jotai/immer.js

'use strict';

Object.defineProperty(exports, '__esModule', { value: true });

var immer = require('immer');
var jotai = require('jotai');
var react = require('react');

function atomWithImmer(initialValue) {
  var anAtom = jotai.atom(initialValue, function (get, set, fn) {
    return set(anAtom, immer.produce(get(anAtom), function (draft) {
      return fn(draft);
    }));
  });
  return anAtom;
}

function useImmerAtom(anAtom) {
  var _useAtom = jotai.useAtom(anAtom),
      state = _useAtom[0],
      setState = _useAtom[1];

  var setStateWithImmer = react.useCallback(function (fn) {
    setState(immer.produce(function (draft) {
      return fn(draft);
    }));
  }, [setState]);
  return [state, setStateWithImmer];
}

var getWeakCacheItem = function getWeakCacheItem(cache, deps) {
  var dep = deps[0],
      rest = deps.slice(1);
  var entry = cache.get(dep);

  if (!entry) {
    return;
  }

  if (!rest.length) {
    return entry[1];
  }

  return getWeakCacheItem(entry[0], rest);
};
var setWeakCacheItem = function setWeakCacheItem(cache, deps, item) {
  var dep = deps[0],
      rest = deps.slice(1);
  var entry = cache.get(dep);

  if (!entry) {
    entry = [new WeakMap()];
    cache.set(dep, entry);
  }

  if (!rest.length) {
    entry[1] = item;
    return;
  }

  setWeakCacheItem(entry[0], rest, item);
};

var withImmerCache = new WeakMap();
function withImmer(anAtom) {
  var deps = [anAtom];
  var cachedAtom = getWeakCacheItem(withImmerCache, deps);

  if (cachedAtom) {
    return cachedAtom;
  }

  var derivedAtom = jotai.atom(function (get) {
    return get(anAtom);
  }, function (get, set, fn) {
    return set(anAtom, immer.produce(get(anAtom), function (draft) {
      return fn(draft);
    }));
  });
  derivedAtom.scope = anAtom.scope;
  setWeakCacheItem(withImmerCache, deps, derivedAtom);
  return derivedAtom;
}

exports.atomWithImmer = atomWithImmer;
exports.useImmerAtom = useImmerAtom;
exports.withImmer = withImmer;