使用 TypeScript 实现类型安全的通用分组求和函数

/**
 * 对对象数组中的对象值进行求和，按任意对象键分组。
 *
 * @remarks
 * 此方法接受并返回一个对象数组。
 * 生成的对象数组包含原始数组中对象键的子集。
 *
 * @param arr - 要分组和求和的对象数组。
 * @param groupByKeys - 用于分组的键的数组。
 * @param sumKeys - 用于求和的键的数组。这些键必须引用
 *    数值。
 * @returns 一个对象数组，按 groupByKeys 分组，并对 sumKeys 中的键的值求和。
 */
const groupBySum = <T, K extends keyof T, S extends keyof T>(
  arr: T[],
  groupByKeys: K[],
  sumKeys: S[]
): Pick<T, K | S>[] => {
  return [
    ...arr
      .reduce((accu, curr) => {
        const keyArr = groupByKeys.map((key) => curr[key]);
        const key = keyArr.join("-");
        const groupedSum =
          accu.get(key) ||
          Object.assign(
            {},
            Object.fromEntries(groupByKeys.map((key) => [key, curr[key]])),
            Object.fromEntries(sumKeys.map((key) => [key, 0]))
          );
        for (let key of sumKeys) {
          groupedSum[key] += curr[key];
        }
        return accu.set(key, groupedSum);
      }, new Map())
      .values(),
  ];
};

const arr = [
   { shape: "square", color: "red", available: 1, ordered: 1 },
   { shape: "square", color: "red", available: 2, ordered: 1 },
   { shape: "circle", color: "blue", available: 0, ordered: 3 },
   { shape: "square", color: "blue", available: 4, ordered: 4 },
 ];

const groupBySum = (arr, groupByKeys, sumKeys) => {
  return [
    ...arr
      .reduce((accu, curr) => {
        const keyArr = groupByKeys.map((key) => curr[key]);
        const key = keyArr.join("-");
        const groupedSum =
          accu.get(key) ||
          Object.assign(
            {},
            Object.fromEntries(groupByKeys.map((key) => [key, curr[key]])),
            Object.fromEntries(sumKeys.map((key) => [key, 0]))
          );
        for (let key of sumKeys) {
          groupedSum[key] += curr[key];
        }
        return accu.set(key, groupedSum);
      }, new Map())
      .values(),
  ];
};
console.log('groupBySum(arr, ["shape"], ["available"])')
console.log(groupBySum(arr, ["shape"], ["available"]))
console.log('\n\ngroupBySum(arr, ["color"], ["ordered"])')
console.log(groupBySum(arr, ["color"], ["ordered"]))
console.log('\n\ngroupBySum(arr, ["shape", "color"], ["available", "ordered"])')
console.log(groupBySum(arr, ["shape", "color"], ["available", "ordered"]))

groupBySum(arr, ["shape"], ["available"])
[
  { shape: 'square', available: 7 },
  { shape: 'circle', available: 0 }
]


groupBySum(arr, ["color"], ["ordered"])
[
  { color: 'red', ordered: 2 },
  { color: 'blue', ordered: 7 }
]


groupBySum(arr, ["shape", "color"], ["available", "ordered"])
[
  { shape: 'square', color: 'red', available: 3, ordered: 2 },
  { shape: 'circle', color: 'blue', available: 0, ordered: 3 },
  { shape: 'square', color: 'blue', available: 4, ordered: 4 }
]

groupBySum(arr, ["blah"], ["ordered"]);

Type '"blah"' is not assignable to type '"shape" | "ordered" | "color" | "available"'.ts(2322)

const ans = groupBySum(arr, ["shape"], ["ordered"])

Array<{ shape: string; ordered: number }>;