mona-tool-cli/src/core/spinner.js

Mona系列-开发者命令行工具

var sprintf = require('util').format

// Make a console spinner.
// Code based on code from Mocha by Visionmedia/Tj
// https://github.com/visionmedia/mocha/blob/master/bin/_mocha
function Spinner (message) {
  var spinnerMessage = message
  
  this.start = function (opts) {
    var opts = opts || {}
    var self = this
    var spinner = 'win32' == process.platform ? ['|', '/', '-', '\\'] : ['◜', '◠', '◝', '◞', '◡', '◟']
    
    function play (arr, interval) {
      var len = arr.length, i = 0
      interval = interval || 100
      
      var drawTick = function () {
        var str = arr[i++ % len]
        process.stdout.write('\u001b[0G' + str + '\u001b[90m' + spinnerMessage + '\u001b[0m')
      }
      
      self.timer = setInterval(drawTick, interval)
    }
    
    var frames = spinner.map(function (c) {
      return sprintf('  \u001b[96m%s ', c)
    })
    
    play(frames, opts.fps || 30)
  }
  
  this.message = function (message) {
    spinnerMessage = message
  }
  
  this.stop = function () {
    process.stdout.write('\u001b[0G\u001b[2K')
    clearInterval(this.timer)
  }
}

module.exports = Spinner