implement review

Author: fdietze

compat/src/main/scala-2.11_2.12/scala/collection/compat/PackageShared.scala

@@ -57,11 +57,7 @@ private[compat] trait PackageShared {
 
   implicit def genericOrderedCompanionToCBF[A, CC[X] <: Traversable[X]](
       fact: GenericOrderedCompanion[CC])(implicit ordering: Ordering[A]): CanBuildFrom[Any, A, CC[A]] = {
-    val builder: m.Builder[A, CC[A]] = fact match {
-      case m.PriorityQueue => new IdentityPreservingBuilder[A, m.PriorityQueue](m.PriorityQueue.newBuilder[A])
-      case _ => fact.newBuilder[A]
-    }
-    simpleCBF(builder)
+    simpleCBF(fact.newBuilder[A])
   }
 
   implicit def sortedSetCompanionToCBF[A: Ordering,

compat/src/test/scala/scala/jdk/CollectionConvertersTest.scala

@@ -85,11 +85,6 @@ class CollectionConvertersTest {
       assert((s: m.Map[String, String]) == p) // not eq
     }
 
-    {
-      val t: m.PriorityQueue[String] = it.to(m.PriorityQueue)
-      assert((t: m.PriorityQueue[String]) eq t) // what should we test here?
-    }
-
 //    Scala.js doesn't like the concurrent packages
 //    {
 //      val p: scala.collection.concurrent.Map[String, String] = scala.collection.concurrent.TrieMap(it.map(a => (a, a)).toSeq: _*)

compat/src/test/scala/test/scala/collection/CollectionTest.scala

@@ -17,6 +17,7 @@ import org.junit.Test
 
 import scala.collection.compat._
 import scala.collection.immutable.BitSet
+import scala.collection.mutable.PriorityQueue
 import scala.collection.LinearSeq
 
 class CollectionTest {
@@ -35,6 +36,10 @@ class CollectionTest {
     val bT: BitSet = b
     assertEquals(BitSet(1, 2, 3), b)
 
+    val c          = xs.to(PriorityQueue) // we can fake a type constructor for the 2 standard BitSet types
+    val cT: PriorityQueue[Int]  = c
+    assert(PriorityQueue(1, 2, 3) sameElements c)
+
     val ys = List(1 -> "a", 2 -> "b")
     val m  = ys.to(Map)
     // Not possible - `to` returns a Col[A] so this is only typed as an Iterable[(Int, String)]