Merge pull request #3423 from saraiva132/add-combinators-to-non-empty…

…-list Add toNev to NonEmptyList variants
typelevel · May 21, 2020 · de8cc76 · de8cc76
2 parents 2bb358d + cf92734
commit de8cc76
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Showing 4 changed files with 43 additions and 1 deletion.
diff --git a/core/src/main/scala-2.13+/cats/data/NonEmptyLazyList.scala b/core/src/main/scala-2.13+/cats/data/NonEmptyLazyList.scala
@@ -445,6 +445,21 @@ class NonEmptyLazyListOps[A](private val value: NonEmptyLazyList[A])
   final def toNes[B >: A](implicit order: Order[B]): NonEmptySet[B] =
     NonEmptySet.of(head, tail: _*)
 
+  /**
+   * Creates new `NonEmptyVector`, similarly to List#toVector from scala standard library.
+   *{{{
+   * scala> import cats.data._
+   * scala> import cats.instances.int._
+   * scala> val nel = NonEmptyLazyList.fromLazyListPrepend(1, LazyList(2,3,4))
+   * scala> val expectedResult = NonEmptyVector.fromVectorUnsafe(Vector(1,2,3,4))
+   * scala> val result = nel.toNev
+   * scala> result === expectedResult
+   * res0: Boolean = true
+   *}}}
+   */
+  final def toNev[B >: A]: NonEmptyVector[B] =
+    NonEmptyVector.fromVectorUnsafe(toLazyList.toVector)
+
   final def show[AA >: A](implicit AA: Show[AA]): String = s"NonEmpty${Show[LazyList[AA]].show(toLazyList)}"
 }
 

diff --git a/core/src/main/scala/cats/data/NonEmptyList.scala b/core/src/main/scala/cats/data/NonEmptyList.scala
@@ -437,6 +437,21 @@ final case class NonEmptyList[+A](head: A, tail: List[A]) extends NonEmptyCollec
    */
   def toNes[B >: A](implicit order: Order[B]): NonEmptySet[B] =
     NonEmptySet.of(head, tail: _*)
+
+  /**
+   * Creates new `NonEmptyVector`, similarly to List#toVector from scala standard library.
+   *{{{
+   * scala> import cats.data._
+   * scala> import cats.instances.int._
+   * scala> val nel = NonEmptyList(1, List(2,3,4))
+   * scala> val expectedResult = NonEmptyVector.fromVectorUnsafe(Vector(1,2,3,4))
+   * scala> val result = nel.toNev
+   * scala> result === expectedResult
+   * res0: Boolean = true
+   *}}}
+   */
+  def toNev[B >: A]: NonEmptyVector[B] =
+    NonEmptyVector.fromVectorUnsafe(toList.toVector)
 }
 
 object NonEmptyList extends NonEmptyListInstances {

diff --git a/tests/src/test/scala-2.13+/cats/tests/NonEmptyLazyListSuite.scala b/tests/src/test/scala-2.13+/cats/tests/NonEmptyLazyListSuite.scala
@@ -1,7 +1,7 @@
 package cats.tests
 
 import cats.{Align, Bimonad, SemigroupK, Show, Traverse}
-import cats.data.{NonEmptyLazyList, NonEmptyLazyListOps}
+import cats.data.{NonEmptyLazyList, NonEmptyLazyListOps, NonEmptyVector}
 import cats.kernel.{Eq, Hash, Order, PartialOrder, Semigroup}
 import cats.kernel.laws.discipline.{EqTests, HashTests, OrderTests, PartialOrderTests, SemigroupTests}
 import cats.laws.discipline.{AlignTests, BimonadTests, NonEmptyTraverseTests, SemigroupKTests, SerializableTests}
@@ -142,6 +142,12 @@ class NonEmptyLazyListSuite extends NonEmptyCollectionSuite[LazyList, NonEmptyLa
       ci.distinct.toList should ===(ci.toList.distinct)
     }
   }
+
+  test("NonEmptyLazyList#toNev is consistent with List#toVector and creating NonEmptyVector from it") {
+    forAll { (ci: NonEmptyLazyList[Int]) =>
+      ci.toNev should ===(NonEmptyVector.fromVectorUnsafe(Vector.empty[Int] ++ ci.toList.toVector))
+    }
+  }
 }
 
 class ReducibleNonEmptyLazyListSuite extends ReducibleSuite[NonEmptyLazyList]("NonEmptyLazyList") {

diff --git a/tests/src/test/scala/cats/tests/NonEmptyListSuite.scala b/tests/src/test/scala/cats/tests/NonEmptyListSuite.scala
@@ -354,6 +354,12 @@ class NonEmptyListSuite extends NonEmptyCollectionSuite[List, NonEmptyList, NonE
       nel.toNes should ===(NonEmptySet.fromSetUnsafe(SortedSet.empty[Int] ++ nel.toList.toSet))
     }
   }
+
+  test("NonEmptyList#toNev is consistent with List#toVector and creating NonEmptyVector from it") {
+    forAll { (nel: NonEmptyList[Int]) =>
+      nel.toNev should ===(NonEmptyVector.fromVectorUnsafe(Vector.empty[Int] ++ nel.toList.toVector))
+    }
+  }
 }
 
 @deprecated("to be able to test deprecated methods", since = "1.0.0-RC1")