Method fields

packages/filter/src/query.ts:581–601

* Describe what fields to be included/excluded * @param f - A field name to be included, an array of field names to be * included, or an Fields object for the inclusion/exclusion

(...f: (Fields<MT> | Extract<keyof MT, string>)[])

   * included, or an Fields object for the inclusion/exclusion
   */
  fields(...f: (Fields<MT> | Extract<keyof MT, string>)[]): this {
    if (!this.filter.fields) {
      this.filter.fields = {};
    } else if (Array.isArray(this.filter.fields)) {
      this.filter.fields = this.filter.fields.reduce(
        (prev, current) => ({...prev, [current]: true}),
        {},
      );
    }
    const fields = this.filter.fields;
    for (const field of f) {
      if (Array.isArray(field)) {
        field.forEach(i => (fields[i] = true));
      } else if (typeof field === 'string') {
        fields[field] = true;
      } else {
        Object.assign(fields, field);
      }
    }
    return this;
  }

  private validateOrder(order: string) {
    assert(order.match(/^[^\s]+( (ASC|DESC))?$/), 'Invalid order: ' + order);