Linkify message:// URLs in notes. Those links are used by Mail.app on

Mac OS X to link to a mail message by message id.

app/helpers/todos_helper.rb

@@ -325,4 +325,28 @@ module TodosHelper
     return entries.map{|e| e.specification()}.join("\n") rescue ''
   end
 
+  AUTO_LINK_MESSAGE_RE = %r{message://<[^>]+>} unless const_defined?(:AUTO_LINK_MESSAGE_RE)
+
+  # Converts message:// links to href. This URL scheme is used on Mac OS X
+  # to link to a mail message in Mail.app.
+  def auto_link_message(text)
+    text.gsub(AUTO_LINK_MESSAGE_RE) do
+      href = $&
+      left, right = $`, $'
+      # detect already linked URLs and URLs in the middle of a tag
+      if left =~ /<[^>]+$/ && right =~ /^[^>]*>/
+        # do not change string; URL is alreay linked
+        href
+      else
+        content_tag(:a, h(href), :href => h(href))
+      end
+    end
+  end
+
+  def format_note(note)
+    note = auto_link_message(note)
+    note = auto_link(note)
+    note = markdown(note)
+    note = sanitize(note)
+  end
 end

app/views/notes/_notes.rhtml

@@ -2,7 +2,7 @@
 <div id="<%= dom_id(note, 'container') %>">
   <h2><%= link_to("Note #{note.id}", note_path(note), :title => "Show note #{note.id}" ) %></h2>
   <div class="project_notes" id="<%= dom_id(note) %>">
-    <%= sanitize(markdown(auto_link(note.body))) %>
+    <%= format_note(note.body) %>
 
     <div class="note_footer">
       <%= link_to_remote( 

app/views/todos/_toggle_notes.rhtml

@@ -1,5 +1,5 @@
 <%= link_to(image_tag( 'blank.png', :width=>'16', :height=>'16', :border=>'0' ), "#", {:class => 'show_notes', :title => 'Show notes'}) %>
 
 <div class="todo_notes" id="<%= dom_id(item, 'notes') %>" style="display:none">
-  <%= sanitize(markdown( auto_link(item.notes)) ) %>
+  <%= format_note(item.notes) %>
 </div>

config/environment.rb

@@ -58,7 +58,7 @@ Rails::Initializer.run do |config|
   # allow other protocols in urls for sanitzer. Add to your liking, for example
   # config.action_view.sanitized_allowed_protocols = 'onenote', 'blah', 'proto'
   # to enable "link":onenote://... or "link":blah://... hyperlinks
-  config.action_view.sanitized_allowed_protocols = 'onenote'
+  config.action_view.sanitized_allowed_protocols = 'onenote', 'message'
 
   # See Rails::Configuration for more options
 end

test/functional/todos_controller_test.rb

@@ -510,4 +510,44 @@ class TodosControllerTest < ActionController::TestCase
     assert_select("a[href=#{url}]")
   end
 
+  def test_format_note_normal
+    login_as(:admin_user)
+    todo = users(:admin_user).todos.first
+    todo.notes = "A normal description."
+    todo.save!
+    get :index
+    assert_select("div#notes_todo_#{todo.id}", "A normal description.")
+  end
+
+  def test_format_note_markdown
+    login_as(:admin_user)
+    todo = users(:admin_user).todos.first
+    todo.notes = "A *bold description*."
+    todo.save!
+    get :index
+    assert_select("div#notes_todo_#{todo.id}", "A bold description.")
+    assert_select("div#notes_todo_#{todo.id} strong", "bold description")
+  end
+
+  def test_format_note_link
+    login_as(:admin_user)
+    todo = users(:admin_user).todos.first
+    todo.notes = "A link to http://github.com/."
+    todo.save!
+    get :index
+    assert_select("div#notes_todo_#{todo.id}", 'A link to http://github.com/.')
+    assert_select("div#notes_todo_#{todo.id} a[href=http://github.com/]", 'http://github.com/')
+  end
+
+  def test_format_note_link_message
+    login_as(:admin_user)
+    todo = users(:admin_user).todos.first
+    todo.notes = "A Mail.app message://<ABCDEF-GHADB-123455-FOO-BAR@example.com> link"
+    todo.save!
+    get :index
+    # puts css_select("div#notes_todo_#{todo.id}")
+    assert_select("div#notes_todo_#{todo.id}", 'A Mail.app message://&lt;ABCDEF-GHADB-123455-FOO-BAR@example.com&gt; link')
+    assert_select("div#notes_todo_#{todo.id} a", 'message://&lt;ABCDEF-GHADB-123455-FOO-BAR@example.com&gt;')
+    assert_select("div#notes_todo_#{todo.id} a[href=message://&lt;ABCDEF-GHADB-123455-FOO-BAR@example.com&gt;]", 'message://&lt;ABCDEF-GHADB-123455-FOO-BAR@example.com&gt;')
+  end
 end