Added assertions for tree consistency

1 files changed, 4 insertions, 0 deletions

diff --git a/src/library/scala/collection/immutable/HashMap.scala b/src/library/scala/collection/immutable/HashMap.scala
index b8b9f9973e..8ecad063f2 100644
--- a/src/library/scala/collection/immutable/HashMap.scala
+++ b/src/library/scala/collection/immutable/HashMap.scala
@@ -230,6 +230,7 @@ object HashMap extends ImmutableMapFactory[HashMap] with BitOperations.Int {
 
   private[collection] class HashMapCollision1[A, +B](private[collection] val hash: Int, val kvs: ListMap[A, B @uV])
           extends HashMap[A, B @uV] {
+    assert(kvs.size > 1)
 
     override def size = kvs.size
 
@@ -278,6 +279,9 @@ object HashMap extends ImmutableMapFactory[HashMap] with BitOperations.Int {
     private[collection] val size0: Int
   ) extends HashMap[A, B @uV] {
 
+    assert(Integer.bitCount(bitmap) == elems.length)
+    assert(elems.length > 1 || (elems.length == 1 && elems(0).isInstanceOf[HashTrieMap[_,_]]))
+
 /*
     def this (level: Int, m1: HashMap1[A,B], m2: HashMap1[A,B]) = {
       this(((m1.hash >>> level) & 0x1f) | ((m2.hash >>> level) & 0x1f), {