I did write some tests for both sides of the fence - for one the tests in WWW::Mechanize and WWW::Mechanize::Shell exercise and check the client side, and for the server side, there is some rudimentary idea in CGI::Wiki::Simple, test *52.t, which does a setup, run and teardown of a CGI script.

I haven't found any good frameworks to do end-to-end CGI testing, but CGI::Application allows you to easily redirect the output of the CGI. You will still have to set up all the environment variables though.

perl -MHTTP::Daemon -MHTTP::Response -MLWP::Simple -e ' ;    # The  
$d = new HTTP::Daemon and fork and getprint $d->url and exit;#spider
($c = $d->accept())->get_request(); $c->send_response( new   #in the
HTTP::Response(200,$_,$_,qq(Just another Perl hacker\n))); ' #  web
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