   func testWillResignActive() {
     XCTAssert(
       SessionTestCase
-      .statesFrom { $0.applicationWillResignActive(UIApplication.shared) }
+      .statesFromCall { $0.applicationWillResignActive(UIApplication.shared) }
       .map { $0.state }
       ==
       [.none(.awaitingLaunch), .will(.resigned)]

    return output
  }
  
  static func statesFromStream(stream: Observable<Session.Model>) -> [Session.Model] {
    var output: [Session.Model] = []
    let session = Session(intitial: .empty, application: UIApplication.shared)
    _ = session
      .rendered(stream)
      .subscribe {

    let activity = NSUserActivity(activityType: "x")
    XCTAssert(
      SessionTestCase
      .statesFromCall {
        $0.application(
          UIApplication.shared,
          continue: activity,
