added another list example

Author: hellrich

src/main/scala/stdlib/PatternMatching.scala

@@ -189,11 +189,22 @@ object PatternMatching extends FlatSpec with Matchers with org.scalaexercises.de
     */
   def againstListsIVPatternMatching(res0: Int) {
     val r = List(1, 2, 3) match {
-      case x :: y :: Nil ⇒ y
+      case x :: y :: Nil ⇒ y // only matches a list with exactly two items
       case _             ⇒ 0
     }
 
     r should be(res0)
   }
 
+  /** If a pattern is exactly one element longer than a `List`, it extracts the final `Nil`:
+    */
+  def againstListsVPatternMatching(res0: Boolean) {
+    val r = List(1, 2, 3) match {
+      case x :: y :: z :: tail ⇒ tail
+      case _             ⇒ 0
+    }
+
+    r == Nil should be(res0)
+  }
+
 }

src/test/scala/stdlib/PatternMatchingSpec.scala

@@ -105,4 +105,14 @@ class PatternMatchingSpec extends Spec with Checkers {
       )
     )
   }
+
+  def `pattern matching lists part five` = {
+    check(
+      Test.testSuccess(
+        PatternMatching.againstListsVPatternMatching _,
+        true :: HNil
+      )
+    )
+  }
+
 }