TDiff
Description
Calculates the differences between two tree-like structures. Similar to Rubys built-in TSort module.
Features
- Provides the {TDiff} mixin.
- Provides the {TDiff::Unordered} mixin for unordered diffing.
- Allows custom node equality and traversal logic by overriding the {TDiff#tdiff_equal} and {TDiff#tdiff_each_child} methods.
- Implements the Longest Common Subsequence (LCS) algorithm.
Examples
Diff two HTML documents:
require 'nokogiri'
require 'tdiff'
class Nokogiri::XML::Node
include TDiff
def tdiff_equal(node)
if (self.text? && node.text?)
self.text == node.text
elsif (self.respond_to?(:root) && node.respond_to?(:root))
self.root.tdiff_equal(node.root)
elsif (self.respond_to?(:name) && node.respond_to?(:name))
self.name == node.name
else
false
end
end
def tdiff_each_child(node,&block)
node.children.each(&block)
end
end
doc1 = Nokogiri::HTML('<div><p>one</p> <p>three</p></div>')
doc2 = Nokogiri::HTML('<div><p>one</p> <p>two</p> <p>three</p></div>')
doc1.at('div').tdiff(doc2.at('div')) do |change,node|
puts "#{change} #{node.to_html}".ljust(30) + node.parent.path
endOutput
+ <p>one</p> /html/body/div
+ /html/body/div
<p>one</p> /html/body/div
/html/body/div
<p>three</p> /html/body/div
- one /html/body/div/p[1]
+ two /html/body/div/p[2]
three /html/body/div/p[2]
Requirements
- ruby >= 2.0.0
Install
$ gem install tdiffCopyright
See {file:LICENSE.txt} for details.