4 files changed, 46 insertions, 2 deletions
diff --git a/src/main/scala/Chisel/testers/Driver.scala b/src/main/scala/Chisel/testers/Driver.scala
index 23c34f3a..a46c493c 100644
--- a/src/main/scala/Chisel/testers/Driver.scala
+++ b/src/main/scala/Chisel/testers/Driver.scala
@@ -33,7 +33,7 @@ import Chisel._
 
 object TesterDriver {
   def execute(t: => BasicTester): Boolean = {
-    val circuit = Builder.build(t)
+    val circuit = Builder.build(Module(t))
     //val executable = invokeFIRRTL(circuit)
     //Process(executable) !
     true
diff --git a/src/test/scala/chiselTests/BitwiseOps.scala b/src/test/scala/chiselTests/BitwiseOps.scala
index c4fe7424..5a1f1de8 100644
--- a/src/test/scala/chiselTests/BitwiseOps.scala
+++ b/src/test/scala/chiselTests/BitwiseOps.scala
@@ -53,7 +53,7 @@ class BitwiseOps(w: Int) extends Module {
 class BitwiseOpsSpec extends ChiselPropSpec {
 
   class BitwiseOpsTester(w: Int, a: Int, b: Int) extends BasicTester {
-    val mask = (1 << w)-1;
+    val mask = (1 << w) - 1
     val dut = Module(new BitwiseOps(w))
     io.done := Bool(true)
     dut.io.a := UInt(a) 
diff --git a/src/test/scala/chiselTests/ChiselSpec.scala b/src/test/scala/chiselTests/ChiselSpec.scala
index f3dad3dc..e9ec2dae 100644
--- a/src/test/scala/chiselTests/ChiselSpec.scala
+++ b/src/test/scala/chiselTests/ChiselSpec.scala
@@ -38,6 +38,9 @@ import Chisel.testers._
 class ChiselPropSpec extends PropSpec with PropertyChecks {
   def execute(t: => BasicTester): Boolean = TesterDriver.execute(t)
 
+  def popCount(n: Long) = n.toBinaryString.count(_=='1')
+
+  val smallPosInts = Gen.choose(1, 16)
   val safeUIntWidth = Gen.choose(1, 31) 
   val safeUInts = Gen.choose(0, (1 << 30))
   val vecSizes = Gen.choose(0, 4)
diff --git a/src/test/scala/chiselTests/Counter.scala b/src/test/scala/chiselTests/Counter.scala
new file mode 100644
index 00000000..90e3afa3
--- /dev/null
+++ b/src/test/scala/chiselTests/Counter.scala
@@ -0,0 +1,41 @@
+package chiselTests
+import Chisel._
+import org.scalatest._
+import org.scalatest.prop._
+import Chisel.testers.BasicTester
+
+class CounterSpec extends ChiselPropSpec {
+
+  class CountTester(max: Int) extends BasicTester {
+    val cnt = Counter(max)
+    when(cnt.value === UInt(max)) { io.done := Bool(true) }
+  }
+
+  property("Counter should count up") {
+    forAll(smallPosInts) { (max: Int) => assert(execute{ new CountTester(max) }) }
+  }
+
+  class EnableTester(seed: Int) extends BasicTester {
+    val ens = Reg(init = UInt(seed))
+    ens := ens >> 1
+    val (cntEn, cntWrap) = Counter(ens(0), 32)
+    val cnt = Counter(32)
+    when(cnt.value === UInt(31)) {
+      io.done := Bool(true) 
+      io.error := cnt.value != UInt(popCount(seed))
+    }
+  }
+
+  property("Counter can be en/disabled") {
+    forAll(safeUInts) { (seed: Int) => assert(execute{ new EnableTester(seed) }) }
+  }
+
+  class WrapTester(max: Int) extends BasicTester {
+    val (cnt, wrap) = Counter(Bool(true), max)
+    when(wrap) { io.done := Bool(true); io.error := cnt != UInt(max) }
+  }
+
+  property("Counter should wrap") {
+    forAll(smallPosInts) { (max: Int) => assert(execute{ new WrapTester(max) }) }
+  }
+}