Fix rounding errors in creation of Durations.

Use round instead of manually trying to convert to a Long. Fixes scala/bug#9949 and scala/bug#10320
Jasper-M · May 31, 2017 · 2a2f588 · 2a2f588
1 parent b68cc6c
commit 2a2f588
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diff --git a/src/library/scala/concurrent/duration/Duration.scala b/src/library/scala/concurrent/duration/Duration.scala
@@ -125,7 +125,7 @@ object Duration {
     else if (nanos > Long.MaxValue || nanos < Long.MinValue)
       throw new IllegalArgumentException("trying to construct too large duration with " + nanos + "ns")
     else
-      fromNanos((nanos + 0.5).toLong)
+      fromNanos(nanos.round)
   }
 
   private[this] final val  µs_per_ns = 1000L

diff --git a/test/files/jvm/duration-tck.scala b/test/files/jvm/duration-tck.scala
@@ -202,4 +202,12 @@ object Test extends App {
   ((2 seconds fromNow).timeLeft: FiniteDuration) < 4.seconds mustBe true
   val finite3: FiniteDuration = 3.5 seconds span
 
+  // scala/bug#9949
+  Duration(-1.0, DAYS) mustBe Duration(-1, DAYS)
+  Duration("-10 s").toNanos mustBe -10000000000L
+  Duration(1.0, DAYS) mustBe Duration(1, DAYS)
+  Duration("10 s").toNanos mustBe 10000000000L
+
+  // scala/bug#10320
+  Duration("6803536004516701ns").toNanos mustBe 6803536004516701L
 }