immutable version of lodash/set

setIn.js

// https://github.com/lodash/lodash/issues/1696
import {clone, setWith, curry} from 'lodash/fp';

// export const setIn = curry((path, value, obj) =>
//   setWith(clone, path, value, clone(obj)),
// );
export const setIn = curry((obj, path, value) =>
  setWith(clone, path, value, clone(obj)),
);

// https://github.com/lodash/lodash/issues/1696#issuecomment-353016126
// f you're using TypeScript, you should consider utilizing some standalone typing-aware "immutable set" library,
// like monolite(https://github.com/kube/monolite) or immutable-assign(https://github.com/engineforce/ImmutableAssign).


// ! 上面的 setIn 会有问题：在遇到 setIn({ a: { b: 1, c: null }, d: "xxx" }, 'a.c.e', 2) => 对象未发生变化，即它无法影响 null
// 于是自己写了一个 setpath
export const setpath = (obj, path, value) => {
  const paths = path.split(/[\.\[\]\'\"]/g).map(s => parseInt(s) || s.trim()).filter(v => v!=='');
  function set(obj, paths, value) {
    if (paths.length === 0) {
      return value;
    }
    if (paths.length === 1) {
      const paths_0 = paths[0];
      if (paths_0 > -1) {
        const clone = (obj || []).slice();
        clone[paths_0] = value;
        return clone;
      }
      return Object.assign({}, obj, { [paths_0 + '']: value });
    }
    const tail = set(get(obj, paths.slice(0, -1)), paths.slice(-1), value);
    return set(obj, paths.slice(0, -1), tail);
  }
  return set(obj, paths, value);
}