From ff9d2744ce9b63321504cb70cf500bb99bc59f75 Mon Sep 17 00:00:00 2001
From: Ilya Gorbunov <ilya.gorbunov@jetbrains.com>
Date: Tue, 18 Jun 2019 05:35:29 +0300
Subject: [PATCH] Provide conversions between Kotlin and Java time durations

---
 .../src/kotlin/time/DurationConversions.kt    | 35 +++++++++
 .../jdk8/test/time/DurationConversionTest.kt  | 72 +++++++++++++++++++
 2 files changed, 107 insertions(+)
 create mode 100644 libraries/stdlib/jdk8/src/kotlin/time/DurationConversions.kt
 create mode 100644 libraries/stdlib/jdk8/test/time/DurationConversionTest.kt

diff --git a/libraries/stdlib/jdk8/src/kotlin/time/DurationConversions.kt b/libraries/stdlib/jdk8/src/kotlin/time/DurationConversions.kt
new file mode 100644
index 00000000000..1de8e33fdbe
--- /dev/null
+++ b/libraries/stdlib/jdk8/src/kotlin/time/DurationConversions.kt
@@ -0,0 +1,35 @@
+/*
+ * 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.
+ */
+
+@file:Suppress("INVISIBLE_MEMBER", "INVISIBLE_REFERENCE")
+@file:JvmName("DurationConversionsJDK8Kt")
+@file:kotlin.jvm.JvmPackageName("kotlin.time.jdk8")
+package kotlin.time
+
+import java.time.*
+
+/**
+ * Converts [java.time.Duration][java.time.Duration] value to [kotlin.time.Duration][Duration] value.
+ *
+ * Durations less than 104 days are converted exactly, and durations greater than that can lose some precision
+ * due to rounding.
+ */
+@SinceKotlin("1.3")
+@ExperimentalTime
+@kotlin.internal.InlineOnly
+public inline fun java.time.Duration.toKotlinDuration(): Duration =
+    this.seconds.seconds + this.nano.nanoseconds
+
+
+/**
+ * Converts [kotlin.time.Duration][Duration] value to value [java.time.Duration][java.time.Duration].
+ *
+ * Durations greater than [Long.MAX_VALUE] seconds are cut to that value.
+ */
+@SinceKotlin("1.3")
+@ExperimentalTime
+@kotlin.internal.InlineOnly
+public inline fun Duration.toJavaDuration(): java.time.Duration =
+    toComponents { seconds, nanoseconds -> java.time.Duration.ofSeconds(seconds, nanoseconds.toLong()) }
\ No newline at end of file
diff --git a/libraries/stdlib/jdk8/test/time/DurationConversionTest.kt b/libraries/stdlib/jdk8/test/time/DurationConversionTest.kt
new file mode 100644
index 00000000000..9cbb31bd3be
--- /dev/null
+++ b/libraries/stdlib/jdk8/test/time/DurationConversionTest.kt
@@ -0,0 +1,72 @@
+/*
+ * 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.
+ */
+
+@file:UseExperimental(ExperimentalTime::class)
+
+package kotlin.jdk8.time.test
+
+import kotlin.random.Random
+import kotlin.test.*
+import kotlin.time.*
+import java.time.Duration as JTDuration
+
+class DurationConversionTest {
+    @Test
+    fun twoWayConversion() {
+        fun test(days: Int, hours: Int, minutes: Int, seconds: Int, millis: Int, nanos: Int) {
+            val duration = days.days + hours.hours + minutes.minutes + seconds.seconds + millis.milliseconds + nanos.nanoseconds
+            val jtDuration = JTDuration.ZERO
+                .plusDays(days.toLong())
+                .plusHours(hours.toLong())
+                .plusMinutes(minutes.toLong())
+                .plusSeconds(seconds.toLong())
+                .plusMillis(millis.toLong())
+                .plusNanos(nanos.toLong())
+
+            assertEquals(jtDuration, duration.toJavaDuration())
+            assertEquals(duration, jtDuration.toKotlinDuration())
+        }
+
+        repeat(100) {
+            test(
+                days = Random.nextInt(-100, 100),
+                hours = Random.nextInt(-48, 48),
+                minutes = Random.nextInt(-600, 600),
+                seconds = Random.nextInt(-600, 600),
+                millis = Random.nextInt(-1000000, 1000000),
+                nanos = Random.nextInt()
+            )
+        }
+    }
+
+    @Test
+    fun javaToKotlinRounding() {
+        val jtDuration = JTDuration.ofDays(105).plusNanos(1)
+        val duration = jtDuration.toKotlinDuration()
+        assertEquals(105.days, duration)
+    }
+
+    @Test
+    fun kotlinToJavaClamping() {
+        val duration = Long.MAX_VALUE.seconds * 5
+        val jtDuration = duration.toJavaDuration()
+        assertEquals(JTDuration.ofSeconds(Long.MAX_VALUE), jtDuration)
+
+        val jtnegDuration = (-duration).toJavaDuration()
+        assertEquals(JTDuration.ofSeconds(Long.MIN_VALUE), jtnegDuration)
+    }
+
+    @Test
+    fun randomIsoConversionEquivalence() {
+        repeat(100) {
+            val duration = Random.nextLong(-(1 shl 53) + 1, 1 shl 53).nanoseconds
+            val fromString = JTDuration.parse(duration.toIsoString())
+            val fromDuration = duration.toJavaDuration()
+
+            assertEquals(fromString, fromDuration)
+        }
+    }
+}
+