Port FoldableSuite to Scala 3

.scalafmt.conf

@@ -1,4 +1,5 @@
-version = "2.7.5"
+version = "3.0.0"
+runner.dialect = "scala3"
 align.preset = none
 maxColumn = 120
 includeNoParensInSelectChains = false

core/src/test/scala-3/cats/derived/FoldableSuite.scala

@@ -0,0 +1,102 @@
+/*
+ * Copyright (c) 2015 Miles Sabin
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package cats
+package derived
+
+import cats.laws.discipline.{FoldableTests, SerializableTests}
+import cats.syntax.all.*
+import org.scalacheck.Arbitrary
+import scala.compiletime.*
+
+class FoldableSuite extends KittensSuite:
+  import FoldableSuite.*
+  import TestDefns.*
+
+  inline def foldableTests[F[_]]: FoldableTests[F] =
+    FoldableTests[F](summonInline)
+
+  inline def testFoldable(inline context: String): Unit =
+    checkAll(s"$context.Foldable[IList]", foldableTests[IList].foldable[Int, Long])
+    checkAll(s"$context.Foldable[Tree]", foldableTests[Tree].foldable[Int, Long])
+    checkAll(s"$context.Foldable[GenericAdt]", foldableTests[GenericAdt].foldable[Int, Long])
+    checkAll(s"$context.Foldable[OptList]", foldableTests[OptList].foldable[Int, Long])
+    checkAll(s"$context.Foldable[ListSnoc]", foldableTests[ListSnoc].foldable[Int, Long])
+    checkAll(s"$context.Foldable[AndChar]", foldableTests[AndChar].foldable[Int, Long])
+    checkAll(s"$context.Foldable[Interleaved]", foldableTests[Interleaved].foldable[Int, Long])
+    checkAll(s"$context.Foldable[BoxNel]", foldableTests[BoxNel].foldable[Int, Long])
+    checkAll(s"$context.Foldable is Serializable", SerializableTests.serializable(summonInline[Foldable[Tree]]))
+
+  locally {
+    import auto.foldable.given
+    testFoldable("auto")
+  }
+
+  locally {
+    import semiInstances.given
+    testFoldable("semiauto")
+  }
+
+end FoldableSuite
+
+object FoldableSuite:
+  import TestDefns.*
+
+  type OptList[A] = Option[List[A]]
+  type ListSnoc[A] = List[Snoc[A]]
+  type AndChar[A] = (A, Char)
+  type BoxNel[A] = Box[Nel[A]]
+
+  object semiInstances:
+    given Foldable[IList] = semiauto.foldable
+    given Foldable[Tree] = semiauto.foldable
+    given Foldable[GenericAdt] = semiauto.foldable
+    given Foldable[OptList] = semiauto.foldable
+    given Foldable[ListSnoc] = semiauto.foldable
+    given Foldable[AndChar] = semiauto.foldable
+    given Foldable[Interleaved] = semiauto.foldable
+    given Foldable[BoxNel] = semiauto.foldable
+
+  final case class Nel[+A](head: A, tail: List[A])
+  object Nel:
+    given [A: Eq]: Eq[Nel[A]] =
+      (x, y) => x.head === y.head && x.tail === y.tail
+
+    given [A: Arbitrary]: Arbitrary[Nel[A]] =
+      Arbitrary(for
+        head <- Arbitrary.arbitrary[A]
+        tail <- Arbitrary.arbitrary[List[A]]
+      yield Nel(head, tail))
+
+    given Foldable[Nel] with
+      def foldLeft[A, B](fa: Nel[A], b: B)(f: (B, A) => B) = fa.tail.foldl(b)(f)
+      def foldRight[A, B](fa: Nel[A], lb: Eval[B])(f: (A, Eval[B]) => Eval[B]) = fa.tail.foldr(lb)(f)
+
+  case class Single[A](value: A) derives Foldable
+
+  enum Many[+A] derives Foldable:
+    case Naught
+    case More(value: A, rest: Many[A])
+
+  enum AtMostOne[+A] derives Foldable:
+    case Naught
+    case Single(value: A)
+
+  enum AtLeastOne[+A] derives Foldable:
+    case Single(value: A)
+    case More(value: A, rest: Option[AtLeastOne[A]])
+
+end FoldableSuite

core/src/test/scala-3/cats/derived/FunctorSuite.scala

@@ -0,0 +1,91 @@
+/*
+ * Copyright (c) 2015 Miles Sabin
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package cats
+package derived
+
+import cats.laws.discipline.*
+import cats.laws.discipline.eq.*
+import scala.compiletime.*
+
+class FunctorSuite extends KittensSuite:
+  import FunctorSuite.*
+  import TestDefns.*
+
+  given ExhaustiveCheck[Predicate[Boolean]] =
+    ExhaustiveCheck.instance(List(_ => true, _ => false, identity, !_))
+
+  inline def functorTests[F[_]]: FunctorTests[F] =
+    FunctorTests[F](summonInline)
+
+  inline def testFunctor(inline context: String): Unit =
+    checkAll(s"$context.Functor[IList]", functorTests[IList].functor[Int, String, Long])
+    checkAll(s"$context.Functor[Tree]", functorTests[Tree].functor[Int, String, Long])
+    checkAll(s"$context.Functor[GenericAdt]", functorTests[GenericAdt].functor[Int, String, Long])
+    checkAll(s"$context.Functor[OptList]", functorTests[OptList].functor[Int, String, Long])
+    checkAll(s"$context.Functor[ListSnoc]", functorTests[ListSnoc].functor[Int, String, Long])
+    // FIXME: Testing `functorTests[AndChar].functor[Int, String, Long]` causes a ClassCastException
+    checkAll(s"$context.Functor[AndChar]", functorTests[AndChar].functor[Int, String, Int])
+    checkAll(s"$context.Functor[Interleaved]", functorTests[Interleaved].functor[Int, String, Long])
+    checkAll(s"$context.Functor[NestedPred]", functorTests[NestedPred].functor[Boolean, Int, Boolean])
+    checkAll(s"$context.Functor is Serializable", SerializableTests.serializable(summonInline[Functor[Tree]]))
+
+  locally {
+    import auto.functor.given
+    testFunctor("auto")
+  }
+
+  locally {
+    import semiInstances.given
+    testFunctor("semiauto")
+  }
+
+end FunctorSuite
+
+object FunctorSuite:
+  import TestDefns.*
+
+  type OptList[A] = Option[List[A]]
+  type ListSnoc[A] = List[Snoc[A]]
+  type AndChar[A] = (A, Char)
+  type Predicate[A] = A => Boolean
+  type NestedPred[A] = Predicate[Predicate[A]]
+
+  object semiInstances:
+    given Functor[IList] = semiauto.functor
+    given Functor[Tree] = semiauto.functor
+    given Functor[GenericAdt] = semiauto.functor
+    given Functor[OptList] = semiauto.functor
+    given Functor[ListSnoc] = semiauto.functor
+    given Functor[AndChar] = semiauto.functor
+    given Functor[Interleaved] = semiauto.functor
+    given Functor[NestedPred] = semiauto.functor
+
+  case class Single[A](value: A) derives Functor
+
+  enum Many[+A] derives Functor:
+    case Naught
+    case More(value: A, rest: Many[A])
+
+  enum AtMostOne[+A] derives Functor:
+    case Naught
+    case Single(value: A)
+
+  enum AtLeastOne[+A] derives Functor:
+    case Single(value: A)
+    case More(value: A, rest: Option[AtLeastOne[A]])
+
+end FunctorSuite