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

  /** A task runner that posts tasks to this fake. Tasks won't be executed until requested. */
  val taskRunner: TaskRunner =
    TaskRunner(
      object : TaskRunner.Backend {
        override fun execute(
          taskRunner: TaskRunner,
          runnable: Runnable,
        ) {
          taskRunner.assertThreadHoldsLock()

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

  private val runnable: Runnable =
    object : Runnable {
      override fun run() {
        var incrementedRunCallCount = false
        while (true) {
          val task =
            ******@****.***ck {
              if (!incrementedRunCallCount) {

    )
  }

  /** Repeat with a delay of 200 but schedule with a delay of 50. The schedule wins. */
  @Test fun executeScheduledEarlierReplacesRepeatedLater() {
    val task =
      object : Task("task") {
        val schedules = mutableListOf(50.µs)
        val delays = mutableListOf(200.µs, -1)

        override fun runOnce(): Long {
          log += "run@${taskFaker.nanoTime}"