diff-delta

Converts a generic-diff diff into a series of add/update/remove deltas.

Installation

$ npm install --save diff-delta

Example

var diff = require('generic-diff')
var delta = require('diff-delta')

var d = delta(diff('falafel dreams', 'fallacy means'))
console.log(d)

The above code logs the following:

[
  {
    "items": ["a", "f", "e"],
    "index": 3,
    "added": false,
    "removed": true
  },
  {
    "items": ["a", "c", "y"],
    "index": 4,
    "added": true,
    "removed": false
  },
  {
    "items": ["m"],
    "index": 8,
    "added": true,
    "removed": true
  },
  {
    "items": ["r"],
    "index": 9,
    "added": false,
    "removed": true
  },
  {
    "items": ["n"],
    "index": 11,
    "added": true,
    "removed": true
  }
]

Each item in the array represents a delta, with an index at which to apply the delta assuming all previous deltas have been applied. The above sequences of deltas can thus be interpreted as:

1. Start with the original string, falafel dreams
2. Remove 3 items, afe, starting at index 3: fall dreams
3. Add acy at index 4: fallacy dreams
4. Replace 1 item at index 8 with m: fallacy mreams
5. Remove 1 item, m, at index 9: fallacy meams
6. Replace 1 item at index 11 with n: fallacy means

License

MIT.