private var waitingCoordinatorTask: SerialTask? = null
  private var waitingCoordinatorInterrupted = false
  private var waitingCoordinatorNotified = false

  /** How many times a new task has been started. Guarded by [TaskRunner.lock]. */
  private var contextSwitchCount = 0

  /** Guarded by [TaskRunner.lock]. */
  private var activeThreads = 0

   */
  private var executeCallCount = 0
  private var runCallCount = 0

  /** Queues with tasks that are currently executing their [TaskQueue.activeTask]. */
  private val busyQueues = mutableListOf<TaskQueue>()

  /** Queues not in [busyQueues] that have non-empty [TaskQueue.futureTasks]. */
  private val readyQueues = mutableListOf<TaskQueue>()

  private val runnable: Runnable =
    object : Runnable {

class TaskRunnerTest {
  private val taskFaker = TaskFaker()

  @RegisterExtension @JvmField
  val testLogHandler = TestLogHandler(taskFaker.logger)

  private val taskRunner = taskFaker.taskRunner
  private val log = mutableListOf<String>()
  private val redQueue = taskRunner.newQueue()
  private val blueQueue = taskRunner.newQueue()
  private val greenQueue = taskRunner.newQueue()

  @AfterEach