Union find exercise - scala dojo 21st of Feb 2013

Connector.scala

package com.bulba.unionfind

trait CityMap {
  def isConnected(from: Point, to: Point): Boolean
}

case class Point(name: String) {
  def - (to: Point) = (this, to)
}

case class London(routes: Map[Point, Set[Point]]) extends CityMap {

  def isConnected(from: Point, to: Point): Boolean = {
    routes.getOrElse(from, Set()) contains to
  }
}


object London {

  def apply(routes: (Point, Point)) = {
    new London(Map(routes._1, Set(routes._2)))
  }

  def apply(routes: List[(Point, Point)]) = {
     // val m: Map[Point, Set[(Point,Point)]] = routes.groupBy(_._1)
     // routes.foldLeft(Map[Point,Set[(Point, Point)]]())((map, (from, to)) => )
    //  val m2: Map[Point, List[Point]] = for (p <- m) p -> p._2.map(_._2)
      new London(routeMap)

  }
}

object CityMapImplicits {
  implicit def stringToPoint(s: String): Point = Point(s)
}

DisjointSetSpec.scala

package com.bulba.unionfind

import org.specs2.mutable.Specification
import com.bulba.unionfind.CityMapImplicits._


class DisjointSetSpec extends Specification {

  "Disjoint set spec" should {

    "read a-b into a graph" in {
      London("a" - "b").isConnected("a","b") must beTrue
    }

    "for a-b b is not connected to a" in {
      London("a" - "b").isConnected("b","a") must beFalse
    }

    "for a-b,b-c a is connected to b and b is connected to c" in {
      val london: Any = London(List("a" - "b", "b" - "c"))
      london.isConnected("a","c") must beTrue
    }
  }
}

Exercise was stopped at the stage of parsing the input data - as the last test states, London should allow a list of connections and rule that with so defined connections a and c would be connected. The apply methods in object London are broken - can you fix them?