Question

Given markup inside an HTML document that looks like this

<h3>test</h3>
<p>test</p>
<hr/>
<h3>test2</h3>
<p>test2</p>
<hr/>

I’d like to to produce this

<div>
  <h3>test</h3>
  <p>test</p>
</div>
<div>
  <h3>test2</h3>
  <p>test2</p>
</div>

What’s the most elegant way to do with with Nokogiri?

Answer 1

Edit: Reworked answer to be a bit cleaner.
Edit2: Small rewrite to shorten by two lines

require 'nokogiri'    
doc = Nokogiri::HTML <<ENDHTML
  <h3>test</h3>
  <p>test</p>
  <hr/>
  <h3>test2</h3>
  <p>test2</p>
  <hr/>
ENDHTML

body = doc.at_css('body')         # Created by parsing as HTML
kids = body.xpath('./*')          # Every child of the body
body.inner_html = ""              # Empty the body now that we have our nodes

div = (body << "<div>").first     # Create our first container in the body
kids.each do |node|               # For every child that was in the body...
  if node.name=='hr'              
    div = (body << '<div>').first # Create a new container for stuff
  else                            
    div << node                   # Move this into the last container
  end                             
end                               
div.remove unless div.child       # Get rid of a trailing, empty div

puts body.inner_html
#=> <div>
#=> <h3>test</h3>
#=> <p>test</p>
#=> </div>
#=> <div>
#=> <h3>test2</h3>
#=> <p>test2</p>
#=> </div>