Add Reusability instances for Set{Interval,Timeout}*

Closes #740

Author: japgolly

core/src/main/scala/japgolly/scalajs/react/Reusability.scala

@@ -8,6 +8,7 @@ import scala.annotation.tailrec
 import scala.concurrent.{duration => scd}
 import scala.reflect.ClassTag
 import scala.scalajs.LinkingInfo.productionMode
+import scala.scalajs.js.timers.{SetIntervalHandle, SetTimeoutHandle}
 import scala.scalajs.js.{Date => JsDate}
 
 /**
@@ -315,6 +316,18 @@ object Reusability extends ScalaVersionSpecificReusability {
   implicit def box[A: Reusability]: Reusability[Box[A]] =
     by(_.unbox)
 
+  implicit lazy val setIntervalHandle: Reusability[SetIntervalHandle] =
+    by_==
+
+  implicit lazy val setTimeoutHandle: Reusability[SetTimeoutHandle] =
+    by_==
+
+  implicit lazy val callbackSetIntervalResult: Reusability[Callback.SetIntervalResult] =
+    byRef || by(_.handle)
+
+  implicit lazy val callbackSetTimeoutResult: Reusability[Callback.SetTimeoutResult] =
+    byRef || by(_.handle)
+
   // java.time._
 
   implicit def clock: Reusability[Clock] =

doc/changelog/1.7.3.md

@@ -0,0 +1,7 @@
+# 1.7.3
+
+* Add implicit `Reusability` instances for:
+  * `SetIntervalHandle`
+  * `SetTimeoutHandle`
+  * `Callback.SetIntervalResult`
+  * `Callback.SetTimeoutResult`