From 5b12748875d6ba225e6f6371b159b82a09c7814a Mon Sep 17 00:00:00 2001
From: Tim Nielens <tim.nielens@restore.energy>
Date: Sun, 28 Feb 2021 22:57:46 +0100
Subject: [PATCH] remove unnecessary Duration scalacheck instances

---
 .../scala/cats/kernel/laws/LawTests.scala     | 32 +++----------------
 1 file changed, 4 insertions(+), 28 deletions(-)

diff --git a/kernel-laws/shared/src/test/scala/cats/kernel/laws/LawTests.scala b/kernel-laws/shared/src/test/scala/cats/kernel/laws/LawTests.scala
index e7d2979eb0..fc469d53d3 100644
--- a/kernel-laws/shared/src/test/scala/cats/kernel/laws/LawTests.scala
+++ b/kernel-laws/shared/src/test/scala/cats/kernel/laws/LawTests.scala
@@ -30,23 +30,6 @@ object KernelCheck {
   implicit val arbitraryUUID: Arbitrary[UUID] =
     Arbitrary(Gen.uuid)
 
-  implicit val arbitraryDuration: Arbitrary[Duration] = {
-    // max range is +/- 292 years, but we give ourselves some extra headroom
-    // to ensure that we can add these things up. they crash on overflow.
-    val n = (292L * 365) / 500
-    Arbitrary(
-      Gen.oneOf(
-        Gen.choose(-n, n).map(Duration(_, DAYS)),
-        Gen.choose(-n * 24L, n * 24L).map(Duration(_, HOURS)),
-        Gen.choose(-n * 1440L, n * 1440L).map(Duration(_, MINUTES)),
-        Gen.choose(-n * 86400L, n * 86400L).map(Duration(_, SECONDS)),
-        Gen.choose(-n * 86400000L, n * 86400000L).map(Duration(_, MILLISECONDS)),
-        Gen.choose(-n * 86400000000L, n * 86400000000L).map(Duration(_, MICROSECONDS)),
-        Gen.choose(-n * 86400000000000L, n * 86400000000000L).map(Duration(_, NANOSECONDS))
-      )
-    )
-  }
-
   implicit val arbitraryFiniteDuration: Arbitrary[FiniteDuration] = {
     // max range is +/- 292 years, but we give ourselves some extra headroom
     // to ensure that we can add these things up. they crash on overflow.
@@ -64,6 +47,10 @@ object KernelCheck {
     )
   }
 
+  // `Duration.Undefined`, `Duration.Inf` and `Duration.MinusInf` break the tests
+  implicit val arbitraryDuration: Arbitrary[Duration] =
+    Arbitrary(arbitraryFiniteDuration.arbitrary.map(fd => fd: Duration))
+
   // Copied from cats-laws.
   implicit def arbitrarySortedMap[K: Arbitrary: Order, V: Arbitrary]: Arbitrary[SortedMap[K, V]] =
     Arbitrary(arbitrary[Map[K, V]].map(s => SortedMap.empty[K, V](implicitly[Order[K]].toOrdering) ++ s))
@@ -101,17 +88,6 @@ object KernelCheck {
 
   implicit val cogenUUID: Cogen[UUID] =
     Cogen[(Long, Long)].contramap(u => (u.getMostSignificantBits, u.getLeastSignificantBits))
-
-  implicit val cogenDuration: Cogen[Duration] =
-    Cogen[Long].contramap { d =>
-      if (d == Duration.Inf) 3896691548866406746L
-      else if (d == Duration.MinusInf) 1844151880988859955L
-      else if (d == Duration.Undefined) -7917359255778781894L
-      else d.toNanos
-    }
-
-  implicit val cogenFiniteDuration: Cogen[FiniteDuration] =
-    Cogen[Long].contramap(_.toNanos)
 }
 
 class TestsConfig extends ScalaCheckSuite {