From 8c730e180ce18f4a161517b6543f78322b27ce48 Mon Sep 17 00:00:00 2001
From: Ilya Gorbunov <ilya.gorbunov@jetbrains.com>
Date: Mon, 3 Jun 2019 18:36:06 +0300
Subject: [PATCH] Make ClockMark an abstract class instead of an interface

---
 libraries/stdlib/js/src/kotlin/time/MonoClock.kt |  2 +-
 libraries/stdlib/src/kotlin/time/Clock.kt        | 10 +++++-----
 libraries/stdlib/src/kotlin/time/Clocks.kt       |  4 ++--
 3 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/libraries/stdlib/js/src/kotlin/time/MonoClock.kt b/libraries/stdlib/js/src/kotlin/time/MonoClock.kt
index 99d1ea9f4c7..90bb837b3e5 100644
--- a/libraries/stdlib/js/src/kotlin/time/MonoClock.kt
+++ b/libraries/stdlib/js/src/kotlin/time/MonoClock.kt
@@ -30,7 +30,7 @@ internal external interface Process {
 
 internal class HrTimeClock(val process: Process) : Clock {
 
-    override fun mark(): ClockMark = object : ClockMark {
+    override fun mark(): ClockMark = object : ClockMark() {
         val startedAt = process.hrtime()
         override fun elapsed(): Duration =
             process.hrtime(startedAt).let { (seconds, nanos) -> seconds.seconds + nanos.nanoseconds }
diff --git a/libraries/stdlib/src/kotlin/time/Clock.kt b/libraries/stdlib/src/kotlin/time/Clock.kt
index 328858b93cd..1a00e8f6fbd 100644
--- a/libraries/stdlib/src/kotlin/time/Clock.kt
+++ b/libraries/stdlib/src/kotlin/time/Clock.kt
@@ -24,29 +24,29 @@ public interface Clock {
  * Represents a time point notched on a particular [Clock]. Remains bound to the clock it was taken from
  * and allows querying for the duration of time elapsed from that point (see the function [elapsed]).
  */
-public interface ClockMark {
+public abstract class ClockMark {
     /**
      * Returns the amount of time passed from this clock mark on the clock from which this mark was taken.
      */
-    fun elapsed(): Duration
+    abstract fun elapsed(): Duration
 
     /**
      * Returns a clock mark on the same clock that is ahead of this clock mark by the specified [duration].
      *
      * The returned clock mark is more _late_ when the [duration] is positive, and more _early_ when the [duration] is negative.
      */
-    operator fun plus(duration: Duration): ClockMark = AdjustedClockMark(this, duration)
+    open operator fun plus(duration: Duration): ClockMark = AdjustedClockMark(this, duration)
 
     /**
      * Returns a clock mark on the same clock that is behind this clock mark by the specified [duration].
      *
      * The returned clock mark is more _early_ when the [duration] is positive, and more _late_ when the [duration] is negative.
      */
-    operator fun minus(duration: Duration): ClockMark = plus(-duration)
+    open operator fun minus(duration: Duration): ClockMark = plus(-duration)
 }
 
 
-private class AdjustedClockMark(val mark: ClockMark, val adjustment: Duration) : ClockMark {
+private class AdjustedClockMark(val mark: ClockMark, val adjustment: Duration) : ClockMark() {
     override fun elapsed(): Duration = mark.elapsed() - adjustment
 
     override fun plus(duration: Duration): ClockMark = AdjustedClockMark(mark, adjustment + duration)
diff --git a/libraries/stdlib/src/kotlin/time/Clocks.kt b/libraries/stdlib/src/kotlin/time/Clocks.kt
index 5657f8a78a3..92446213ba7 100644
--- a/libraries/stdlib/src/kotlin/time/Clocks.kt
+++ b/libraries/stdlib/src/kotlin/time/Clocks.kt
@@ -18,7 +18,7 @@ public expect object MonoClock : Clock
 public abstract class AbstractLongClock(protected val unit: DurationUnit) : Clock {
     protected abstract fun read(): Long
 
-    override fun mark(): ClockMark = object : ClockMark {
+    override fun mark(): ClockMark = object : ClockMark() {
         val startedAt = read()
         override fun elapsed(): Duration = (read() - startedAt).toDuration(this@AbstractLongClock.unit)
     }
@@ -30,7 +30,7 @@ public abstract class AbstractLongClock(protected val unit: DurationUnit) : Cloc
 public abstract class AbstractDoubleClock(protected val unit: DurationUnit) : Clock {
     protected abstract fun read(): Double
 
-    override fun mark(): ClockMark = object : ClockMark {
+    override fun mark(): ClockMark = object : ClockMark() {
         val startedAt = read()
         override fun elapsed(): Duration = (read() - startedAt).toDuration(this@AbstractDoubleClock.unit)
     }