SOURCE

let list = [
    [
        {"id":"83876803","name":"早晨","imgUrl":"","k_s":"s1","k":"春季"},
        {"id":"97969517","name":"夏季","imgUrl":"","k_s":"s1","k":"春季"}
    ],
    [
        {"id":"60205102","name":"白1","k_s":"s2","k":"白色"}
    ],
    [
        {"id":"30012457","k":"红色","k_s":"s3","name":"红1"}
    ],
    [
        {"id":"02133206","k":"黑色","k_s":"s4","name":"黑1"}
    ]
]
let skuTree =  [
      {
        k: '颜色',
        k_s: 's1',
        v: [
          {id: '41660436', name: '白色', imgUrl: '', k_s: 's1', k: '颜色'}
        ]
      },
      {
        k: '重量',
        k_s: 's2',
        v: [
          {id: '41660426', name: '1kg', imgUrl: '', k_s: 's2', k: '重量'},
        ]
      }   
    ]
const f = (a, b) => [].concat(...a.map(d => b.map(e => [].concat(d, e))))
const cartesian = (a, b, ...c) => (b ? cartesian(f(a, b), ...c) : a)
const createNumberString = function (length, possibleString) {
  let text = ''
  const possible = possibleString || 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789'

  for (let i = 0; i < length; i++) {
    text += possible.charAt(Math.floor(Math.random() * possible.length))
  }

  return text
}
  function generateSkuList (skuTree) {
     // 根据sku tree变化重新生成sku list
     // 二维数组 skuValueArray: [ [{ k_s: 's1', k: '颜色', id: '30349678', name: '红色', imgUrl: 'xxx' }, { k_s... }], [{ k_s: 's2', ... }] ]
    let skuValue2DArray = [],skuList =  [], newSkuList = [], withPrice = false

    skuTree.forEach(tree => {
      let skuValueArray = []
      tree.v.forEach(valueItem => {
        skuValueArray.push(Object.assign(valueItem, { k_s: tree.k_s, k: tree.k }))
      })
      if (skuValueArray.length) {
        skuValue2DArray.push(skuValueArray)
      }
    })

    if (!skuValue2DArray.length) {
      this.setData({ skuList: [], totalStock: 0 })
      return []
    }

     // 笛卡尔组合 二维数组结果(如果只有一级规格s1，则数组对象是Object不是数组)
    const cartesianCombination = cartesian(...skuValue2DArray)
    console.log('cartesianCombination',cartesianCombination)
    let totalStock = 0
    cartesianCombination.forEach(ccArray => {
      let skuListItem = { stock_num: 0 }
      for (var i = 1; i <= 5; i++) {
        const sn = `s${i}`
        const ccItem = Array.isArray(ccArray) ? ccArray.find(cc => cc.k_s === sn) :
         (ccArray && ccArray.k_s === sn ? ccArray : null)
        if (ccItem) {
          skuListItem[sn] = ccItem.id
          const keyValueName = ccItem.k + ':' + ccItem.name
          skuListItem[sn + 'Name'] = keyValueName
          skuListItem['name'] = (skuListItem['name'] ? skuListItem['name'] + ',' : '') + keyValueName
        } else {
          skuListItem[sn] = '0'
        }
      }
       // skuList 如果已经存在，则使用其 id(skuId)和 stock_num，否则赋值新的 skuId
      const foundSkuListItem = skuList.find(sl => sl.s1 === skuListItem.s1 && sl.s2 === skuListItem.s2
         && sl.s3 === skuListItem.s3 && sl.s4 === skuListItem.s4 && sl.s5 === skuListItem.s5)
      if (foundSkuListItem) {
        skuListItem.id = foundSkuListItem.id
        skuListItem.stock_num = parseInt(foundSkuListItem.stock_num || 0)
        if (withPrice) {
           // 单位：分
          skuListItem.originalPrice = parseInt(foundSkuListItem.originalPrice || 0)
          skuListItem.price = parseInt(foundSkuListItem.price || 0)
        }
      } else {
        skuListItem.id = createNumberString(8)
      }

      totalStock += parseInt(skuListItem.stock_num)
      newSkuList.push(skuListItem)
    })
    return newSkuList
  }

//   console.log(generateSkuList(skuTree))