Check message presence in EE::RunnersHelper

Add missing specs for EE::RunnersHelper

Add changelog file

changelogs/unreleased/32156-fix-ci_usage_warning_message-message-builder.yml

+---
+title: Prevent the user from seeing an invalid "Purchase more minutes" prompt.
+merge_request: 16979
+author:
+type: fixed

ee/app/helpers/ee/runners_helper.rb

@@ -4,7 +4,7 @@ module EE
     def ci_usage_warning_message(namespace, project)
       message = [ci_usage_base_message(namespace)]
 
-      return unless message
+      return unless message.any?
 
       if ::Gitlab.com? && can?(current_user, :admin_project, project)
         message << purchase_shared_runner_minutes_link

ee/spec/helpers/ee/runners_helper_spec.rb

@@ -29,8 +29,8 @@ describe EE::RunnersHelper do
     context 'when CI minutes quota is above the warning limits' do
       let(:minutes_used) { 40 }
 
-      it 'does not return a message' do
-        expect(subject).to be_empty
+      it 'returns nil' do
+        expect(subject).to be_nil
       end
     end
 
@@ -39,6 +39,16 @@ describe EE::RunnersHelper do
         allow(helper).to receive(:can?).with(user, :admin_project, project) { true }
       end
 
+      context 'when base message is not present' do
+        before do
+          allow(helper).to receive(:ci_usage_base_message).with(namespace).and_return(nil)
+        end
+
+        it 'returns nil' do
+          expect(subject).to be_nil
+        end
+      end
+
       context 'when usage has reached first level of notification' do
         before do
           namespace.update_attribute(:last_ci_minutes_usage_notification_level, 50)
@@ -61,6 +71,16 @@ describe EE::RunnersHelper do
     end
 
     context 'when current user is not an owner' do
+      context 'when base message is not present' do
+        before do
+          allow(helper).to receive(:ci_usage_base_message).with(namespace).and_return(nil)
+        end
+
+        it 'returns nil' do
+          expect(subject).to be_nil
+        end
+      end
+
       context 'when usage has reached first level of notification' do
         before do
           namespace.update_attribute(:last_ci_minutes_usage_notification_level, 50)