Merge pull request #7 from svenvanheugten/add-more-tests

Add a test that verifies that the remote turns on the lights

NightLight.Core.Tests/NightLightTests.fs

@@ -23,6 +23,16 @@ type NightLightTests() =
 
         fakeHome
 
+    let doesLightHavePowerAfter interactions light =
+        interactions
+        |> Seq.choose (fun interaction ->
+            match interaction with
+            | HumanInteraction(LightPoweredOff l) when l = light -> Some false
+            | HumanInteraction(LightPoweredOn l) when l = light -> Some true
+            | _ -> None)
+        |> Seq.tryLast
+        |> Option.defaultValue false
+
     [<Property>]
     let ``All lights that are on should be white or yellow during the day`` () =
         genTimeChangedToDay
@@ -43,6 +53,24 @@ type NightLightTests() =
             let fakeHome = createFakeHomeWithNightLightAndInteract interactions
             fakeHome.ForAllLightsThatAreOn(fun (_, _, color) -> color = Red)
 
+    [<Property>]
+    let ``After pressing 'On' on the remote, the remotely controlled lights that have power should be on until they are powered off or 'Off' is pressed``
+        ()
+        =
+        genInteractionListContaining (HumanInteraction RemotePressedOnButton) (function
+            | HumanInteraction RemotePressedOffButton -> true
+            | HumanInteraction(LightPoweredOff l) when l.ControlledWithRemote -> true
+            | _ -> false)
+        |> Arb.fromGen
+        |> Prop.forAll
+        <| fun interactions ->
+            let fakeHome = createFakeHomeWithNightLightAndInteract interactions
+
+            fakeHome.LightStates
+            |> Seq.filter (fst >> doesLightHavePowerAfter interactions)
+            |> Seq.map snd
+            |> Seq.forall _.IsOn
+
     [<Property>]
     let ``After pressing 'Off' on the remote, the remotely controlled lights should stay off until 'On' is pressed``
         ()