obj-diff

I needed a way of calculating the changes between two arrays of objects with ease

Outputs an object with 3 properties: added, removed, unchanged

Note that the third parameter (the comparator) is not required - if not provided a default (a == b) is used

Example usage

var items = [{
  id: 1
}, {
  id: 2
}, {
  id: 3
}];

var from = [items[0], items[1]];
var to = [items[1], items[2]];

var result = require('obj-diff')(from, to, function(a, b) { return (a.id == b.id); });

console.log(result);

/*
  outputs:
  
  { 
    added: [ { id: 3 } ],
    removed: [ { id: 1 } ],
    unchanged: [ { id: 2 } ] 
  }
*/