In order to view full side-by-side diffs over the web interface, you must use the gitweb_sonic template. First create a folder called sonichgv2m102 in the htdocs folder (assuming you have apache running). Copy over the files in the sonichgv2m102/static folder to this newly created directory. Then modify the HGRC file of the repo to include:
[extensions] sonic=/path/to/sonichgv2m102/hgext/sonic.py sonicweb=/path/to/sonichgv2m102/hgext/sonicweb.py
[web] templates=/path/to/sonichgv2m102/templates style=gitweb_sonic staticurl=http://yourserver.com/sonichgv2m102 encoding=UTF-8
Note if you have python pygments installed and use the highlight extension you can even view the full diffs with highlight by enabling sonicwebhighlight in your HGRC file:
[extensions] sonic=/path/to/sonichgv2m102/hgext/sonic.py sonicweb=/path/to/sonichgv2m102/hgext/sonicweb.py hgext.highlight= sonicwebhighlight=/path/to/sonichgv2m102/hgext/sonichighlight.py
[web] templates=/path/to/sonichgv2m102/templates style=gitweb_sonic staticurl=http://yourserver.com/sonichgv2m102 encoding=UTF-8 pygments_style=default
Now if you go to the repo web UI and click on a changeset link you will see the fulldiff link for files next to the diff link. The fulldiff link appears where-ever the regular diff link appears. Check out the filelog page to see more use of fulldiff.