I\'m quite long description that I want to truncate using truncate helper. So i\'m using the:
truncate article.description, :length => 200, :omission => \
I encountered a similar situation and this did the trick. Try (line breaks for readability):
(truncate h(article.description),
:length => 200,
:omission => "... #{link_to('[more]',articles_path(article)}")
.html_safe
You can use h to ensure sanity of article description, and since you are setting the link_to to a path you know to not be something potentially nefarious, you can mark the resulting string as html_safe without concern.