Function stateMixin

static/vuejs/vue.common.js:2870–2912

(Vue)

}

function stateMixin (Vue) {
  // flow somehow has problems with directly declared definition object
  // when using Object.defineProperty, so we have to procedurally build up
  // the object here.
  var dataDef = {};
  dataDef.get = function () { return this._data };
  var propsDef = {};
  propsDef.get = function () { return this._props };
  if (process.env.NODE_ENV !== 'production') {
    dataDef.set = function (newData) {
      warn(
        'Avoid replacing instance root $data. ' +
        'Use nested data properties instead.',
        this
      );
    };
    propsDef.set = function () {
      warn("$props is readonly.", this);
    };
  }
  Object.defineProperty(Vue.prototype, '$data', dataDef);
  Object.defineProperty(Vue.prototype, '$props', propsDef);

  Vue.prototype.$set = set;
  Vue.prototype.$delete = del;

  Vue.prototype.$watch = function (
    expOrFn,
    cb,
    options
  ) {
    var vm = this;
    options = options || {};
    options.user = true;
    var watcher = new Watcher(vm, expOrFn, cb, options);
    if (options.immediate) {
      cb.call(vm, watcher.value);
    }
    return function unwatchFn () {
      watcher.teardown();
    }
  };
}

/*  */