Removed invoke() constructors from DayOfWeek and Month (#1)

core/src/commonMain/kotlin/io/islandtime/Date.kt

@@ -36,7 +36,7 @@ class Date(
         year: Int,
         monthNumber: Int,
         day: Int
-    ) : this(year, Month(monthNumber), day)
+    ) : this(year, monthNumber.toMonth(), day)
 
     /**
      * The day of the week
@@ -320,7 +320,7 @@ class Date(
             val dom = marchDoy0 - (marchMonth0 * 306 + 5) / 10 + 1
             yearEst += (marchMonth0 / 10).toLong()
 
-            return Date(yearEst.toInt(), Month(month), dom)
+            return Date(yearEst.toInt(), month, dom)
         }
     }
 }

core/src/commonMain/kotlin/io/islandtime/DateTime.kt

@@ -31,7 +31,7 @@ class DateTime(
         minute: Int,
         second: Int = 0,
         nanosecond: Int = 0
-    ) : this(year, Month(monthNumber), day, hour, minute, second, nanosecond)
+    ) : this(year, monthNumber.toMonth(), day, hour, minute, second, nanosecond)
 
     /**
      * The hour of the day

core/src/commonMain/kotlin/io/islandtime/DayOfWeek.kt

@@ -3,14 +3,24 @@ package io.islandtime
 import io.islandtime.internal.DAYS_IN_WEEK
 import io.islandtime.measures.IntDays
 
-enum class DayOfWeek(val number: Int) {
-    MONDAY(1),
-    TUESDAY(2),
-    WEDNESDAY(3),
-    THURSDAY(4),
-    FRIDAY(5),
-    SATURDAY(6),
-    SUNDAY(7);
+/**
+ * A day of the week.
+ */
+enum class DayOfWeek {
+    MONDAY,
+    TUESDAY,
+    WEDNESDAY,
+    THURSDAY,
+    FRIDAY,
+    SATURDAY,
+    SUNDAY;
+
+    /**
+     * The ISO day of week number.
+     *
+     * The ISO week starts on Monday (1) and ends on Sunday (7).
+     */
+    val number: Int get() = ordinal + 1
 
     operator fun plus(days: IntDays): DayOfWeek {
         val daysToAdd = days.value % DAYS_IN_WEEK
@@ -22,15 +32,18 @@ enum class DayOfWeek(val number: Int) {
     companion object {
         val MIN = MONDAY
         val MAX = SUNDAY
-
-        operator fun invoke(number: Int): DayOfWeek {
-            if (number !in MIN.number..MAX.number) {
-                throw DateTimeException("'$number' is not a valid day of week number")
-            }
-
-            return values()[number - 1]
-        }
     }
 }
 
-fun Int.toDayOfWeek() = DayOfWeek(this)
+/**
+ * Convert an ISO day of week number to a [DayOfWeek].
+ *
+ * The ISO week starts on Monday (1) and ends on Sunday (7).
+ */
+fun Int.toDayOfWeek(): DayOfWeek {
+    if (this !in DayOfWeek.MIN.number..DayOfWeek.MAX.number) {
+        throw DateTimeException("'$this' is not a valid day of week number")
+    }
+
+    return DayOfWeek.values()[this - 1]
+}

core/src/commonMain/kotlin/io/islandtime/Month.kt

@@ -7,57 +7,63 @@ import io.islandtime.measures.days
 /**
  * A month of the year.
  */
-enum class Month(val number: Int) {
-    JANUARY(1) {
+enum class Month {
+    JANUARY {
         override val lengthInCommonYear = 31.days
         override val firstDayOfCommonYear = 1
     },
-    FEBRUARY(2) {
+    FEBRUARY {
         override val lengthInCommonYear = 28.days
         override val lengthInLeapYear = 29.days
         override val firstDayOfCommonYear = 32
     },
-    MARCH(3) {
+    MARCH {
         override val lengthInCommonYear = 31.days
         override val firstDayOfCommonYear = 60
     },
-    APRIL(4) {
+    APRIL {
         override val lengthInCommonYear = 30.days
         override val firstDayOfCommonYear = 91
     },
-    MAY(5) {
+    MAY {
         override val lengthInCommonYear = 31.days
         override val firstDayOfCommonYear = 121
     },
-    JUNE(6) {
+    JUNE {
         override val lengthInCommonYear = 30.days
         override val firstDayOfCommonYear = 152
     },
-    JULY(7) {
+    JULY {
         override val lengthInCommonYear = 31.days
         override val firstDayOfCommonYear = 182
     },
-    AUGUST(8) {
+    AUGUST {
         override val lengthInCommonYear = 31.days
         override val firstDayOfCommonYear = 213
     },
-    SEPTEMBER(9) {
+    SEPTEMBER {
         override val lengthInCommonYear = 30.days
         override val firstDayOfCommonYear = 244
     },
-    OCTOBER(10) {
+    OCTOBER {
         override val lengthInCommonYear = 31.days
         override val firstDayOfCommonYear = 272
     },
-    NOVEMBER(11) {
+    NOVEMBER {
         override val lengthInCommonYear = 30.days
         override val firstDayOfCommonYear = 305
     },
-    DECEMBER(12) {
+    DECEMBER {
         override val lengthInCommonYear = 31.days
         override val firstDayOfCommonYear = 335
     };
 
+
+    /**
+     * Get the ISO month number, from 1-12.
+     */
+    val number: Int get() = ordinal + 1
+
     /**
      * The number of days in the month in a common year.
      */
@@ -147,15 +153,16 @@ enum class Month(val number: Int) {
     companion object {
         val MIN = JANUARY
         val MAX = DECEMBER
-
-        operator fun invoke(number: Int): Month {
-            if (number !in MIN.number..MAX.number) {
-                throw DateTimeException("'$number' is not a valid month of the year")
-            }
-
-            return values()[number - 1]
-        }
     }
 }
 
-fun Int.toMonth() = Month(this)
+/**
+ * Convert an ISO month number (from 1-12) to a [Month].
+ */
+fun Int.toMonth(): Month {
+    if (this !in Month.MIN.number..Month.MAX.number) {
+        throw DateTimeException("'this' is not a valid month of the year")
+    }
+
+    return Month.values()[this - 1]
+}

core/src/commonMain/kotlin/io/islandtime/OffsetDateTime.kt

@@ -50,7 +50,7 @@ class OffsetDateTime(
         second: Int,
         nanosecond: Int,
         offset: UtcOffset
-    ) : this(DateTime(year, Month(monthNumber), dayOfMonth, hour, minute, second, nanosecond), offset)
+    ) : this(DateTime(year, monthNumber.toMonth(), dayOfMonth, hour, minute, second, nanosecond), offset)
 
     inline val date: Date get() = dateTime.date
     inline val time: Time get() = dateTime.time

core/src/commonMain/kotlin/io/islandtime/YearMonth.kt

@@ -157,7 +157,7 @@ inline class YearMonth internal constructor(
  */
 @Suppress("FunctionName")
 fun YearMonth(year: Int, monthNumber: Int): YearMonth {
-    return YearMonth(year, Month(monthNumber))
+    return YearMonth(year, monthNumber.toMonth())
 }
 
 /**
@@ -204,4 +204,4 @@ infix fun Year.at(month: Month) = YearMonth(value, month)
 /**
  * Combine a year and month number to get a [YearMonth]
  */
-fun Year.atMonth(number: Int) = YearMonth(value, Month(number))
+fun Year.atMonth(number: Int) = YearMonth(value, number.toMonth())

core/src/commonTest/kotlin/io/islandtime/DayOfWeekTest.kt

@@ -7,11 +7,6 @@ import kotlin.test.assertEquals
 import kotlin.test.assertFailsWith
 
 class DayOfWeekTest : AbstractIslandTimeTest() {
-    @Test
-    fun `DayOfWeek() returns the day of the week by number, starting with Monday`() {
-        assertEquals(DayOfWeek.WEDNESDAY, DayOfWeek(3))
-    }
-
     @Test
     fun `Int_toDayOfWeek() throws an exception when the number is out of range`() {
         assertFailsWith<DateTimeException> { 0.toDayOfWeek() }
@@ -22,6 +17,7 @@ class DayOfWeekTest : AbstractIslandTimeTest() {
     @Test
     fun `Int_toDayOfWeek() returns the correct day`() {
         assertEquals(DayOfWeek.MONDAY, 1.toDayOfWeek())
+        assertEquals(DayOfWeek.WEDNESDAY, 3.toDayOfWeek())
         assertEquals(DayOfWeek.SUNDAY, 7.toDayOfWeek())
     }
 

core/src/commonTest/kotlin/io/islandtime/MonthTest.kt

@@ -8,11 +8,6 @@ import kotlin.test.assertEquals
 import kotlin.test.assertFailsWith
 
 class MonthTest : AbstractIslandTimeTest() {
-    @Test
-    fun `Month() returns a month by ISO number`() {
-        assertEquals(Month.APRIL, Month(4))
-    }
-
     @Test
     fun `Int_toMonth() throws an exception when the value isn't a valid ISO month number`() {
         assertFailsWith<DateTimeException> { 0.toMonth() }
@@ -22,6 +17,7 @@ class MonthTest : AbstractIslandTimeTest() {
     @Test
     fun `Int_toMonth() gets a Month from an ISO month number when it's in range`() {
         assertEquals(Month.JANUARY, 1.toMonth())
+        assertEquals(Month.APRIL, 4.toMonth())
         assertEquals(Month.DECEMBER, 12.toMonth())
     }
 

core/src/commonTest/kotlin/io/islandtime/YearMonthTest.kt

@@ -16,7 +16,7 @@ class YearMonthTest : AbstractIslandTimeTest() {
 
         assertEquals(
             YearMonth(2018, Month.APRIL),
-            Year(2018) at Month(4)
+            Year(2018) at 4.toMonth()
         )
     }