README.md

lodash-redux-immutability

Lean (just 24 lines of code!) immutable wrappers around lodash get/set/update/delete, especially helpful for redux reducers.

Install

npm install lodash-redux-immutability --save

Dependencies

lodash.clone;
lodash.get;
lodash.isempty;
lodash.isnumber;
lodash.isstring;
lodash.setwith;
lodash.unset;

Test coverage

✅ 100%

Gotchas

When setting/updating, passing a number (ie, 3) in your path will look for an array at index 3 , but passing a "string-number" (ie, '3') will look for an object with a key of '3'.
Source | Tests

API

updateIn(state:Object, path:Array<string|number>, valueToUpdate:Object)

Merges (spreads) valueToUpdate at path inside of state with the current value found at this path, creating any keys in path that do not exist, returning a new object where affected objects in the path have a new reference.

Source | Tests | Example:

import { updateIn } from 'lodash-redux-immutability';
const state = {
  stores: {
    '3': {
      name: 'three'
    '4': {
      name: 'four'
    }
  }
};
const storeThreeUpdates = { location: 'Third street' };
const newState = updateIn(state, ['stores', '3'], storeThreeUpdates);
newState.stores['3']; // { name: 'three', 'location: 'Third street' };
newState.stores === state.stores; // false
newState.stores['3'] === state.stores['3']; // false
newState.stores['4'] === state.stores['4']; // true

setIn(state:Object, path:Array<string|number>, valueToSet:any)

Replaces valueToSet at path inside of state, creating any keys in path that do not exist, returning a new object where affected objects in the path have a new reference.

Source | Tests | Example:

import { setIn } from 'lodash-redux-immutability';
const state = {
  stores: {
    '3': {
      name: 'three'
    }
    '4': {
      name: 'four'
    }
  }
};
const newState = setIn(state, ['stores', '3', 'name'], 'tres');
newState.stores['3']; // { name: 'tres' }
newState.stores === state.stores; // false
newState.stores['3'] === state.stores['3']; // false
newState.stores['4'] === state.stores['4']; // true

deleteIn(state:Object, path:Array<string|number>)

Deletes the value at path inside of state, returning a new object where affected objects in the path have a new reference.

Source | Tests | Example:

import { deleteIn } from 'lodash-redux-immutability';
const state = {
  '3': {
    name: 'three'
  },
  '4': {
    name: 'four'
  }
};
const newState = deleteIn(state, ['stores', '3'];
newState.stores['3']; // undefined
newState.stores === state.stores; // false
newState.stores['4'] === state.stores['4']; // true

getIn(state:Object, path:Array<string|number>, defaultValue?:any)

Get a value from an object by path. Returns the value, unless path is an empty [], in which case returns the original object

Source | Tests | Example:

import { getIn } from 'lodash-redux-immutability';
const state = {
  stores: {
    '3': {
      name: 'three'
    }
  }
};
const storeThreeName = getIn(state, ['stores', '3', 'name']); // 'three'
const entireState = getIn(state, []); // the entire 'state' object (this is what makes `getIn` different from the traditional `_.get`)

License

MIT