This might seem oddly self-serving, but you might look into the Differ gem.

http://github.com/pvande/differ

While not designed to diff HTML specifically, that's something that it
could most probably be set up to do.  Consider giving it a try.

(Full disclosure: Yeah, it's mine.)

On Fri, May 22, 2009 at 3:25 AM, Virendra Negi
<virendra.negi / paladion.net> wrote:
> Brian Candler wrote:
>> Virendra Negi wrote:
>>> from past few days iam trying to find out a gem that can compare the
>>> difference between two html file. i have tried to install
>>> myobie-htmldiff gem but the install didnt work out properly an it gave
>>> me error
>>> ERROR: could not find gem myobie-htmldiff locally or in a repository
>>
>> Looks like github hasn't built the gem. There was a bug which was
>> recently fixed which was preventing gems being built. You can ask the
>> author to bump the gem version to force a rebuild, or you can build and
>> install the gem yourself:
>>
>>  git clone git://github.com/myobie/htmldiff.git
>>  cd htmldiff
>>  gem build htmldiff.gemspec
>>  sudo gem install htmldiff-0.0.1.gem
>>
>> If you don't have git available, then instead of 'git clone' just
>> download a tar or zip of the project (click the 'download' link on the
>> github page)
>
> i followed your step but when iam trying to do require "htmldiff" its
> give me error like that says
>
> ' LoadError: no such file to load -- htmldiff'
> --
> Posted via http://www.ruby-forum.com/.
>
>