File3.swift

class AnimatorSpy: Animator {

  var invokedAnimate = false
  var invokedAnimateCount = 0
  var invokedAnimateParameters: (duration: TimeInterval, Void)?
  var invokedAnimateParametersList = [(duration: TimeInterval, Void)]()
  var shouldInvokeAnimateAnimations = false
  var stubbedAnimateCompletionResult: (Bool, Void)?
  var stubbedAnimateResult: Bool! = false

  func animate(duration: TimeInterval, animations: () -> (), completion: (Bool) -> ()) -> Bool {
    invokedAnimate = true
    invokedAnimateCount += 1
    invokedAnimateParameters = (duration, ())
    invokedAnimateParametersList.append((duration, ()))
    if shouldInvokeAnimateAnimations {
      animations()
    }
    if let result = stubbedAnimateCompletionResult {
      completion(result.0)
    }
    return stubbedAnimateResult
  }
}