Add new notifications for issue move action

[ci skip]

app/mailers/emails/issues.rb

@@ -36,6 +36,14 @@ module Emails
       mail_answer_thread(@issue, issue_thread_options(updated_by_user_id, recipient_id))
     end
 
+    def issue_moved_email(recipient, issue, new_issue, updated_by_user)
+      setup_issue_mail(issue.id, recipient.id)
+
+      @new_issue = new_issue
+      @new_project = new_issue.project
+      mail_answer_thread(issue, issue_thread_options(updated_by_user.id, recipient.id))
+    end
+
     private
 
     def setup_issue_mail(issue_id, recipient_id)

app/services/issues/move_service.rb

@@ -10,13 +10,17 @@ module Issues
       if new_project_id
         @project_new = Project.find(new_project_id)
       end
+
+      if @project_new == @project_old
+        raise StandardError, 'Cannot move issue to project it originates from!'
+      end
     end
 
     def execute
       return unless move?
 
-      # Using trasaction because of a high footprint on
-      # rewriting notes (unfolding references)
+      # Using trasaction because of a high resources footprint
+      # on rewriting notes (unfolding references)
       #
       ActiveRecord::Base.transaction do
         # New issue tasks
@@ -99,6 +103,7 @@ module Issues
     end
 
     def notify_participants
+      notification_service.issue_moved(@issue_old, @issue_new, @current_user)
     end
   end
 end

app/services/notification_service.rb

@@ -236,6 +236,16 @@ class NotificationService
     end
   end
 
+  def issue_moved(issue, new_issue, current_user)
+    recipients = build_recipients(issue, issue.project, current_user)
+
+    recipients.map do |recipient|
+      email = mailer.issue_moved_email(recipient, issue, new_issue, current_user)
+      email.deliver_later
+      email
+    end
+  end
+
   protected
 
   # Get project users with WATCH notification level

app/views/notify/issue_moved_email.html.haml

@@ -0,0 +1,6 @@
+%p
+  Issue was moved to another project.
+%p
+  New issue:
+  = link_to namespace_project_issue_url(@new_project.namespace, @new_project, @new_issue) do
+    = @new_issue.title

app/views/notify/issue_moved_email.text.erb

@@ -0,0 +1,4 @@
+Issue was moved to another project.
+
+New issue location:
+<%= namespace_project_issue_url(@new_project.namespace, @new_project, @new_issue) %>

spec/mailers/notify_spec.rb

@@ -158,6 +158,33 @@ describe Notify do
             is_expected.to have_body_text /#{namespace_project_issue_path project.namespace, project, issue}/
           end
         end
+
+        describe 'moved to another project' do
+          let(:new_issue) { create(:issue) }
+          subject { Notify.issue_moved_email(recipient, issue, new_issue, current_user) }
+
+          it_behaves_like 'an answer to an existing thread', 'issue'
+          it_behaves_like 'it should show Gmail Actions View Issue link'
+          it_behaves_like 'an unsubscribeable thread'
+
+          it 'contains description about action taken' do
+            is_expected.to have_body_text 'Issue was moved to another project'
+          end
+
+          it 'has the correct subject' do
+            is_expected.to have_subject /#{issue.title} \(##{issue.iid}\)/i
+          end
+
+          it 'contains link to new issue' do
+            new_issue_url = namespace_project_issue_path(new_issue.project.namespace,
+                                                         new_issue.project, new_issue)
+            is_expected.to have_body_text new_issue_url
+          end
+
+          it 'contains a link to the original issue' do
+            is_expected.to have_body_text /#{namespace_project_issue_path project.namespace, project, issue}/
+          end
+        end
       end
 
       context 'for merge requests' do

spec/services/issues/move_service_spec.rb

@@ -55,7 +55,7 @@ describe Issues::MoveService, services: true do
         end
 
         it 'rewrites issue description' do
-          expect(new_issue.description).to include description
+          expect(new_issue.description).to eq description
         end
 
         it 'adds system note to old issue at the end' do