Merge cross-reference refactoring with EE code

app/services/system_note_service.rb

@@ -167,10 +167,8 @@ class SystemNoteService
     if noteable.is_a?(ExternalIssue)
       noteable.project.issues_tracker.create_cross_reference_note(noteable, mentioner, author)
     else
-      create(note_options)
+      create_note(note_options)
     end
-
-    create_note(note_options)
   end
 
   def self.cross_reference?(note_text)

spec/services/system_note_service_spec.rb

@@ -343,4 +343,68 @@ describe SystemNoteService do
       end
     end
   end
+
+  include JiraServiceHelper
+
+  describe 'JIRA integration' do
+    let(:project)    { create(:project) }
+    let(:author)     { create(:user) }
+    let(:issue)      { create(:issue, project: project) }
+    let(:mergereq)   { create(:merge_request, :simple, target_project: project, source_project: project) }
+    let(:jira_issue) { JiraIssue.new("JIRA-1", project)}
+    let(:jira_tracker) { project.create_jira_service if project.jira_service.nil? }
+    let(:commit)     { project.commit }
+
+    context 'in JIRA issue tracker' do
+      before do
+        jira_service_settings
+        WebMock.stub_request(:post, jira_api_comment_url)
+      end
+
+      after do
+        jira_tracker.destroy!
+      end
+
+      describe "new reference" do
+        before do
+          WebMock.stub_request(:get, jira_api_comment_url).
+            to_return(:body => jira_issue_comments)
+        end
+
+        subject { Note.create_cross_reference_note(jira_issue, commit, author) }
+
+        it { is_expected.to eq(jira_status_message) }
+      end
+
+      describe "existing reference" do
+        before do
+          message = "[#{author.name}|http://localhost/u/#{author.username}] mentioned this issue in [a commit of #{project.path_with_namespace}|http://localhost/#{project.path_with_namespace}/commit/#{commit.id}]."
+          WebMock.stub_request(:get, jira_api_comment_url).
+            to_return(:body => "{\"comments\":[{\"body\":\"#{message}\"}]}")
+        end
+
+        subject { Note.create_cross_reference_note(jira_issue, commit, author) }
+        it { is_expected.not_to eq(jira_status_message) }
+      end
+    end
+
+    context 'issue from an issue' do
+      context 'in JIRA issue tracker' do
+        before do
+          jira_service_settings
+          WebMock.stub_request(:post, jira_api_comment_url)
+          WebMock.stub_request(:get, jira_api_comment_url).
+            to_return(:body => jira_issue_comments)
+        end
+
+        after do
+          jira_tracker.destroy!
+        end
+
+        subject { Note.create_cross_reference_note(jira_issue, issue, author) }
+
+        it { is_expected.to eq(jira_status_message) }
+      end
+    end
+  end
 end