Rearrange data according to date JS

Catalog

demand ：

Source data ：

Data to be converted ：

Realize the idea ：

Complete code ：

demand ：

Merge the data into the original array according to the date

Source data ：

    var arr = [
      { createTime: "2022-07-14 ", taskName: " Improve personal information ", experiencePoints: '2' },
      { createTime: "2022-07-14 ", taskName: " Order for the first time ", experiencePoints: '2' },
      { createTime: "2022-07-13 ", taskName: " Check in every day ", experiencePoints: '2' },
      { createTime: "2022-07-14 ", taskName: " Check in every day ", experiencePoints: '2' },
    ]

Data to be converted ：

var arr2 = [
      {
        createTime: "2022-07-14 ",
        list: [
          { taskName: " Improve personal information ", experiencePoints: '2' },
          { taskName: " Order for the first time ", experiencePoints: '2' },
          { taskName: " Check in every day ", experiencePoints: '2' },
        ],
      },
      {
        createTime: "2022-07-13 ",
        list: [
          { taskName: " Check in every day ", experiencePoints: '2' },
        ],
      }
    ]

Realize the idea ：

1. In a glance , It is to divide the data according to the date , Then the first thing is to remove the duplicate of the array , Retain the period of no duplication

2. The next step is to assemble data , If the dates are equal, add list

Complete code ：

 var arr = [ // Initial code 
      { createTime: "2022-07-14 ", taskName: " Improve personal information ", experiencePoints: '2' },
      { createTime: "2022-07-14 ", taskName: " Order for the first time ", experiencePoints: '2' },
      { createTime: "2022-07-13 ", taskName: " Check in every day ", experiencePoints: '2' },
      { createTime: "2022-07-14 ", taskName: " Check in every day ", experiencePoints: '2' },
    ]

    var arr2 = [ // Object code 
      {
        createTime: "2022-07-14 ",
        list: [
          { taskName: " Improve personal information ", experiencePoints: '2' },
          { taskName: " Order for the first time ", experiencePoints: '2' },
          { taskName: " Check in every day ", experiencePoints: '2' },
        ],
      },
      {
        createTime: "2022-07-13 ",
        list: [
          { taskName: " Check in every day ", experiencePoints: '2' },
        ],
      }
    ]
// Logical part 
    let demo3 = [...new Set(arr.map(item => item.createTime))] //['2022-07-14 ', '2022-07-13 ']

    let end = []
    demo3.forEach((i, o) => {
      end.push({ createTime: i, list: [] })
    })
    end.forEach((it, id) => {
      arr.forEach((item, index) => {
        if (it.createTime == item.createTime) {
          it.list.push({ taskName: item.taskName, experiencePoints: item.experiencePoints })
        }
      })
    })
    console.log(end, '------------------------------')