Implement DurationUnit in JS, add doc summary and conversion test

libraries/stdlib/js/src/kotlin/time/DurationUnit.kt

@@ -1,37 +1,48 @@
 /*
- * Copyright 2010-2019 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
+ * Copyright 2010-2019 JetBrains s.r.o. and Kotlin Programming Language contributors.
- * that can be found in the license/LICENSE.txt file.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
  */
 
 package kotlin.time
 
-public actual enum class DurationUnit {
+
+public actual enum class DurationUnit(internal val scale: Double) {
     /**
      * Time unit representing one nanosecond, which is 1/1000 of a microsecond.
      */
-    NANOSECONDS,
+    NANOSECONDS(1e0),
     /**
      * Time unit representing one microsecond, which is 1/1000 of a millisecond.
      */
-    MICROSECONDS,
+    MICROSECONDS(1e3),
     /**
      * Time unit representing one millisecond, which is 1/1000 of a second.
      */
-    MILLISECONDS,
+    MILLISECONDS(1e6),
     /**
      * Time unit representing one second.
      */
-    SECONDS,
+    SECONDS(1e9),
     /**
      * Time unit representing one minute.
      */
-    MINUTES,
+    MINUTES(60e9),
     /**
      * Time unit representing one hour.
      */
-    HOURS,
+    HOURS(3600e9),
     /**
-     * Time unit representing one day, which always equals 24 hours.
+     * Time unit representing one day, which is always equal to 24 hours.
      */
-    DAYS;
+    DAYS(86400e9);
 }
+
+public actual fun convertDurationUnit(value: Double, sourceUnit: DurationUnit, targetUnit: DurationUnit): Double {
+    val sourceCompareTarget = sourceUnit.scale.compareTo(targetUnit.scale)
+    return when {
+        sourceCompareTarget > 0 -> value * (sourceUnit.scale / targetUnit.scale)
+        sourceCompareTarget < 0 -> value / (targetUnit.scale / sourceUnit.scale)
+        else -> value
+    }
+}
+

libraries/stdlib/js/src/kotlin/time/conversions.kt

@@ -1,10 +0,0 @@
-/*
- * Copyright 2010-2019 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
- * that can be found in the license/LICENSE.txt file.
- */
-
-package kotlin.time
-
-public actual fun convertDurationUnit(value: Double, sourceUnit: DurationUnit, targetUnit: DurationUnit): Double {
-    TODO("not implemented")
-}

libraries/stdlib/jvm/src/kotlin/time/DurationUnitJvm.kt

@@ -1,6 +1,6 @@
 /*
- * Copyright 2010-2019 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
+ * Copyright 2010-2019 JetBrains s.r.o. and Kotlin Programming Language contributors.
- * that can be found in the license/LICENSE.txt file.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
  */
 
 @file:kotlin.jvm.JvmMultifileClass()
@@ -8,14 +8,8 @@
 
 package kotlin.time
 
-//Actual typealias 'DurationUnit' has no corresponding expected declaration
-//The following declaration is incompatible because modality is different:
-//    public final expect enum class DurationUnit : Enum<DurationUnit>
-
-@Suppress("ACTUAL_WITHOUT_EXPECT")
 public actual typealias DurationUnit = java.util.concurrent.TimeUnit
 
-
 public actual fun convertDurationUnit(value: Double, sourceUnit: DurationUnit, targetUnit: DurationUnit): Double {
     val sourceInTargets = targetUnit.convert(1, sourceUnit)
     if (sourceInTargets > 0)

libraries/stdlib/src/kotlin/time/DurationUnit.kt

@@ -1,6 +1,6 @@
 /*
- * Copyright 2010-2019 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
+ * Copyright 2010-2019 JetBrains s.r.o. and Kotlin Programming Language contributors.
- * that can be found in the license/LICENSE.txt file.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
  */
 
 @file:kotlin.jvm.JvmMultifileClass()
@@ -9,6 +9,11 @@
 package kotlin.time
 
 
+/**
+ * The list of possible time measurement units, in which a duration can be expressed.
+ *
+ * The smallest time unit is [NANOSECONDS] and the largest is [DAYS], which corresponds to exactly 24 [HOURS].
+ */
 public expect enum class DurationUnit {
     /**
      * Time unit representing one nanosecond, which is 1/1000 of a microsecond.
@@ -35,12 +40,12 @@ public expect enum class DurationUnit {
      */
     HOURS,
     /**
-     * Time unit representing one day, which always equals 24 hours.
+     * Time unit representing one day, which is always equal to 24 hours.
      */
     DAYS;
 }
 
-
+/** Converts the given time duration [value] expressed in the specified [sourceUnit] into the specified [targetUnit]. */
 public expect fun convertDurationUnit(value: Double, sourceUnit: DurationUnit, targetUnit: DurationUnit): Double
 
 

libraries/stdlib/test/time/DurationUnitTest.kt

@@ -0,0 +1,46 @@
+/*
+ * Copyright 2010-2019 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package test.time
+
+import kotlin.test.*
+import kotlin.time.*
+// TODO: Use star import after KT-30983 is fixed
+import kotlin.time.DurationUnit.DAYS
+import kotlin.time.DurationUnit.HOURS
+import kotlin.time.DurationUnit.MINUTES
+import kotlin.time.DurationUnit.SECONDS
+import kotlin.time.DurationUnit.MILLISECONDS
+import kotlin.time.DurationUnit.MICROSECONDS
+import kotlin.time.DurationUnit.NANOSECONDS
+
+class DurationUnitTest {
+
+    @Test
+    fun conversion() {
+        fun test(sourceValue: Double, sourceUnit: DurationUnit, targetValue: Double, targetUnit: DurationUnit) {
+            assertEquals(
+                targetValue, convertDurationUnit(sourceValue, sourceUnit, targetUnit),
+                "Expected $sourceValue $sourceUnit to be $targetValue $targetUnit"
+            )
+            assertEquals(
+                sourceValue, convertDurationUnit(targetValue, targetUnit, sourceUnit),
+                "Expected $targetValue $targetUnit to be $sourceValue $sourceUnit"
+            )
+        }
+        test(1.0, MINUTES, 60.0, SECONDS)
+        test(30.0, MINUTES, 0.5, HOURS)
+        test(12.0, HOURS, 0.5, DAYS)
+        test(720.0, MINUTES, 0.5, DAYS)
+        test(1.0, DAYS, 86400.0, SECONDS)
+        test(1.0, DAYS, 86400e9, NANOSECONDS)
+        test(50.0, NANOSECONDS, 0.05, MICROSECONDS)
+        test(50.0, NANOSECONDS, 50e-9, SECONDS)
+        test(16.0, MILLISECONDS, 0.016, SECONDS)
+    }
+
+
+
+}