1 files changed, 20 insertions, 0 deletions
diff --git a/test/junit/scala/collection/mutable/TreeSetTest.scala b/test/junit/scala/collection/mutable/TreeSetTest.scala
new file mode 100644
index 0000000000..50b004befc
--- /dev/null
+++ b/test/junit/scala/collection/mutable/TreeSetTest.scala
@@ -0,0 +1,20 @@
+package scala.collection.mutable
+
+import org.junit.Assert.assertEquals
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.junit.runners.JUnit4
+
+import scala.collection.mutable
+
+
+@RunWith(classOf[JUnit4])
+class TreeSetTest {
+
+  @Test
+  def rangeMkString() {
+
+    val set = mutable.TreeSet("a", "b", "c", "d")
+    assertEquals("b", set.range("b", "c").mkString(","))
+  }
+}