Analyse following RPM build log snippet. Describe contents accurately, without speculation or suggestions for resolution.            
Your analysis must be as concise as possible, while keeping relevant information intact.
Snippet: 
    error generating index.html: No such file or directory @ rb_sysopen - /usr/share/gems/gems/rdoc-6.8.0/lib/rdoc/generator/template/darkfish/_sidebar_toggle.rhtml (RDoc::Error)
File `/usr/share/gems/gems/rdoc-6.8.0/lib/rdoc/generator/template/darkfish/_sidebar_toggle.rhtml` is not present, causing error.