SI-10164 BitSet.tail zigs where it zagged

A cut/paste issue, an increment was held over from head,
which scans forward, to tail, which scans backward.

1 files changed, 9 insertions, 3 deletions

diff --git a/test/junit/scala/collection/mutable/BitSetTest.scala b/test/junit/scala/collection/mutable/BitSetTest.scala
index 84b906e8d5..f0a0ef5d75 100644
--- a/test/junit/scala/collection/mutable/BitSetTest.scala
+++ b/test/junit/scala/collection/mutable/BitSetTest.scala
@@ -7,7 +7,7 @@ import org.junit.runners.JUnit4
 @RunWith(classOf[JUnit4])
 class BitSetTest {
   // Test for SI-8910
-  @Test def capacityExpansionTest() {
+  @Test def capacityExpansionTest(): Unit = {
     val bitSet = BitSet.empty
     val size   = bitSet.toBitMask.length
     bitSet ^= bitSet
@@ -20,7 +20,7 @@ class BitSetTest {
     assert(bitSet.toBitMask.length == size, "Capacity of bitset changed after &~=")
   }
   
-  @Test def test_SI8917() {
+  @Test def test_SI8917(): Unit = {
     val bigBitSet = BitSet(1, 100, 10000)
     val littleBitSet = BitSet(100)
     bigBitSet &= littleBitSet
@@ -29,10 +29,16 @@ class BitSetTest {
     assert(littleBitSet.toBitMask.length < bigBitSet.toBitMask.length, "Needlessly extended the size of bitset on &=")
   }
 
-  @Test def test_SI8647() {
+  @Test def test_SI8647(): Unit = {
     val bs = BitSet()
     bs.map(_ + 1)    // Just needs to compile
     val xs = bs: SortedSet[Int]
     xs.map(_ + 1)    // Also should compile (did before)
   }
+
+  @Test def t10164(): Unit = {
+    val bs = BitSet()
+    val last = (bs ++ (0 to 128)).last  // Just needs not to throw
+    assert(last == 128)
+  }
 }