Rails 4: how to identify and format links, hashtags and mentions in model attributes? - css

Question

In my Rails 4 app, I have a Post model, with :copy and :short_copy as custom attributes (strings).
These attributes contain copies for social medias (Facebook, Twitter, Instagram, Pinterest, etc.).
I display the content of these attributes in my Posts#Show view.
Currently, URLs, #hashtags and #mentions are formatted like the rest of the text.
What I would like to do is to format them in a different fashion, for instance in another color or in bold.
I found the twitter-text gem, which seems to offer such features, but my problem is that I do NOT need — and do NOT want — to have these URLs, #hashtags and #mentions turn into real links.
Indeed, it looks like the twitter-text gem converts URLs, #hashtags and #mentions by default with Twitter::Autolink, as explained in this Stack Overflow question.
That's is not what I am looking for: I just want to update the style of my URLs, #hashtags and #mentions.
How can I do this in Ruby / Rails?
—————
UPDATE:
Following Wes Foster's answer, I implemented the following method in post.rb:
def highlight(string)
string.gsub!(/\S*#(\[[^\]]+\]|\S+)/, '<span class="highlight">\1</span>')
end
Then, I defined the following CSS class:
.highlight {
color: #337ab7;
}
Last, I implemented <%= highlight(post.copy) %> in the desired view.
I now get the following error:
ArgumentError
wrong number of arguments (1 for 2..3)
<td><%= highlight(post.copy) %></td>
What am I doing wrong?
—————

Answer 1

I'm sure each of the following regex patterns could be improved to match even more options, however, the following code works for me:
def highlight_url(str)
str.gsub!(/(https?:\/\/[\S]+)/, '[\1]')
end
def highlight_hashtag(str)
str.gsub!(/\S*#(\[[^\]]+\]|\S+)/, '[#\1]')
end
def highlight_mention(str)
str.gsub!(/\B(\#[a-z0-9_-]+)/i, '[\1]')
end
# Initial string
str = "Myself and #doggirl bought a new car: http://carpictures.com #nomoremoney"
# Pass through each
highlight_mention(str)
highlight_hashtag(str)
highlight_url(str)
puts str # > Myself and [#doggirl] bought a new car: [http://carpictures.com] [#nomoremoney]
In this example, I've wrapped the matches with brackets []. You should use a span tag and style it. Also, you can wrap all three gsub! into a single method for simplicity.
Updated for the asker's add-on error question
It looks like the error is references another method named highlight. Try changing the name of the method from highlight to new_highlight to see if that fixes the new problem.