Do not send repository check mails when they are disabled

In case the repository checks are disabled, do not send the
mails. Otherwise it might send the same failures over and over again.

app/workers/admin_email_worker.rb

@@ -3,6 +3,12 @@ class AdminEmailWorker
   include CronjobQueue
 
   def perform
+    send_repository_check_mail if Gitlab::CurrentSettings.repository_checks_enabled
+  end
+
+  private
+
+  def send_repository_check_mail
     repository_check_failed_count = Project.where(last_repository_check_failed: true).count
     return if repository_check_failed_count.zero?
 

spec/workers/admin_email_worker_spec.rb

@@ -0,0 +1,41 @@
+require 'spec_helper'
+
+describe AdminEmailWorker do
+  subject(:worker) { described_class.new }
+
+  describe '.perform' do
+    it 'does not attempt to send repository check mail when they are disabled' do
+      stub_application_setting(repository_checks_enabled: false)
+
+      expect(worker).not_to receive(:send_repository_check_mail)
+
+      worker.perform
+    end
+
+    context 'repository_checks enabled' do
+      before do
+        stub_application_setting(repository_checks_enabled: true)
+      end
+
+      it 'checks if repository check mail should be sent' do
+        expect(worker).to receive(:send_repository_check_mail)
+
+        worker.perform
+      end
+
+      it 'does not send mail when there are no failed repos' do
+        expect(RepositoryCheckMailer).not_to receive(:notify)
+
+        worker.perform
+      end
+
+      it 'send mail when there is a failed repo' do
+        create(:project, last_repository_check_failed: true, last_repository_check_at: Date.yesterday)
+
+        expect(RepositoryCheckMailer).to receive(:notify).and_return(spy)
+
+        worker.perform
+      end
+    end
+  end
+end