value or the result is too large to fit in [LocalDateTime].
+ */
 public fun Instant.plus(value: Long, unit: DateTimeUnit, zone: TimeZone): Instant =
         plus(value * unit.calendarScale, unit.calendarUnit, zone)
 
-public fun Instant.until(other: Instant, unit: DateTimeUnit, zone: TimeZone): Long =
-        until(other, unit.calendarUnit, zone) / unit.calendarScale
 
 public fun Instant.minus(other: Instant, unit: DateTimeUnit, zone: TimeZone): Long = other.until(this, unit, zone)

core/jsMain/src/Instant.kt

@@ -77,19 +77,6 @@ public actual fun Instant.plus(period: DateTimePeriod, zone: TimeZone): Instant
     }.toInstant().let(::Instant)
 }
 
-internal actual fun Instant.plus(value: Int, unit: CalendarUnit, zone: TimeZone): Instant =
-        when (unit) {
-            CalendarUnit.YEAR -> this.value.atZone(zone.zoneId).plusYears(value).toInstant()
-            CalendarUnit.MONTH -> this.value.atZone(zone.zoneId).plusMonths(value).toInstant()
-            CalendarUnit.DAY -> this.value.atZone(zone.zoneId).plusDays(value).let { it as ZonedDateTime }.toInstant()
-            CalendarUnit.HOUR -> this.value.atZone(zone.zoneId).plusHours(value).toInstant()
-            CalendarUnit.MINUTE -> this.value.atZone(zone.zoneId).plusMinutes(value).toInstant()
-            CalendarUnit.SECOND -> this.value.plusSeconds(value)
-            CalendarUnit.MILLISECOND -> this.value.plusMillis(value)
-            CalendarUnit.MICROSECOND -> this.value.plusNanos(value * 1000)
-            CalendarUnit.NANOSECOND -> this.value.plusNanos(value)
-        }.let(::Instant)
-
 internal actual fun Instant.plus(value: Long, unit: CalendarUnit, zone: TimeZone): Instant =
         when (unit) {
             CalendarUnit.YEAR -> this.value.atZone(zone.zoneId).plusYears(value).toInstant()
@@ -116,9 +103,8 @@ public actual fun Instant.periodUntil(other: Instant, zone: TimeZone): DateTimeP
         return DateTimePeriod((months / 12).toInt(), (months % 12).toInt(), days.toInt(), hours, minutes, seconds.toLong(), nanoseconds.toLong())
     }
 }
-
-internal actual fun Instant.until(other: Instant, unit: CalendarUnit, zone: TimeZone): Long =
-        until(other, unit.toChronoUnit(), zone.zoneId)
+public actual fun Instant.until(other: Instant, unit: DateTimeUnit, zone: TimeZone): Long =
+        until(other, unit.calendarUnit.toChronoUnit(), zone.zoneId) / unit.calendarScale
 
 private fun Instant.until(other: Instant, unit: ChronoUnit, zone: ZoneId): Long =
         this.value.atZone(zone).until(other.value.atZone(zone), unit).toLong()

core/jvmMain/src/Instant.kt

@@ -71,9 +71,6 @@ public actual fun Instant.plus(period: DateTimePeriod, zone: TimeZone): Instant
     }.toInstant().let(::Instant)
 }
 
-internal actual fun Instant.plus(value: Int, unit: CalendarUnit, zone: TimeZone): Instant =
-        plus(value.toLong(), unit, zone)
-
 internal actual fun Instant.plus(value: Long, unit: CalendarUnit, zone: TimeZone): Instant =
         when (unit) {
             CalendarUnit.YEAR -> this.value.atZone(zone.zoneId).plusYears(value).toInstant()
@@ -101,8 +98,8 @@ public actual fun Instant.periodUntil(other: Instant, zone: TimeZone): DateTimeP
     }
 }
 
-internal actual fun Instant.until(other: Instant, unit: CalendarUnit, zone: TimeZone): Long =
-        until(other, unit.toChronoUnit(), zone.zoneId)
+public actual fun Instant.until(other: Instant, unit: DateTimeUnit, zone: TimeZone): Long =
+        until(other, unit.calendarUnit.toChronoUnit(), zone.zoneId) / unit.calendarScale
 
 private fun Instant.until(other: Instant, unit: ChronoUnit, zone: ZoneId): Long =
         this.value.atZone(zone).until(other.value.atZone(zone), unit)

core/nativeMain/src/Instant.kt

@@ -299,9 +299,6 @@ actual fun Instant.plus(period: DateTimePeriod, zone: TimeZone): Instant = try {
     throw DateTimeArithmeticException("Boundaries of Instant exceeded when adding CalendarPeriod", e)
 }
 
-internal actual fun Instant.plus(value: Int, unit: CalendarUnit, zone: TimeZone): Instant =
-    plus(value.toLong(), unit, zone)
-
 internal actual fun Instant.plus(value: Long, unit: CalendarUnit, zone: TimeZone): Instant = try {
     when (unit) {
         CalendarUnit.YEAR -> toZonedLocalDateTimeFailing(zone).plusYears(value).toInstant()
@@ -352,9 +349,10 @@ actual fun Instant.periodUntil(other: Instant, zone: TimeZone): DateTimePeriod {
     }
 }
 
-internal actual fun Instant.until(other: Instant, unit: CalendarUnit, zone: TimeZone): Long =
+public actual fun Instant.until(other: Instant, unit: DateTimeUnit, zone: TimeZone): Long =
     try {
-        toZonedLocalDateTimeFailing(zone).until(other.toZonedLocalDateTimeFailing(zone), unit)
+        // TODO: inline 'until' here and simplify operation for time-based units
+        toZonedLocalDateTimeFailing(zone).until(other.toZonedLocalDateTimeFailing(zone), unit.calendarUnit) / unit.calendarScale
     } catch (e: ArithmeticException) {
         if (this < other) Long.MAX_VALUE else Long.MIN_VALUE
     }

core/nativeMain/src/ZonedDateTime.kt

@@ -70,6 +70,8 @@ internal fun Instant.toZonedLocalDateTime(zone: TimeZone): ZonedDateTime {
  * @throws DateTimeArithmeticException if setting [other] to the offset of [this] leads to exceeding boundaries of
  * [LocalDateTime].
  */
+
+// TODO: use DateTimeUnit
 internal fun ZonedDateTime.until(other: ZonedDateTime, unit: CalendarUnit): Long =
     when (unit) {
         // if the time unit is date-based, the offsets are disregarded and only the dates and times are compared.