Flutter Freezed/json_serializable - 生成的 json 中缺少 runtimeType

如何解决Flutter Freezed/json_serializable - 生成的 json 中缺少 runtimeType

出于某种原因，此 Freezed 类生成的 json 中缺少 runtimeType。它只是偶尔发生。见下图：

这会导致图像中的 switch case 变为 throw FallThroughError();，因为 runtimeType 不存在。

这是课程：

import 'package:freezed_annotation/freezed_annotation.dart';
import 'package:vepo/src/application/entities/option/option.dart';
import '../vegan_item.dart';

part 'basic_vegan_item.freezed.dart';
part 'basic_vegan_item.g.dart';

@freezed
class BasicVeganItem extends VeganItem with _$BasicVeganItem {
  const factory BasicVeganItem(
      {int? id,String? name,String? companyName,String? imageBucketName,String? description,String? image,List<Option>? tags,@Default(0) int isNotVeganCount,@Default(0) int isveganCount,int? rating,@Default(0) int ratingsCount,@Default(1) int currentRevisionId}) = _BasicVeganItem;

  const factory BasicVeganItem.groceryItem(
      {int? id,@Default('vp-grocery-items') String? imageBucketName,@Default(1) int currentRevisionId}) = GroceryItem;

  const factory BasicVeganItem.menuItem(
      {int? id,@Default('vp-menu-items') String? imageBucketName,@Default(1) int currentRevisionId}) = MenuItem;

  const BasicVeganItem._();

  factory BasicVeganItem.fromJson(Map<String,dynamic> json) =>
      _$BasicVeganItemFromJson(json);
}