1 files changed, 89 insertions, 0 deletions
diff --git a/test/files/scalacheck/treeset.scala b/test/files/scalacheck/treeset.scala
new file mode 100644
index 0000000000..3cefef7040
--- /dev/null
+++ b/test/files/scalacheck/treeset.scala
@@ -0,0 +1,89 @@
+import collection.immutable._
+import org.scalacheck._
+import Prop._
+import Gen._
+import Arbitrary._
+import util._
+
+object Test extends Properties("TreeSet") {
+  implicit def arbTreeSet[A : Arbitrary : Ordering]: Arbitrary[TreeSet[A]] =
+    Arbitrary(listOf(arbitrary[A]) map (elements => TreeSet(elements: _*)))
+
+  property("foreach/iterator consistency") = forAll { (subject: TreeSet[Int]) =>
+    val it = subject.iterator
+    var consistent = true
+    subject.foreach { element =>
+      consistent &&= it.hasNext && element == it.next
+    }
+    consistent
+  }
+
+  property("sorted") = forAll { (subject: TreeSet[Int]) => (subject.size >= 3) ==> {
+    subject.zip(subject.tail).forall { case (x, y) => x < y }
+  }}
+
+  property("contains all") = forAll { (elements: List[Int]) =>
+    val subject = TreeSet(elements: _*)
+    elements.forall(subject.contains)
+  }
+
+  property("size") = forAll { (elements: List[Int]) =>
+    val subject = TreeSet(elements: _*)
+    elements.distinct.size == subject.size
+  }
+
+  property("toSeq") = forAll { (elements: List[Int]) =>
+    val subject = TreeSet(elements: _*)
+    elements.distinct.sorted == subject.toSeq
+  }
+
+  property("head") = forAll { (elements: List[Int]) => elements.nonEmpty ==> {
+    val subject = TreeSet(elements: _*)
+    elements.min == subject.head
+  }}
+
+  property("last") = forAll { (elements: List[Int]) => elements.nonEmpty ==> {
+    val subject = TreeSet(elements: _*)
+    elements.max == subject.last
+  }}
+
+  property("head/tail identity") = forAll { (subject: TreeSet[Int]) => subject.nonEmpty ==> {
+    subject == (subject.tail + subject.head)
+  }}
+
+  property("init/last identity") = forAll { (subject: TreeSet[Int]) => subject.nonEmpty ==> {
+    subject == (subject.init + subject.last)
+  }}
+
+  property("take") = forAll { (subject: TreeSet[Int]) =>
+    val n = choose(0, subject.size).sample.get
+    n == subject.take(n).size && subject.take(n).forall(subject.contains)
+  }
+
+  property("drop") = forAll { (subject: TreeSet[Int]) =>
+    val n = choose(0, subject.size).sample.get
+    (subject.size - n) == subject.drop(n).size && subject.drop(n).forall(subject.contains)
+  }
+
+  property("take/drop identity") = forAll { (subject: TreeSet[Int]) =>
+    val n = choose(-1, subject.size + 1).sample.get
+    subject == subject.take(n) ++ subject.drop(n)
+  }
+
+  property("splitAt") = forAll { (subject: TreeSet[Int]) =>
+    val n = choose(-1, subject.size + 1).sample.get
+    val (prefix, suffix) = subject.splitAt(n)
+    prefix == subject.take(n) && suffix == subject.drop(n)
+  }
+
+  property("remove single") = forAll { (subject: TreeSet[Int]) => subject.nonEmpty ==> {
+    val element = oneOf(subject.toSeq).sample.get
+    val removed = subject - element
+    subject.contains(element) && !removed.contains(element) && subject.size - 1 == removed.size
+  }}
+
+  property("remove all") = forAll { (subject: TreeSet[Int]) =>
+    val result = subject.foldLeft(subject)((acc, elt) => acc - elt)
+    result.isEmpty
+  }
+}