JavaScript 过滤多层数据结构

Question

let promotGroups = [
            {
                "promotionId":"1111111111",
                "promotionName":"",
                "promotionDescription":"",
                "havePromotion":false,
                "classes":[
                    {
                        "classId":"77777777777777",
                        "tutorPictureUrl":"",
                        "teachers":[
                            {
                                "teacherId":"bf2ab5882d9e470a825eee97541d8868",
                                "teacherName":"张亚飞测试",
                                "name":"张亚飞测试",
                                "realName":"张亚飞测试",
                                "sex":0,
                                "pictureUrl":""
                            }
                        ],
                        "goodsType":0,
                    },
                    {
                        "classId":"1111111111111111111",
                        "tutorPictureUrl":"",
                        "teachers":[
                            {
                                "teacherId":"bf2ab5882d9e470a825eee97541d8868",
                                "teacherName":"张亚飞测试",
                                "name":"张亚飞测试",
                                "realName":"张亚飞测试",
                                "sex":0,
                                "pictureUrl":""
                            }
                        ],
                        "goodsType":0,
                    }
                ]
            },
             {
                "promotionId":"2222222222",
                "promotionName":"",
                "promotionDescription":"",
                "havePromotion":false,
                "classes":[
                    {
                        "classId":"6e64da1f52694f608293267c87865ce3",
                        "tutorPictureUrl":"",
                        "teachers":[
                            {
                                "teacherId":"bf2ab5882d9e470a825eee97541d8868",
                                "teacherName":"张亚飞测试",
                                "name":"张亚飞测试",
                                "realName":"张亚飞测试",
                                "sex":0,
                                "pictureUrl":""
                            }
                        ],
                        "goodsType":0,
                    },
                    {
                        "classId":"000000000",
                        "tutorPictureUrl":"",
                        "teachers":[
                            {
                                "teacherId":"bf2ab5882d9e470a825eee97541d8868",
                                "teacherName":"张亚飞测试",
                                "name":"张亚飞测试",
                                "realName":"张亚飞测试",
                                "sex":0,
                                "pictureUrl":""
                            }
                        ],
                        "goodsType":0,
                    }
                ]
            }
        ]

我想要过滤的结果还是上面的那样 只是不同的 classes 取值不一致？
请问一下 怎么过滤？？
理想的结构：

let new = [
            {
                "id":"1111111111",
              
                "newarr":[
                    {
                        "id":"77777777777777",
                        "teachers":[
                            {
                                "teacherId":"bf2ab5882d9e470a825eee97541d8868",
                                "teacherName":"张亚飞测试",
                                "name":"张亚飞测试",
                                "realName":"张亚飞测试",
                                "sex":0,
                                "pictureUrl":""
                            }
                        ],
                        "goodsType":0,
                    },
                    {
                        "classId":"1111111111111111111",
                        "tutorPictureUrl":"",
                        "teachers":[
                            {
                                "teacherId":"bf2ab5882d9e470a825eee97541d8868",
                                "teacherName":"张亚飞测试",
                                "name":"张亚飞测试",
                                "realName":"张亚飞测试",
                                "sex":0,
                                "pictureUrl":""
                            }
                        ],
                    }
                ]
            },
             {
                "id":"2222222222222",
              
                "newarr":[
                    {
                        "id":"00000000000000",
                        "teachers":[
                            {
                                "teacherId":"bf2ab5882d9e470a825eee97541d8868",
                                "teacherName":"张亚飞测试",
                                "name":"张亚飞测试",
                                "realName":"张亚飞测试",
                                "sex":0,
                                "pictureUrl":""
                            }
                        ],
                        "goodsType":0,
                    },
                    {
                        "classId":"1111111111111111111",
                        "tutorPictureUrl":"",
                        "teachers":[
                            {
                                "teacherId":"bf2ab5882d9e470a825eee97541d8868",
                                "teacherName":"张亚飞测试",
                                "name":"张亚飞测试",
                                "realName":"张亚飞测试",
                                "sex":0,
                                "pictureUrl":""
                            }
                        ],
                    }
                ]
            },
        ]

Answer 1

//多层map能返回你想要的结果

promotGroups.map(item => {
  return {
    id: item.promotionId, newarr: item.classes.map(val => {
      return {id:val.classId,goodsType:val.goodsType,teachers:val.teachers}
    })
  }
})

Answer 2

js map 循环 return