pnpm/lib/node_modules/most/src/combinator/delay.js

Fast, disk space efficient package manager

/** @license MIT License (c) copyright 2010-2016 original author or authors */
/** @author Brian Cavalier */
/** @author John Hann */

import Stream from '../Stream'
import Pipe from '../sink/Pipe'
import * as dispose from '../disposable/dispose'
import PropagateTask from '../scheduler/PropagateTask'

/**
 * @param {Number} delayTime milliseconds to delay each item
 * @param {Stream} stream
 * @returns {Stream} new stream containing the same items, but delayed by ms
 */
export function delay (delayTime, stream) {
  return delayTime <= 0 ? stream
    : new Stream(new Delay(delayTime, stream.source))
}

function Delay (dt, source) {
  this.dt = dt
  this.source = source
}

Delay.prototype.run = function (sink, scheduler) {
  var delaySink = new DelaySink(this.dt, sink, scheduler)
  return dispose.all([delaySink, this.source.run(delaySink, scheduler)])
}

function DelaySink (dt, sink, scheduler) {
  this.dt = dt
  this.sink = sink
  this.scheduler = scheduler
}

DelaySink.prototype.dispose = function () {
  var self = this
  this.scheduler.cancelAll(function (scheduledTask) {
    return scheduledTask.task.sink === self.sink
  })
}

DelaySink.prototype.event = function (t, x) {
  this.scheduler.delay(this.dt, PropagateTask.event(x, this.sink))
}

DelaySink.prototype.end = function (t, x) {
  this.scheduler.delay(this.dt, PropagateTask.end(x, this.sink))
}

DelaySink.prototype.error = Pipe.prototype.error