Arbitrary instances for NonEmpty Lists and Vectors

modules/scalacheck/shared/src/main/scala/eu/timepit/refined/scalacheck/all.scala

@@ -8,3 +8,4 @@ object all
     with RefTypeInstances
     with StringInstances
     with CollectionInstances
+    with CollectionInstancesBinCompat1

modules/scalacheck/shared/src/main/scala/eu/timepit/refined/scalacheck/collection.scala

@@ -1,12 +1,12 @@
 package eu.timepit.refined.scalacheck
 
 import eu.timepit.refined.api.{Refined, RefType}
-import eu.timepit.refined.collection.Size
+import eu.timepit.refined.collection.{NonEmpty, Size}
 import org.scalacheck.{Arbitrary, Gen}
 import org.scalacheck.util.Buildable
 
 /** Module that provides `Arbitrary` instances for collection predicates. */
-object collection extends CollectionInstances
+object collection extends CollectionInstances with CollectionInstancesBinCompat1
 
 trait CollectionInstances {
 
@@ -36,3 +36,22 @@ trait CollectionInstances {
       Gen.buildableOfN[C, T](n.value, arbT.arbitrary)
     })
 }
+
+trait CollectionInstancesBinCompat1 {
+
+  implicit def listNonEmptyArbitrary[F[_, _]: RefType, T: Arbitrary]
+    : Arbitrary[F[List[T], NonEmpty]] =
+    buildableNonEmptyArbitrary[F, List[T], T]
+
+  implicit def vectorNonEmptyArbitrary[F[_, _]: RefType, T: Arbitrary]
+    : Arbitrary[F[Vector[T], NonEmpty]] =
+    buildableNonEmptyArbitrary[F, Vector[T], T]
+
+  private[scalacheck] def buildableNonEmptyArbitrary[F[_, _]: RefType, C, T](
+      implicit
+      arbT: Arbitrary[T],
+      ev1: Buildable[T, C],
+      ev2: C => Traversable[T]
+  ): Arbitrary[F[C, NonEmpty]] =
+    arbitraryRefType(Gen.nonEmptyBuildableOf(arbT.arbitrary))
+}

modules/scalacheck/shared/src/main/scala/eu/timepit/refined/scalacheck/string.scala

@@ -28,13 +28,8 @@ trait StringInstances {
 
   implicit def nonEmptyStringArbitrary[F[_, _]](
       implicit rt: RefType[F]
-  ): Arbitrary[F[String, NonEmpty]] = {
-    val nonEmptyStringGen = for {
-      s <- Arbitrary.arbString.arbitrary
-      c <- Arbitrary.arbChar.arbitrary
-    } yield s + c.toString
-    arbitraryRefType(nonEmptyStringGen)
-  }
+  ): Arbitrary[F[String, NonEmpty]] =
+    collection.buildableNonEmptyArbitrary[F, String, Char]
 
   implicit def stringSizeArbitrary[F[_, _]: RefType, P](
       implicit

modules/scalacheck/shared/src/test/scala/eu/timepit/refined/scalacheck/CollectionArbitrarySpec.scala

@@ -2,7 +2,7 @@ package eu.timepit.refined.scalacheck
 
 import eu.timepit.refined.W
 import eu.timepit.refined.api.Refined
-import eu.timepit.refined.collection.{MaxSize, Size}
+import eu.timepit.refined.collection.{MaxSize, NonEmpty, Size}
 import eu.timepit.refined.numeric.Interval
 import eu.timepit.refined.scalacheck.collection._
 import eu.timepit.refined.scalacheck.numeric._
@@ -17,9 +17,14 @@ class CollectionArbitrarySpec extends Properties("CollectionArbitrary") {
   property("List[String] Refined MaxSize[_13]") =
     checkArbitraryRefinedType[List[String] Refined MaxSize[_13]]
 
+  property("List[Int] Refined NonEmpty") = checkArbitraryRefinedType[List[Int] Refined NonEmpty]
+
   property("Vector[Int] Refined MaxSize[23]") =
     checkArbitraryRefinedType[Vector[Int] Refined MaxSize[W.`23`.T]]
 
+  property("Vector[Double] Refined NonEmpty") =
+    checkArbitraryRefinedType[Vector[Double] Refined NonEmpty]
+
   property("Size[Interval.Closed[23, 42]]") =
     checkArbitraryRefinedType[List[Char] Refined Size[Interval.Closed[W.`23`.T, W.`42`.T]]]
 }

notes/0.9.1.markdown

@@ -0,0 +1,8 @@
+### New features
+
+* Add `Arbitrary` instances for `NonEmpty` `List`s and `Vector`s.
+  ([#486][#486] by [@fthomas][@fthomas])
+
+[#486]: https://github.com/fthomas/refined/pull/486
+
+[@fthomas]: https://github.com/fthomas