package git

//case class PullRequest(branch: String, base:String, account:String, repo:String)
case class PullRequest(number: Int, branch: String, base:String) {
  override def toString(): String = {
    s"#$number: '$branch'"
  }
}

object PullRequest {

  def getPairs(pulls: List[PullRequest]): Set[(PullRequest, PullRequest)] = {
    val pairs = for {
      // Pairwise
      x <- pulls
      y <- pulls
      // Normalize
      if x.number != y.number
      pr1 = if (x.number < y.number) x else y
      pr2 = if (x.number < y.number) y else x
    } yield (pr1, pr2)
    // Distinct
    pairs.toSet
  }
}

package git

//case class PullRequest(branch: String, base:String, account:String, repo:String)
case class PullRequest(number: Int, branch: String, base:String) {
  override def toString(): String = {
    s"#$number: '$branch'"
  }
}

object PullRequest {

  def getPairs(pulls: List[PullRequest]): Traversable[(PullRequest, PullRequest)] = {
    val pairs = for {
      // Pairwise
      x <- pulls
      y <- pulls
      // Normalize
      if x.number != y.number
      pr1 = if (x.number < y.number) x else y
      pr2 = if (x.number < y.number) y else x
    } yield (pr1, pr2)
    // Distinct
    pairs.toSet
  }
}

--- 
+++ 
@@ -9,7 +9,7 @@
 
 object PullRequest {
 
-  def getPairs(pulls: List[PullRequest]): Traversable[(PullRequest, PullRequest)] = {
+  def getPairs(pulls: List[PullRequest]): Set[(PullRequest, PullRequest)] = {
     val pairs = for {
       // Pairwise
       x <- pulls
Return set of pairs instead of traversable
