anchor.diff:      schemaUpdated
   
     override this.TestResults =
  -    testResults :> IObservable<_>
  +    testResults
   
     override this.Start() =
       start ()
  
positive.code:       )
  
    let testResults =
      new Subject<_>()
  
    let subscription =
      new SingleAssignmentDisposable()
  
negative.code:     cancel ()
      match OneshotTestAssembly.ofFile file with
      | Success testAssembly ->
        currentTestSchema.Value <- testAssembly.Schema
        currentTestAssembly.Value <- Some testAssembly
        testAssembly.Start()
      | Failure e ->
  