Just to put my comment from the outdated diff here again :)
```
error(msg) if @source =~ /^\s*(require|load)\s+['"]nokogiri['"]/ and (@source.include?('Nokogiri::XML.parse') or @source.include?('Nokogiri::XML::Reader'))
```
or
```
error(msg) if @source.include?('Nokogiri::XML.parse') or @source.include?('Nokogiri::XML::Reader')
```
since there should be no nokogiri reference, if it's not required/loaded.