private ScheduledFuture<@Nullable Void> submitToExecutor(Schedule schedule) {
        return executor.schedule(this, schedule.delay, schedule.unit);
      }
    }

    /**
     * Contains the most recently submitted {@code Future}, which may be cancelled or updated,
     * always under a lock.
     */
    private static final class SupplantableFuture implements Cancellable {
      private final ReentrantLock lock;

    // If the task is already scheduled, take the earlier of the two times.
    val existingIndex = futureTasks.indexOf(task)
    if (existingIndex != -1) {
      if (task.nextExecuteNanoTime <= executeNanoTime) {
        taskRunner.logger.taskLog(task, this) { "already scheduled" }
        return false
      }
      futureTasks.removeAt(existingIndex) // Already scheduled later: reschedule below!
    }

      object : Task("task one") {
        val schedules = mutableListOf(200.µs)

        override fun runOnce(): Long {
          if (schedules.isNotEmpty()) {
            redQueue.schedule(this, schedules.removeAt(0)) // Add it at the end also.
          }
          log += "scheduledTasks=${redQueue.scheduledTasks}"
          return -1L
        }
      }
    redQueue.schedule(task, 100.µs)

 * ----------
 *
 * Tasks control their recurrence schedule. The [runOnce] function returns -1L to signify that the
 * task should not be executed again. Otherwise it returns a delay until the next execution.
 *
 * A task has at most one next execution. If the same task instance is scheduled multiple times, the
 * earliest one wins. This applies to both executions scheduled with [TaskRunner.Queue.schedule] and
 * those implied by the returned execution delay.

                schedule {
                    schedulingPolicy = daily {
                        this.hour = triggerHour
                    }
                    triggerBuild = always()
                    withPendingChangesOnly = true
                    enabled = branch.enableVcsTriggers
                    // https://www.jetbrains.com/help/teamcity/2022.04/configuring-schedule-triggers.html#general-syntax-1

  }

  @Test fun taskFailsWithUncheckedException() {
    queue.schedule("task", TimeUnit.MILLISECONDS.toNanos(100)) {
      log.put("failing task running")
      throw RuntimeException("boom!")
    }

    queue.schedule("task", TimeUnit.MILLISECONDS.toNanos(200)) {
      log.put("normal task running")
      return@schedule -1L
    }

    queue.idleLatch().await(500, TimeUnit.MILLISECONDS)

version: 2
updates:

  - package-ecosystem: "maven"
    directory: "/"
    schedule:
      interval: "daily"

  - package-ecosystem: maven
    directory: "/"
    schedule:
      interval: "daily"
    target-branch: "maven-3.9.x"
    labels:
      - "mvn3"

  - package-ecosystem: "github-actions"
    directory: "/"
    schedule:

}

// CronJobSpec describes how the job execution will look like and when it will actually run.
message CronJobSpec {
  // The schedule in Cron format, see https://en.wikipedia.org/wiki/Cron.
  optional string schedule = 1;

  // The time zone name for the given schedule, see https://en.wikipedia.org/wiki/List_of_tz_database_time_zones.
  // If not specified, this will default to the time zone of the kube-controller-manager process.

# easily import the generated PRs into our internal repo.
#  - package-ecosystem: "maven"
#    directory: "/"
#    schedule:
#      interval: "weekly"
#    groups:
#      dependencies:
#        applies-to: version-updates
#        patterns:
#          - "*"
#  - package-ecosystem: "maven"
#    directory: "/android"
#    schedule:
#      interval: "weekly"
#    groups:
#      dependencies:
#        applies-to: version-updates

    return new NoOpScheduledExecutorService();
  }

  /**
   * Creates a scheduled executor service that runs each task in the thread that invokes {@code
   * execute/submit/schedule}, as in {@link CallerRunsPolicy}. This applies both to individually
   * submitted tasks and to collections of tasks submitted via {@code invokeAll}, {@code invokeAny},
   * {@code schedule}, {@code scheduleAtFixedRate}, and {@code scheduleWithFixedDelay}. In the case