w = require('when')
childProcess = require('child_process')
{EventEmitter} = require('events')

sinon = require('sinon')
sinonChai = require("sinon-chai")
chai = require('chai')

chai.use(sinonChai)
expect = chai.expect

worker = require('../src/worker')

describe 'worker', ->

  spawn = null
  process = null

  beforeEach ->
    process = new EventEmitter
    process.kill = sinon.spy => process.emit 'exit'
    spawn = sinon.stub(childProcess, 'spawn')
      .returns(process)

  afterEach ->
    spawn.restore()


  it 'spawns child', ->
    worker('sleep', '1').start().then ->
      expect(spawn).calledOnce
      expect(spawn).calledWith('sleep', ['1'])

  it 'restarts on exit after grace period', ->
    clock = sinon.useFakeTimers()

    sleep = worker('sleep', gracePeriod: 500)
    sleep.start().then ->
      expect(spawn).calledOnce
      clock.tick(1000)
    .then ->
      restarted = w.promise (resolve)-> sleep.once 'restart', resolve
      process.kill()
      restarted
    .then ->
      expect(spawn).calledTwice
    .finally ->
      clock.restore()

  it 'kills process on restart', ->
    sleep = worker('sleep')

    sleep.start().tap (process)->
      expect(process.kill).not.called
      sleep.restart()
    .then ->
      expect(process.kill).calledOnce