docs: function (store, type, fixtureRecord) {
      var fixture = fixtureRecord || {};
      type = this._parseModelOrType(store, type);
      if (!fixtureRecord.id) {
        fixtureRecord.id = this.generateId(store, type);
      }
      if (this.fixtureForId(store, type, fixture.id)) {
        throw new Error('Fixture `' + type.typeKey + '` with id `' + fixture.id + '` already exists.');
      }
      return this.updateFixtures(store, type, fixture);
    }