Scala example source code file (TreeTestJVM.scala)

This example Scala source code file (TreeTestJVM.scala) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Scala by Example" ^TM.

Learn more about this Scala project at its project page.

Java - Scala tags/keywords

equal, int, node, speclite, stream, tree, treetestjvm

The TreeTestJVM.scala Scala example source code

package scalaz

import scalaz.scalacheck.ScalazArbitrary._
import Tree._
import org.scalacheck.Gen
import org.scalacheck.Prop.forAll
import std.AllInstances._

object TreeTestJVM extends SpecLite {

  val E = Equal[Tree[Int]]

  "ScalazArbitrary.treeGenSized" ! forAll(Gen.choose(1, 200)){ size =>
    val gen = treeGenSized[Unit](size)
    Stream.continually(gen.sample).flatten.take(10).map(Foldable[Tree].length(_)).forall(_ == size)
  }

  def genTree(size: Int): Tree[Int] =
    (1 to size).foldLeft(Leaf(0))((x, y) => Node(y, Stream(x)))

  val size = 100000

  val deepTree = genTree(size)

  "deep foldMap should not cause a stack overflow" ! {
    deepTree.foldMap(identity) must_== (1 to size).sum
  }

  "deep Tree flatten should not cause a stack overflow" ! {
    deepTree.flatten must_== (size to 0 by -1).toStream
  }

  "deep Equal.equal should not cause a stack overflow" ! {
    E.equal(deepTree, deepTree) must_== true
  }

  "deep Tree toStrictTree should not cause a stack overflow" ! {
    val expectedTree = StrictTreeTestJVM.deepTree
    val actualTree = deepTree.toStrictTree
    StrictTreeTestJVM.E.equal(actualTree, expectedTree) must_== true
  }

  "deep flatMap should not cause a stack overflow" ! {
    E.equal(deepTree.flatMap(Leaf(_)), deepTree) must_== true
  }

}