如何检查Sequelize中是否存在belongsToMany关联

const { Sequelize, Model, DataTypes } = require('sequelize');

// 导入其他模型
const User = require('./user');
const Role = require('./role');

// 定义User模型
class User extends Model {}
User.init({
  // 用户属性
}, { sequelize, modelName: 'user' });

// 定义Role模型
class Role extends Model {}
Role.init({
  // 角色属性
}, { sequelize, modelName: 'role' });

// 定义User和Role之间的多对多关联
User.belongsToMany(Role, { through: 'UserRole' });
Role.belongsToMany(User, { through: 'UserRole' });

const hasBelongsToMany = User.associations.hasOwnProperty('Roles') && Role.associations.hasOwnProperty('Users');

if (hasBelongsToMany) {
  console.log('存在belongsToMany关联');
} else {
  console.log('不存在belongsToMany关联');
}