don't do @username expansion in user profile about section

most users are probably putting @username to mean a twitter profile,
not a link to a lobste.rs profile

app/models/story.rb

@@ -267,7 +267,7 @@ class Story < ActiveRecord::Base
   end
 
   def generated_markeddown_description
-    Markdowner.to_html(self.description, allow_images = true)
+    Markdowner.to_html(self.description, { :allow_images => true })
   end
 
   def description=(desc)

app/models/user.rb

@@ -116,7 +116,9 @@ class User < ActiveRecord::Base
   end
 
   def linkified_about
-    Markdowner.to_html(self.about)
+    # most users are probably mentioning "@username" to mean a twitter url, not
+    # a link to a lobste.rs profile
+    Markdowner.to_html(self.about, { :disable_profile_links => true })
   end
 
   def recent_threads(amount)

extras/markdowner.rb

@@ -1,28 +1,36 @@
 class Markdowner
-  def self.to_html(text, allow_images = false)
+  # opts[:allow_images] allows <img> tags
+  # opts[:disable_profile_links] disables @username -> /u/username links
+
+  def self.to_html(text, opts = {})
     if text.blank?
       return ""
-    else
-      html = RDiscount.new(text.to_s, *[ :smart, :autolink, :safelink,
-        :filter_styles, :filter_html ] + (allow_images ? [] : [ :no_image ])).
-        to_html
+    end
 
-      # change <h1> headings to just emphasis tags
-      html.gsub!(/<(\/)?h(\d)>/) {|_| "<#{$1}strong>" }
+    args = [ :smart, :autolink, :safelink, :filter_styles, :filter_html ]
+    if !opts[:allow_images]
+      args.push :no_image
+    end
 
-      # fix links that got the trailing punctuation appended to move it outside
-      # the link
-      html.gsub!(/<a ([^>]+)([\.\!\,])">([^>]+)([\.\!\,])<\/a>/) {|_|
-        if $2.to_s == $4.to_s
-          "<a #{$1}\">#{$3}</a>#{$2}"
-        else
-          _
-        end
-      }
+    html = RDiscount.new(text.to_s, *args).to_html
 
-      # make links have rel=nofollow
-      html.gsub!(/<a href/, "<a rel=\"nofollow\" href")
+    # change <h1> headings to just emphasis tags
+    html.gsub!(/<(\/)?h(\d)>/) {|_| "<#{$1}strong>" }
 
+    # fix links that got the trailing punctuation appended to move it outside
+    # the link
+    html.gsub!(/<a ([^>]+)([\.\!\,])">([^>]+)([\.\!\,])<\/a>/) {|_|
+      if $2.to_s == $4.to_s
+        "<a #{$1}\">#{$3}</a>#{$2}"
+      else
+        _
+      end
+    }
+
+    # make links have rel=nofollow
+    html.gsub!(/<a href/, "<a rel=\"nofollow\" href")
+
+    if !opts[:disable_profile_links]
       # make @username link to that user's profile
       html.gsub!(/\B\@([\w\-]+)/) do |u|
         if User.find_by_username(u[1 .. -1])
@@ -31,8 +39,8 @@ class Markdowner
           u
         end
       end
-
-      html
     end
+
+    html
   end
 end