Merge pull request #4092 from isomarcte/sortedmap-order

typelevel · Jan 21, 2022 · d9616c8 · d9616c8
2 parents 67c5d40 + 3d38c36
commit d9616c8
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Showing 3 changed files with 49 additions and 3 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
@@ -148,6 +148,9 @@ class Tests extends TestsConfig with DisciplineSuite {
   checkAll("PartialOrder[Vector[HasPartialOrder[Int]]]", PartialOrderTests[Vector[HasPartialOrder[Int]]].partialOrder)
   checkAll("PartialOrder[Stream[HasPartialOrder[Int]]]", PartialOrderTests[Stream[HasPartialOrder[Int]]].partialOrder)
   checkAll("PartialOrder[Queue[HasPartialOrder[Int]]]", PartialOrderTests[Queue[HasPartialOrder[Int]]].partialOrder)
+  checkAll("PartialOrder[SortedMap[Int, HasPartialOrder[Int]]]",
+           PartialOrderTests[SortedMap[Int, HasPartialOrder[Int]]].partialOrder
+  )
   checkAll("Semilattice.asMeetPartialOrder[Set[Int]]",
            PartialOrderTests(Semilattice.asMeetPartialOrder[Set[Int]]).partialOrder
   )
@@ -171,6 +174,7 @@ class Tests extends TestsConfig with DisciplineSuite {
   checkAll("Order[Stream[Int]]", OrderTests[Stream[Int]].order)
   checkAll("Order[Queue[Int]]", OrderTests[Queue[Int]].order)
   checkAll("Order[SortedSet[String]", OrderTests[SortedSet[String]].order)
+  checkAll("Order[SortedMap[Int, String]]", OrderTests[SortedMap[Int, String]].order)
   checkAll("fromOrdering[Int]", OrderTests(Order.fromOrdering[Int]).order)
   checkAll("Order.reverse(Order[Int])", OrderTests(Order.reverse(Order[Int])).order)
   checkAll("Order.reverse(Order.reverse(Order[Int]))", OrderTests(Order.reverse(Order.reverse(Order[Int]))).order)

diff --git a/kernel/src/main/scala/cats/kernel/Eq.scala b/kernel/src/main/scala/cats/kernel/Eq.scala
@@ -55,7 +55,7 @@ object Eq
     with EqToEquivConversion
     with ScalaVersionSpecificOrderInstances
     with instances.TupleOrderInstances
-    with OrderInstances0 {
+    with OrderInstances1 {
 
   /**
    * Access an implicit `Eq[A]`.
@@ -224,7 +224,12 @@ private[kernel] trait OrderInstances0 extends PartialOrderInstances {
     cats.kernel.instances.seq.catsKernelStdOrderForSeq[A]
 }
 
-private[kernel] trait PartialOrderInstances extends PartialOrderInstances0 {
+private[kernel] trait OrderInstances1 extends OrderInstances0 {
+  implicit def catsKernelOrderForSortedMap[K, V: Order]: Order[SortedMap[K, V]] =
+    cats.kernel.instances.sortedMap.catsKernelStdOrderForSortedMap[K, V]
+}
+
+private[kernel] trait PartialOrderInstances extends PartialOrderInstances1 {
   implicit def catsKernelPartialOrderForOption[A: PartialOrder]: PartialOrder[Option[A]] =
     cats.kernel.instances.option.catsKernelStdPartialOrderForOption[A]
   implicit def catsKernelPartialOrderForList[A: PartialOrder]: PartialOrder[List[A]] =
@@ -242,6 +247,11 @@ private[kernel] trait PartialOrderInstances0 extends HashInstances {
     cats.kernel.instances.seq.catsKernelStdPartialOrderForSeq[A]
 }
 
+private[kernel] trait PartialOrderInstances1 extends PartialOrderInstances0 {
+  implicit def catsKernelPartialOrderForSortedMap[K, V: PartialOrder]: PartialOrder[SortedMap[K, V]] =
+    cats.kernel.instances.sortedMap.catsKernelStdPartialOrderForSortedMap[K, V]
+}
+
 private[kernel] trait HashInstances extends HashInstances0 {
   implicit def catsKernelHashForSet[A]: Hash[Set[A]] = cats.kernel.instances.set.catsKernelStdHashForSet[A]
   implicit def catsKernelHashForOption[A: Hash]: Hash[Option[A]] =

diff --git a/kernel/src/main/scala/cats/kernel/instances/SortedMapInstances.scala b/kernel/src/main/scala/cats/kernel/instances/SortedMapInstances.scala
@@ -3,7 +3,7 @@ package instances
 
 import scala.collection.immutable.SortedMap
 
-trait SortedMapInstances extends SortedMapInstances2 {
+trait SortedMapInstances extends SortedMapInstances3 {
   implicit def catsKernelStdHashForSortedMap[K: Hash, V: Hash]: Hash[SortedMap[K, V]] =
     new SortedMapHash[K, V]
 
@@ -35,6 +35,38 @@ private[instances] trait SortedMapInstances2 extends SortedMapInstances1 {
 
   implicit def catsKernelStdMonoidForSortedMap[K: Order, V: Semigroup]: Monoid[SortedMap[K, V]] =
     new SortedMapMonoid[K, V]
+
+  implicit def catsKernelStdPartialOrderForSortedMap[K, V: PartialOrder]: PartialOrder[SortedMap[K, V]] =
+    new SortedMapPartialOrder[K, V]
+}
+
+private[instances] trait SortedMapInstances3 extends SortedMapInstances2 {
+  implicit def catsKernelStdOrderForSortedMap[K, V: Order]: Order[SortedMap[K, V]] =
+    new SortedMapOrder[K, V]
+}
+
+private[instances] class SortedMapOrder[K, V](implicit V: Order[V]) extends Order[SortedMap[K, V]] {
+  override def compare(x: SortedMap[K, V], y: SortedMap[K, V]): Int = {
+    implicit val order: Order[K] = Order.fromOrdering(x.ordering)
+    if (x eq y) {
+      0
+    } else {
+      StaticMethods.iteratorCompare(x.iterator, y.iterator)
+    }
+  }
+}
+
+private[instances] class SortedMapPartialOrder[K, V](implicit V: PartialOrder[V])
+    extends PartialOrder[SortedMap[K, V]] {
+  override def partialCompare(x: SortedMap[K, V], y: SortedMap[K, V]): Double = {
+    implicit val order: Order[K] = Order.fromOrdering(x.ordering)
+
+    if (x eq y) {
+      0.0
+    } else {
+      StaticMethods.iteratorPartialCompare(x.iterator, y.iterator)
+    }
+  }
 }
 
 class SortedMapHash[K, V](implicit V: Hash[V], K: Hash[K]) extends SortedMapEq[K, V]()(V) with Hash[SortedMap[K, V]] {