adding specs test for button observer

Author: mdodsworth

observer-testing.scala

@@ -0,0 +1,16 @@
+package ui
+
+import observer._
+
+class ObservableButton(name :String) extends Button(name) with Subject {
+    override def click() = {
+        super.click()
+        println("this is a test")
+        notifyObservers
+    }
+}
+
+class ButtonCounter {
+    var count = 0
+    def receiveUpdate(subject :Any) = count += 1
+}

observer.scala

@@ -0,0 +1,10 @@
+package observer
+
+trait Subject {
+    type Observer = { def receiveUpdate(subject :Any) }
+    
+    private var observers = List[Observer]()
+    def addObserver(observer :Observer) = observers ::= observer
+    def notifyObservers = observers foreach(_.receiveUpdate(this))
+}
+

specs-test.scala

@@ -0,0 +1,17 @@
+package ui
+
+import org.specs._
+import observer._
+
+object ButtonObserverSpec extends Specification {
+    "A button observer" should {
+        "observer button clicks" in {
+            val observableButton = new ObserverableButton("Testing")
+            val buttonObserver = new ButtonCounter
+            observableButton addObserver buttonObserver
+
+            for (i <- 1 to 3) observableButton.click()
+            buttonObserver.count mustEqual 3
+        }
+    }
+}

widget.scala

@@ -0,0 +1,8 @@
+package ui
+
+abstract class Widget
+
+class Button(val name:String) extends Widget {
+    def click() = println("the user clicked something")
+}
+