Derive Commutative{Semigroup, Monoid} (#341)

core/src/main/scala-3.0.0-RC3/cats/derived/all.scala

@@ -1,13 +1,15 @@
 package cats.derived
 
 object all extends
+  CommutativeMonoidDerivation,
+  CommutativeSemigroupDerivation,
   EmptyDerivation,
-  SemigroupDerivation,
-  MonoidDerivation,
   EqDerivation,
-  PartialOrderDerivation,
-  OrderDerivation,
-  HashDerivation,
-  FunctorDerivation,
   FoldableDerivation,
+  FunctorDerivation,
+  HashDerivation,
+  MonoidDerivation,
+  OrderDerivation,
+  PartialOrderDerivation,
+  SemigroupDerivation,
   TraverseDerivation

core/src/main/scala-3.0.0-RC3/cats/derived/commutativeMonoid.scala

@@ -0,0 +1,14 @@
+package cats.derived
+
+import cats.kernel.CommutativeMonoid
+import shapeless3.deriving.K0
+
+object commutativeMonoid extends CommutativeMonoidDerivation
+
+trait ProductCommutativeMonoid[T[x] <: CommutativeMonoid[x], A](using inst: K0.ProductInstances[T, A])
+    extends ProductCommutativeSemigroup[T, A], ProductMonoid[T, A], CommutativeMonoid[A] {}
+
+trait CommutativeMonoidDerivation:
+  extension (F: CommutativeMonoid.type)
+    inline def derived[A](using gen: K0.ProductGeneric[A]): CommutativeMonoid[A] =
+      new ProductCommutativeMonoid[CommutativeMonoid, A]{}

core/src/main/scala-3.0.0-RC3/cats/derived/commutativeSemigroup.scala

@@ -0,0 +1,14 @@
+package cats.derived
+
+import cats.kernel.CommutativeSemigroup
+import shapeless3.deriving.{K0, Continue}
+
+object commutativeSemigroup extends CommutativeSemigroupDerivation
+
+trait ProductCommutativeSemigroup[T[x] <: CommutativeSemigroup[x], A](using inst: K0.ProductInstances[T, A])
+    extends ProductSemigroup[T, A], CommutativeSemigroup[A] {}
+
+trait CommutativeSemigroupDerivation:
+  extension (F: CommutativeSemigroup.type)
+    inline def derived[A](using gen: K0.ProductGeneric[A]): CommutativeSemigroup[A] =
+      new ProductCommutativeSemigroup[CommutativeSemigroup, A]{}

core/src/main/scala-3.0.0-RC3/cats/derived/monoid.scala

@@ -5,12 +5,12 @@ import shapeless3.deriving.K0
 
 object monoid extends MonoidDerivation
 
-class ProductMonoid[F[x] <: Monoid[x], A](
+trait ProductMonoid[F[x] <: Monoid[x], A](
   using inst: K0.ProductInstances[F, A]
 ) extends ProductSemigroup[F, A], Monoid[A]:
   val empty: A = inst.construct([A] => (F: F[A]) => F.empty)
 
 trait MonoidDerivation:
   extension (M: Monoid.type)
     inline def derived[A](using gen: K0.ProductGeneric[A]): Monoid[A] =
-      ProductMonoid(using K0.mkProductInstances)
+      new ProductMonoid[Monoid, A]{}

core/src/main/scala-3.0.0-RC3/cats/derived/semigroup.scala

@@ -5,7 +5,7 @@ import shapeless3.deriving.K0
 
 object semigroup extends SemigroupDerivation
 
-class ProductSemigroup[F[x] <: Semigroup[x], A](
+trait ProductSemigroup[F[x] <: Semigroup[x], A](
   using inst: K0.ProductInstances[F, A]
 ) extends Semigroup[A]:
   def combine(x: A, y: A): A =
@@ -14,4 +14,4 @@ class ProductSemigroup[F[x] <: Semigroup[x], A](
 trait SemigroupDerivation:
   extension (S: Semigroup.type)
     inline def derived[A](using gen: K0.ProductGeneric[A]): Semigroup[A] =
-      ProductSemigroup(using K0.mkProductInstances)
+      new ProductSemigroup[Semigroup, A]{}

core/src/test/scala-3.0.0-RC3/cats/derived/CommutativeMonoidTests.scala

@@ -0,0 +1,10 @@
+package cats.derived
+
+import alleycats._
+import cats._
+import cats.kernel.CommutativeMonoid
+import cats.derived.all._
+
+class CommutativeMonoidTests { //
+  case class Foo(i: Int, b: Option[Int]) derives CommutativeMonoid
+}

core/src/test/scala-3.0.0-RC3/cats/derived/CommutativeSemigroupTests.scala

@@ -0,0 +1,10 @@
+package cats.derived
+
+import alleycats._
+import cats._
+import cats.kernel.CommutativeSemigroup
+import cats.derived.all._
+
+class CommutativeSemigroupTests { //
+  case class Foo(i: Int, b: Option[Int]) derives CommutativeSemigroup
+}