ScalaTest case for findCycleContaining

findContainingTest.scala

import Mario._

import org.scalatest.FlatSpec

import scalax.collection.Graph
import scalax.collection.GraphEdge.UnDiEdge // shortcuts
import scalax.collection.GraphPredef._

class findContainingTest extends FlatSpec {

  def checkLength[T](found: Option[Traversable[T]], sizes: List[Int]): Boolean = found match {
    case Some(vector) if sizes.contains(vector.size) ⇒ true
    case _ ⇒ false
  }

  val g: Graph[Int,UnDiEdge] = Graph(4~5, 5~6, 6~7, 7~5, 7~8, 8~4)

  "The proposed undirected graph" must "have some cycle containing node 4" in {
    assert(checkLength(g.findCycleContaining(4), List(5, 6)) === true)
  }

  it must "have some cycle containing node 5" in {
    assert(checkLength(g.findCycleContaining(5), List(4, 5, 6)) === true)
  }

  it must "have some cycle containing node 6" in {
    assert(checkLength(g.findCycleContaining(6), List(4, 6)) === true)
  }

  "The proposed undirected graph without edge 5~7" must "have just one cycle containing each node" in {
    assert(checkLength((g - 5~7).findCycleContaining(4), List(6)) === true)
    assert(checkLength((g - 5~7).findCycleContaining(5), List(6)) === true)
    assert(checkLength((g - 5~7).findCycleContaining(6), List(6)) === true)
  }

  "The proposed undirected graph without edge 6~7" must "have just one cycle containing node 4 and 5" in {
    assert(checkLength((g - 6~7).findCycleContaining(4), List(5)) === true)
    assert(checkLength((g - 6~7).findCycleContaining(5), List(5)) === true)
  }

  it must "NOT have a cycle containing node 6" in {
    assert((g - 6~7).findCycleContaining(6).isEmpty === true)
  }

  "The proposed undirected graph without edge 4~8" must "NOT have a cycle containing node 4" in {
    assert((g - 4~8).findCycleContaining(4).isEmpty === true)
  }

  it must "have just one cycle containing node 5 and 6" in {
    assert(checkLength((g - 4~8).findCycleContaining(5), List(4)) === true)
    assert(checkLength((g - 4~8).findCycleContaining(6), List(4)) === true)
  }

}