# nokogiri-diff

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* [Source](https://github.com/postmodern/nokogiri-diff)
* [Issues](https://github.com/postmodern/nokogiri-diff/issues)
* [Documentation](http://rubydoc.info/gems/nokogiri-diff/frames)

## Description

nokogiri-diff adds the ability to calculate the differences (added or
removed nodes) between two XML/HTML documents.

## Features

* Performs a breadth-first comparison between children nodes.
* Compares XML/HTML Elements, Attributes, Text nodes and DTD nodes.
* Allows calculating differences between documents, or just enumerating the
  added or removed nodes.

## Examples

Enumerate over the differences between two HTML documents:

```ruby
require 'nokogiri/diff'

doc1 = Nokogiri::HTML('<div><p>one</p> two </div>')
doc2 = Nokogiri::HTML('<div><p id="1">one</p> <p>three</p></div>')

doc1.diff(doc2) do |change,node|
  puts "#{change} #{node.to_html}".ljust(30) + node.parent.path
end

#   <div>
# <p>one</p> two </div> /
#   <p>one</p>                  /div
# -  two                        /div
# +                             /div
# + <p>three</p>                /div
# +  id="1"                     /div/p[1]
#   one                         /div/p
```

Only find the added nodes:

```ruby
doc1.diff(doc2, :added => true) do |change,node|
  puts node.to_html.ljust(30) + node.parent.path
end

#                               /div
# <p>three</p>                  /div
#  id="1"                       /div/p[1]
```

Only find the removed nodes:

```ruby
doc1.diff(doc2, :removed => true) do |change,node|
  puts node.to_html.ljust(30) + node.parent.path
end

#  two                          /div
```

## Requirements

* [ruby](http://www.ruby-lang.org/) >= 2.0.0
* [tdiff](http://github.com/postmodern/tdiff) ~> 0.4
* [nokogiri](http://nokogiri.rubyforge.org/) ~> 1.5

## Install

```shell
$ gem install nokogiri-diff
```

## License

See {file:LICENSE.txt} for details.