This library wraps deep-diff#diff(). All the computed diffs are the same except for array element edits.

Usage

Just like the usage with deep-diff:

const diff = require('deep-diff-keep-element').diff;

const objLeft = {...};
const objRight = {...};

const result = diff(objLeft, objRight);

Installation

npm install deep-diff-keep-element --save

Why does this utility exist?

First, it's a proposal that illustrates what we needed.

For our auditing system we needed to persist the whole array element and not just the difference.

The object difference for

const objA = {array: [{a: 1, b:3, c:0}]};
const objB = {array: [{a: 2, b:4, c:0}]};

would look in the original deep-diff like:

[{
  kind: "E",
  lhs: 1,
  rhs: 2,
  path: ["array", 0, "a"]
}]

With this utility the result keeps the original and changed elements. It also has the kind as A and changes the structure a bit:

EDIT

[{
   kind: "A",
   path: ["array", 0],
   item: {
       kind: "E",
       path: ["a"],
       lhs: {a: 1, b:3, c:0},
       rhs: {a: 2, b:4, c:0}
   }
}]

DELETE

[{
    "kind": "A",
    "path": ["array", 0],
    "item": {
        "kind": "D",
        "path": ["a"],
        "lhs": {a: 1, b: 2},
        "rhs": {}
    }
}]

Tests

1. npm install
2. npm test