SOURCE

test=() => {
    const arr = [
      {
        cycleId: 1,
        cycleName: '循环1',
        parentCycleId: 0,
        type: 'cycle',
        versionId: 167,
        versionName: '0.1.0',
        versionStatusName: '规划中',
      }, {
        cycleId: 1,
        cycleName: '循环1',
        parentCycleId: 0,
        type: 'cycle',
        versionId: 167,
        versionName: '0.1.0',
        versionStatusName: '规划中',
      }, {
        cycleId: 1,
        cycleName: '循环1',
        parentCycleId: 0,
        type: 'cycle',
        versionId: 167,
        versionName: '0.1.0',
        versionStatusName: '规划中',
      }, {
        cycleId: 1,
        cycleName: '循环1',
        parentCycleId: 0,
        type: 'cycle',
        versionId: 167,
        versionName: '0.1.0',
        versionStatusName: '规划中',
      },
    ];
    const result = this.sss(arr, 'versionStatusName');
    window.console.log(result);
    result.forEach((s) => {
      s.children = this.sss(s.children, 'versionName');
    });
    // result = result.map(s => this.sss(s.children, 'versionName'));
    window.console.log(result); 
  }
  sss=(arr, key) => {
    const result = arr.reduce((groups, item) => {
      const groupFound = 
      groups.find(arrItem => item.title === arrItem[key]);
      if (groupFound) {       
        groupFound.children.push(item);   
      } else {
        // 不要直接在原来的对象修改，新建对象
        const newGroup = {
          title: item[key],

          children: [item],
        };
        groups.push(newGroup);
      }
      return groups;
    }, []);
    return result;
  }