gulpfile.js

var gulp = require('gulp');
var uglify = require('gulp-uglifyjs');
 
gulp.task('uglify', function() {
  gulp.src('./my.js')
    .pipe(uglify())
    .pipe(gulp.dest('./build'))
});

my.js

class UserRegisterService {
  constructor(content){
    var that = this;

    this.content = {
      element: $(content),
      text: content
    };
    this.isLoading = false;
    this.sending = false;
    this.buttons = {
      send: $(this.content.text + ' a[href="#send"]')
    };
    this.fields = {
      phone: $(this.content.text + ' input[name="phone"]')
    };

    this.buttons.send.on('click touchstart', function(){
      that.send();
      return false;
    });

    this.content.element.submit(function(event){
      that.send();
      return false;
    });

    this.fields.phone.keypress(function(e){
      if (e.keyCode == 13) that.send();
      if (e.keyCode == 43 || e.keyCode == 45 || e.keyCode == 13) return false;
      if (that.fields.phone.val().length >= 9) return false;
    });
  }

  loading(status){
    this.isLoading = status;
    if (status == true){
      this.buttons.send
        .addClass('disabled')
        .html('<i class="fa fa-spinner fa-spin fa-fw"></i><span class="sr-only">Пожалуйста, подождите...</span>');
    } else {
      this.buttons.send
        .removeClass('disabled')
        .html('Отправить код');
    }
  }

  send(){
    if (!this.sending){
      var that = this;
      if (!_empty(this.fields.phone.val())){
        this.loading(true);
        this.sending = true;
        new RequestService()
          .post({
            action: 'userRegister',
            phone: this.fields.phone.val()
          }).then(function(resolve){
            that.loading(false);
            that.sending = false;
            switch(resolve){
              case 'confirm':
                new StorageService().set('phone_register_confirm', that.fields.phone.val());
                window.location = '/user/register/confirm';
                break;
              case 'success':
                new StorageService().set('phone_register_confirm', that.fields.phone.val());
                window.location = '/user/register/confirm';
                break;
              case 'unknown_error':
                error.unknown();
                break;
              case 'exists':
                swal({
                  title: 'Ошибка!',
                  text: 'Вы уже регистрировались в системе! Пожалуйста, войдите.',
                  type: 'error'
                }).then(function(){
                  window.location = '/user/login';
                }, function(dismiss){});
                break;
              case 'wrong_data':
                swal({
                  title: 'Ошибка',
                  text: 'Неверный телефонный номер!',
                  type: 'error'
                });
                break;
              default: error.unknown(); break;
            }
          }, function(reject){
            that.loading(false);
            that.sending = false;
          });
      } else {
        swal({
          title: 'Ошибка',
          text: 'Неверный телефонный номер!',
          type: 'error'
        });
      }
    }
  }
}