prop-path-map.ts

prop-path-map.ts

type PropKey = string | number;
type PropValue = null | undefined | number | boolean | string | Date;

export function toPropPathMap(input: unknown) {
  const output = new Map<PropKey[], PropValue>();

  function traverse(v: unknown, keys: PropKey[]) {
    // prettier-ignore
    if (
      typeof v === "undefined" ||
      typeof v === "number" ||
      typeof v === "boolean" ||
      typeof v === "string" ||
      v === null ||
      v instanceof Date
    ) {
      output.set(keys, null);

    } else if (Array.isArray(v)) {
      for (let i = 0; i < v.length; i++) {
        traverse(v[i], [...keys, i]);
      }

    } else {
      tinyassert(typeof v === "object");
      for (const [k, inner] of Object.entries(v)) {
        traverse(inner, [...keys, k]);
      }
    }
  }

  traverse(input, []);
  return output;
}