From a6e85dd543cc21cc36323b25371237eab825751e Mon Sep 17 00:00:00 2001
From: Kailuo Wang <kailuo.wang@gmail.com>
Date: Mon, 23 Oct 2017 13:21:51 -0400
Subject: [PATCH] address feedback / removed duplicated class

---
 .../main/scala/alleycats/std/iterable.scala   | 15 ++--------
 .../src/main/scala/alleycats/std/set.scala    |  2 +-
 .../scala/alleycats/syntax/foldable.scala     |  2 +-
 .../alleycats/tests/AlleycatsSuite.scala      |  2 +-
 .../scala/alleycats/tests/CatsEquality.scala  | 30 -------------------
 5 files changed, 5 insertions(+), 46 deletions(-)
 delete mode 100644 alleycats-tests/src/test/scala/alleycats/tests/CatsEquality.scala

diff --git a/alleycats-core/src/main/scala/alleycats/std/iterable.scala b/alleycats-core/src/main/scala/alleycats/std/iterable.scala
index c58e551d22..7ccde80e75 100644
--- a/alleycats-core/src/main/scala/alleycats/std/iterable.scala
+++ b/alleycats-core/src/main/scala/alleycats/std/iterable.scala
@@ -14,19 +14,8 @@ object IterableInstances {
     new Foldable[Iterable] {
       override def foldLeft[A, B](fa: Iterable[A], b: B)(f: (B, A) => B): B = fa.foldLeft(b)(f)
 
-      // based upon foldRight of List in Cats
-      override def foldRight[A, B](fa: Iterable[A], lb: Eval[B])(f: (A, Eval[B]) => Eval[B]): Eval[B] = {
-        def loop(as: Iterable[A]): Eval[B] =
-          if (as.isEmpty)
-            lb
-          else {
-            val h = as.head
-            val t = as.tail
-            f(h, Eval.defer(loop(t)))
-          }
-        Eval.defer(loop(fa))
-      }
-
+      override def foldRight[A, B](fa: Iterable[A], lb: Eval[B])(f: (A, Eval[B]) => Eval[B]): Eval[B] =
+        Foldable.iterateRight(fa, lb)(f)
     }
 
 }
diff --git a/alleycats-core/src/main/scala/alleycats/std/set.scala b/alleycats-core/src/main/scala/alleycats/std/set.scala
index 8af2432628..da851068e4 100644
--- a/alleycats-core/src/main/scala/alleycats/std/set.scala
+++ b/alleycats-core/src/main/scala/alleycats/std/set.scala
@@ -66,7 +66,7 @@ object SetInstances {
       def foldLeft[A, B](fa: Set[A], b: B)(f: (B, A) => B): B =
         fa.foldLeft(b)(f)
       def foldRight[A, B](fa: Set[A], lb: Eval[B])(f: (A, Eval[B]) => Eval[B]): Eval[B] =
-        Foldable.iterateRight(fa.iterator, lb)(f)
+        Foldable.iterateRight(fa, lb)(f)
       def traverse[G[_]: Applicative, A, B](sa: Set[A])(f: A => G[B]): G[Set[B]] = {
         val G = Applicative[G]
         sa.foldLeft(G.pure(Set.empty[B])) { (buf, a) =>
diff --git a/alleycats-core/src/main/scala/alleycats/syntax/foldable.scala b/alleycats-core/src/main/scala/alleycats/syntax/foldable.scala
index 687209e8a4..ddcbce70b2 100644
--- a/alleycats-core/src/main/scala/alleycats/syntax/foldable.scala
+++ b/alleycats-core/src/main/scala/alleycats/syntax/foldable.scala
@@ -9,6 +9,6 @@ object foldable extends FoldableSyntax
 trait FoldableSyntax {
   implicit class ExtraFoldableOps[F[_]: Foldable, A](fa: F[A]) {
     def foreach(f: A => Unit): Unit =
-      fa.foldLeft(()) { (unit, a) => f(a); unit }
+      fa.foldLeft(()) { (_, a) => f(a) }
   }
 }
diff --git a/alleycats-tests/src/test/scala/alleycats/tests/AlleycatsSuite.scala b/alleycats-tests/src/test/scala/alleycats/tests/AlleycatsSuite.scala
index a558397a7a..9ced1461bc 100644
--- a/alleycats-tests/src/test/scala/alleycats/tests/AlleycatsSuite.scala
+++ b/alleycats-tests/src/test/scala/alleycats/tests/AlleycatsSuite.scala
@@ -7,7 +7,7 @@ import catalysts.Platform
 import cats._
 import cats.instances.AllInstances
 import cats.syntax.{AllSyntax, EqOps}
-
+import cats.tests.StrictCatsEquality
 import org.scalactic.anyvals.{PosZDouble, PosInt, PosZInt}
 import org.scalatest.{FunSuite, Matchers}
 import org.scalatest.prop.{Configuration, GeneratorDrivenPropertyChecks}
diff --git a/alleycats-tests/src/test/scala/alleycats/tests/CatsEquality.scala b/alleycats-tests/src/test/scala/alleycats/tests/CatsEquality.scala
deleted file mode 100644
index f4a9abb2cc..0000000000
--- a/alleycats-tests/src/test/scala/alleycats/tests/CatsEquality.scala
+++ /dev/null
@@ -1,30 +0,0 @@
-package alleycats.tests
-
-import cats._
-
-import org.scalactic._
-import TripleEqualsSupport.AToBEquivalenceConstraint
-import TripleEqualsSupport.BToAEquivalenceConstraint
-
-// The code in this file was taken and only slightly modified from
-// https://github.com/bvenners/equality-integration-demo
-// Thanks for the great examples, Bill!
-
-final class CatsEquivalence[T](T: Eq[T]) extends Equivalence[T] {
-  def areEquivalent(a: T, b: T): Boolean = T.eqv(a, b)
-}
-
-trait LowPriorityStrictCatsConstraints extends TripleEquals {
-  implicit def lowPriorityCatsCanEqual[A, B](implicit B: Eq[B], ev: A <:< B): CanEqual[A, B] =
-    new AToBEquivalenceConstraint[A, B](new CatsEquivalence(B), ev)
-}
-
-trait StrictCatsEquality extends LowPriorityStrictCatsConstraints {
-  override def convertToEqualizer[T](left: T): Equalizer[T] = super.convertToEqualizer[T](left)
-  implicit override def convertToCheckingEqualizer[T](left: T): CheckingEqualizer[T] = new CheckingEqualizer(left)
-  override def unconstrainedEquality[A, B](implicit equalityOfA: Equality[A]): CanEqual[A, B] = super.unconstrainedEquality[A, B]
-  implicit def catsCanEqual[A, B](implicit A: Eq[A], ev: B <:< A): CanEqual[A, B] =
-    new BToAEquivalenceConstraint[A, B](new CatsEquivalence(A), ev)
-}
-
-object StrictCatsEquality extends StrictCatsEquality