Remove implicit defaultLocale() from APIs, expose locale creation by …

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

@@ -6,7 +6,6 @@ import io.islandtime.format.DateTimeTextProvider
 import io.islandtime.format.TextStyle
 import io.islandtime.internal.DAYS_PER_WEEK
 import io.islandtime.locale.Locale
-import io.islandtime.locale.defaultLocale
 import io.islandtime.measures.IntDays
 import io.islandtime.measures.LongDays
 import io.islandtime.measures.days
@@ -43,15 +42,15 @@ enum class DayOfWeek {
     fun number(locale: Locale): Int = (this - (locale.firstDayOfWeek.number - 1).days).number
 
     /**
-     * The localized name of the day, if available for the locale in the specified style. The result depends on the
+     * The localized name of the day, if available for the [locale] in the specified style. The result depends on the
      * configured [DateTimeTextProvider] and may differ between platforms.
      *
      * @param style the style of text
      * @param locale the locale
      * @return the localized name or `null` if unavailable for the specified locale
      * @see displayName
      */
-    fun localizedName(style: TextStyle, locale: Locale = defaultLocale()): String? {
+    fun localizedName(style: TextStyle, locale: Locale): String? {
         return DateTimeTextProvider.dayOfWeekTextFor(number.toLong(), style, locale)
     }
 
@@ -66,7 +65,7 @@ enum class DayOfWeek {
      * @return the localized name or [number] if unavailable for the specified locale
      * @see localizedName
      */
-    fun displayName(style: TextStyle, locale: Locale = defaultLocale()): String {
+    fun displayName(style: TextStyle, locale: Locale): String {
         return localizedName(style, locale) ?: number.toString()
     }
 

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

@@ -3,7 +3,6 @@ package io.islandtime
 import io.islandtime.format.DateTimeTextProvider
 import io.islandtime.format.TextStyle
 import io.islandtime.locale.Locale
-import io.islandtime.locale.defaultLocale
 import io.islandtime.measures.IntDays
 import io.islandtime.measures.IntMonths
 import io.islandtime.measures.LongMonths
@@ -99,15 +98,15 @@ enum class Month {
         }
 
     /**
-     * The localized name of the month, if available for the locale in the specified style. The result depends on the
+     * The localized name of the month, if available for the [locale] in the specified style. The result depends on the
      * configured [DateTimeTextProvider] and may differ between platforms.
      *
      * @param style the style of text
      * @param locale the locale
      * @return the localized name or `null` if unavailable for the specified locale
      * @see displayName
      */
-    fun localizedName(style: TextStyle, locale: Locale = defaultLocale()): String? {
+    fun localizedName(style: TextStyle, locale: Locale): String? {
         return DateTimeTextProvider.monthTextFor(number.toLong(), style, locale)
     }
 
@@ -122,7 +121,7 @@ enum class Month {
      * @return the localized name or [number] if unavailable for the specified locale
      * @see localizedName
      */
-    fun displayName(style: TextStyle, locale: Locale = defaultLocale()): String {
+    fun displayName(style: TextStyle, locale: Locale): String {
         return localizedName(style, locale) ?: number.toString()
     }
 

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

@@ -6,7 +6,6 @@ import io.islandtime.format.TimeZoneTextProvider
 import io.islandtime.format.TimeZoneTextStyle
 import io.islandtime.internal.systemDefaultTimeZone
 import io.islandtime.locale.Locale
-import io.islandtime.locale.defaultLocale
 import io.islandtime.measures.nanoseconds
 import io.islandtime.measures.seconds
 import io.islandtime.parser.*
@@ -56,7 +55,7 @@ sealed class TimeZone : Comparable<TimeZone> {
     fun validated(): TimeZone = apply { validate() }
 
     /**
-     * The localized name of this time zone, if available for the locale in the specified style. The result depends on
+     * The localized name of this time zone, if available for the [locale] in the specified style. The result depends on
      * the configured [TimeZoneTextProvider] and may differ between platforms.
      *
      * Example output for the "America/New_York" ID and "en-US" locale:
@@ -69,13 +68,13 @@ sealed class TimeZone : Comparable<TimeZone> {
      *
      * @see displayName
      */
-    fun localizedName(style: TimeZoneTextStyle, locale: Locale = defaultLocale()): String? {
+    fun localizedName(style: TimeZoneTextStyle, locale: Locale): String? {
         return TimeZoneTextProvider.timeZoneTextFor(this, style, locale)
     }
 
     /**
      * A textual representation of this time zone, suitable for display purposes. The localized name will be returned,
-     * if available for the locale in the specified style. If not, the [id] will be returned instead.
+     * if available for the [locale] in the specified style. If not, the [id] will be returned instead.
      *
      * The result depends on the configured [TimeZoneTextProvider] and may differ between platforms.
      *
@@ -90,7 +89,7 @@ sealed class TimeZone : Comparable<TimeZone> {
      * @see localizedName
      * @see id
      */
-    fun displayName(style: TimeZoneTextStyle, locale: Locale = defaultLocale()): String {
+    fun displayName(style: TimeZoneTextStyle, locale: Locale): String {
         return localizedName(style, locale) ?: id
     }
 

core/src/commonMain/kotlin/io/islandtime/format/NumberStyle.kt

@@ -3,7 +3,7 @@ package io.islandtime.format
 import io.islandtime.locale.Locale
 
 /**
- * Defines the set of characters that should be used when parsing or formatting numbers.
+ * The set of characters that should be used when parsing or formatting numbers.
  *
  * @property zeroDigit The character that represents zero.
  * @property plusSign A list of allowed plus sign characters. The first element will be used when formatting.

core/src/commonMain/kotlin/io/islandtime/locale/Locale.kt

@@ -8,8 +8,13 @@ package io.islandtime.locale
 expect class Locale
 
 /**
- * Get the current [Locale].
+ * Gets the current [Locale].
+ *
+ * On the JVM, the `Category` is not used in order to support older Android versions.
  */
 expect fun defaultLocale(): Locale
 
-internal expect fun localeOf(identifier: String): Locale
+/**
+ * Converts an IETF BCP 47 language tag, such as "en-US" or "de-DE", to a [Locale].
+ */
+expect fun String.toLocale(): Locale

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

@@ -5,7 +5,7 @@ import io.islandtime.Time.Companion.MIDNIGHT
 import io.islandtime.calendar.WeekSettings
 import io.islandtime.calendar.WeekSettings.Companion.ISO
 import io.islandtime.calendar.WeekSettings.Companion.SUNDAY_START
-import io.islandtime.locale.localeOf
+import io.islandtime.locale.toLocale
 import io.islandtime.measures.hours
 import io.islandtime.measures.days
 import io.islandtime.measures.weeks
@@ -18,7 +18,7 @@ import kotlin.test.assertTrue
 
 class DatePropertiesTest : AbstractIslandTimeTest() {
     @Suppress("PrivatePropertyName")
-    private val en_US = localeOf("en-US")
+    private val en_US = "en-US".toLocale()
 
     private val nyZone = TimeZone("America/New_York")
 

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

@@ -2,7 +2,7 @@ package io.islandtime
 
 import io.islandtime.calendar.WeekSettings
 import io.islandtime.format.TextStyle
-import io.islandtime.locale.localeOf
+import io.islandtime.locale.toLocale
 import io.islandtime.measures.days
 import io.islandtime.test.AbstractIslandTimeTest
 import kotlin.test.Test
@@ -11,9 +11,9 @@ import kotlin.test.assertFailsWith
 
 @Suppress("PrivatePropertyName")
 class DayOfWeekTest : AbstractIslandTimeTest() {
-    private val en_US = localeOf("en-US")
-    private val de_DE = localeOf("de-DE")
-    private val ar_EG = localeOf("ar-EG")
+    private val en_US = "en-US".toLocale()
+    private val de_DE = "de-DE".toLocale()
+    private val ar_EG = "ar-EG".toLocale()
 
     @Test
     fun `Int_toDayOfWeek() throws an exception when the number is out of range`() {

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

@@ -1,7 +1,7 @@
 package io.islandtime
 
 import io.islandtime.format.TextStyle
-import io.islandtime.locale.localeOf
+import io.islandtime.locale.toLocale
 import io.islandtime.measures.days
 import io.islandtime.measures.months
 import io.islandtime.test.AbstractIslandTimeTest
@@ -78,7 +78,7 @@ class MonthTest : AbstractIslandTimeTest() {
 
     @Test
     fun `localizedName() and displayName() get localized text from the provider`() {
-        @Suppress("LocalVariableName") val en_US = localeOf("en-US")
+        @Suppress("LocalVariableName") val en_US = "en-US".toLocale()
         assertEquals("April", Month.APRIL.localizedName(TextStyle.FULL_STANDALONE, en_US))
         assertEquals("Jun", Month.JUNE.displayName(TextStyle.SHORT_STANDALONE, en_US))
     }

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

@@ -1,7 +1,7 @@
 package io.islandtime
 
 import io.islandtime.format.TimeZoneTextStyle
-import io.islandtime.locale.localeOf
+import io.islandtime.locale.toLocale
 import io.islandtime.measures.hours
 import io.islandtime.test.AbstractIslandTimeTest
 import io.islandtime.zone.TimeZoneRulesException
@@ -91,27 +91,27 @@ class TimeZoneTest : AbstractIslandTimeTest() {
     fun `localizedName() and displayName() get localized text from the provider`() {
         assertEquals(
             "Greenwich Mean Time",
-            TimeZone("Europe/London").localizedName(TimeZoneTextStyle.STANDARD, localeOf("en-GB"))
+            TimeZone("Europe/London").localizedName(TimeZoneTextStyle.STANDARD, "en-GB".toLocale())
         )
         assertEquals(
             "Greenwich Mean Time",
-            TimeZone("Europe/London").displayName(TimeZoneTextStyle.STANDARD, localeOf("en-GB"))
+            TimeZone("Europe/London").displayName(TimeZoneTextStyle.STANDARD, "en-GB".toLocale())
         )
     }
 
     @Test
     fun `displayName() returns the ID on a fixed offset zone`() {
         assertEquals(
             "+01:00",
-            TimeZone("+01:00").displayName(TimeZoneTextStyle.STANDARD, localeOf("en-GB"))
+            TimeZone("+01:00").displayName(TimeZoneTextStyle.STANDARD, "en-GB".toLocale())
         )
     }
 
     @Test
     fun `displayName() returns the ID on an invalid zone`() {
         assertEquals(
             "America/Buffalo",
-            TimeZone("America/Buffalo").displayName(TimeZoneTextStyle.STANDARD, localeOf("en-US"))
+            TimeZone("America/Buffalo").displayName(TimeZoneTextStyle.STANDARD, "en-US".toLocale())
         )
     }
 

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

@@ -1,7 +1,7 @@
 package io.islandtime
 
 import io.islandtime.calendar.WeekSettings.Companion.SUNDAY_START
-import io.islandtime.locale.localeOf
+import io.islandtime.locale.toLocale
 import io.islandtime.test.AbstractIslandTimeTest
 import io.islandtime.test.TestData
 import kotlin.test.Test
@@ -10,7 +10,7 @@ import kotlin.test.assertFailsWith
 
 class WeekDateTest : AbstractIslandTimeTest() {
     @Suppress("PrivatePropertyName")
-    private val en_US = localeOf("en-US")
+    private val en_US = "en-US".toLocale()
 
     @Test
     fun `Date_toWeekDate() converts to ISO week date`() {

core/src/commonTest/kotlin/io/islandtime/format/DateTimeTextProviderTest.kt

@@ -2,15 +2,15 @@ package io.islandtime.format
 
 import io.islandtime.DateTimeException
 import io.islandtime.base.DateTimeField
-import io.islandtime.locale.localeOf
+import io.islandtime.locale.toLocale
 import io.islandtime.test.AbstractIslandTimeTest
 import kotlin.test.*
 
 @Suppress("PrivatePropertyName")
 class DateTimeTextProviderTest : AbstractIslandTimeTest() {
-    private val en_US = localeOf("en-US")
-    private val de_DE = localeOf("de-DE")
-    private val pl_PL = localeOf("pl-PL")
+    private val en_US = "en-US".toLocale()
+    private val de_DE = "de-DE".toLocale()
+    private val pl_PL = "pl-PL".toLocale()
 
     @Test
     fun `textFor() throws an exception when value is out of range`() {

core/src/commonTest/kotlin/io/islandtime/format/NumberStyleTest.kt

@@ -1,16 +1,16 @@
 package io.islandtime.format
 
-import io.islandtime.locale.localeOf
+import io.islandtime.locale.toLocale
 import kotlin.test.Test
 import kotlin.test.assertEquals
 import kotlin.test.assertFailsWith
 import kotlin.test.todo
 
 @Suppress("PrivatePropertyName")
 class NumberStyleTest {
-    private val en_US = localeOf("en-US")
-    private val de_DE = localeOf("de-DE")
-    private val hi_IN_u_nu_native = localeOf("hi-IN-u-nu-native")
+    private val en_US = "en-US".toLocale()
+    private val de_DE = "de-DE".toLocale()
+    private val hi_IN_u_nu_native = "hi-IN-u-nu-native".toLocale()
 
     @Test
     fun `throws an exception when given any empty list`() {

core/src/commonTest/kotlin/io/islandtime/format/TimeZoneTextProviderTest.kt

@@ -1,14 +1,17 @@
 package io.islandtime.format
 
 import io.islandtime.TimeZone
-import io.islandtime.locale.localeOf
+import io.islandtime.locale.toLocale
 import io.islandtime.test.AbstractIslandTimeTest
-import kotlin.test.*
+import kotlin.test.Test
+import kotlin.test.assertEquals
+import kotlin.test.assertFalse
+import kotlin.test.assertNull
 
 @Suppress("PrivatePropertyName")
 class TimeZoneTextProviderTest : AbstractIslandTimeTest() {
-    private val en_US = localeOf("en-US")
-    private val de_DE = localeOf("de-DE")
+    private val en_US = "en-US".toLocale()
+    private val de_DE = "de-DE".toLocale()
 
     @Test
     fun `timeZoneTextFor() returns null when given a fixed offset time zone`() {