notification for note for merge request

app/mailers/notify.rb

@@ -30,6 +30,14 @@ class Notify < ActionMailer::Base
     @commit = @project.repo.commits(note.noteable_id).first
     mail(:to => @user.email, :subject => "gitlab | #{@note.project.name} ")
   end
+  
+  def note_merge_request_email(user, note)
+    @user = user
+    @note = note
+    @project = note.project
+    @merge_request = note.noteable
+    mail(:to => @user.email, :subject => "gitlab | #{@note.project.name} ")
+  end
 
   def note_issue_email(user, note)
     @user = user

app/models/mailer_observer.rb

@@ -34,8 +34,8 @@ class MailerObserver < ActiveRecord::Observer
           Notify.note_commit_email(u, note).deliver
         when "Issue" then
           Notify.note_issue_email(u, note).deliver
-        when "MergeRequest"
-          true # someone should write email notification
+        when "MergeRequest" then
+          Notify.note_merge_request_email(u, note).deliver
         when "Snippet"
           true
         else

app/views/notify/note_merge_request_email.html.haml

+%td.content{:align => "left", :style => "font-family: Helvetica, Arial, sans-serif; padding: 20px 0 0;", :valign => "top", :width => "600"}
+  %table{:border => "0", :cellpadding => "0", :cellspacing => "0", :style => "color: #717171; font: normal 11px Helvetica, Arial, sans-serif; margin: 0; padding: 0;", :width => "600"}
+    %tr
+      %td{:style => "font-size: 1px; line-height: 1px;", :width => "21"}
+      %td{:align => "left", :style => "padding: 20px 0 0;"}
+        %h2{:style => "color:#646464; font-weight: bold; margin: 0; padding: 0; line-height: 26px; font-size: 18px; font-family: Helvetica, Arial, sans-serif; "}
+          New comment for Merge Request
+          = link_to truncate(@merge_request.title, :length => 16), project_merge_request_url(@project, @merge_request, :anchor => "note_#{@note.id}")
+      %td{:style => "font-size: 1px; line-height: 1px;", :width => "21"}
+    %tr
+      %td{:style => "font-size: 1px; line-height: 1px;", :width => "21"}
+      %td{:style => "padding: 15px 0 15px;", :valign => "top"}
+        %p{:style => "color:#767676; font-weight: normal; margin: 0; padding: 0; line-height: 20px; font-size: 12px;font-family: Helvetica, Arial, sans-serif; "}
+          %a{:href => "#", :style => "color: #0eb6ce; text-decoration: none;"} #{@note.author.name}
+          left next message:
+        %br
+          %table{:border => "0", :cellpadding => "0", :cellspacing => "0", :width => "558"}
+            %tr
+              %td{:valign => "top"}
+                %cite{:style => "color:#767676; font-weight: normal; margin: 0; padding: 0; line-height: 20px; font-size: 12px;font-family: Helvetica, Arial, sans-serif; "}
+                  = @note.note
+      %td{:style => "font-size: 1px; line-height: 1px;", :width => "21"}
+