Fix the merge notification email not being sent

app/mailers/emails/merge_requests.rb

@@ -29,11 +29,11 @@ module Emails
            subject: subject("#{@merge_request.title} (!#{@merge_request.iid})"))
     end
 
-    def merged_merge_request_email(recipient_id, merge_request_id)
+    def merged_merge_request_email(recipient_id, merge_request_id, updated_by_user_id)
       @merge_request = MergeRequest.find(merge_request_id)
       @project = @merge_request.project
       @target_url = project_merge_request_url(@project, @merge_request)
-      mail(from: sender(@merge_request.author_id_of_changes),
+      mail(from: sender(updated_by_user_id),
            to: recipient(recipient_id),
            subject: subject("#{@merge_request.title} (!#{@merge_request.iid})"))
     end

app/services/notification_service.rb

@@ -91,7 +91,7 @@ class NotificationService
     recipients = recipients.concat(project_watchers(merge_request.target_project)).uniq
 
     recipients.each do |recipient|
-      mailer.merged_merge_request_email(recipient.id, merge_request.id)
+      mailer.merged_merge_request_email(recipient.id, merge_request.id, merge_request.author_id_of_changes)
     end
   end
 

spec/mailers/notify_spec.rb

@@ -229,6 +229,7 @@ describe Notify do
       end
 
       context 'for merge requests' do
+        let(:merge_author) { create(:user) }
         let(:merge_request) { create(:merge_request, author: current_user, assignee: assignee, source_project: project, target_project: project) }
         let(:merge_request_with_description) { create(:merge_request, author: current_user, assignee: assignee, source_project: project, target_project: project, description: Faker::Lorem.sentence) }
 
@@ -288,7 +289,30 @@ describe Notify do
           it 'contains a link to the merge request' do
             should have_body_text /#{project_merge_request_path project, merge_request}/
           end
+        end
+
+        describe 'that are merged' do
+          subject { Notify.merged_merge_request_email(recipient.id, merge_request.id, merge_author.id) }
+
+          it_behaves_like 'a multiple recipients email'
+
+          it 'is sent as the merge author' do
+            sender = subject.header[:from].addrs[0]
+            sender.display_name.should eq(merge_author.name)
+            sender.address.should eq(gitlab_sender)
+          end
+
+          it 'has the correct subject' do
+            should have_subject /#{merge_request.title} \(!#{merge_request.iid}\)/
+          end
 
+          it 'contains the new status' do
+            should have_body_text /merged/i
+          end
+
+          it 'contains a link to the merge request' do
+            should have_body_text /#{project_merge_request_path project, merge_request}/
+          end
         end
       end
     end

spec/services/notification_service_spec.rb

@@ -233,15 +233,15 @@ describe NotificationService do
         should_email(@u_watcher.id)
         should_not_email(@u_participating.id)
         should_not_email(@u_disabled.id)
-        notification.merge_mr(merge_request)
+        notification.merge_mr(merge_request, @u_disabled)
       end
 
       def should_email(user_id)
-        Notify.should_receive(:merged_merge_request_email).with(user_id, merge_request.id)
+        Notify.should_receive(:merged_merge_request_email).with(user_id, merge_request.id, @u_disabled.id)
       end
 
       def should_not_email(user_id)
-        Notify.should_not_receive(:merged_merge_request_email).with(user_id, merge_request.id)
+        Notify.should_not_receive(:merged_merge_request_email).with(user_id, merge_request.id, @u_disabled.id)
       end
     end
   end