Handle incorrect setup of the question formatter

app/services/question_formatter/base_service.rb

@@ -58,7 +58,11 @@ def format_sub_question(sub_question)
 
     def format_by_type
       method = @question.class.model_exporter
-      send(method)
+      begin
+        send(method)
+      rescue => e
+        "Question type: #{question_type} requires a valid export format method"
+      end
     end
 
     private

spec/services/question_formatter/base_service_spec.rb

@@ -13,4 +13,17 @@
   it 'has the correct public methods' do
     expect(subject).to respond_to(:format_content)
   end
+
+  context 'when calling #format_content' do
+    describe 'when question model has no valid model_exporter method defined' do
+      before do
+        allow(question.class).to receive(:model_exporter).and_return('abc')
+        allow(subject).to receive(:divider_line).and_return("\n---\n\n")
+      end
+
+      it 'handles errors gracefully' do
+        expect(subject.format_content).to eq("Question type: Essay requires a valid export format method\n---\n\n")
+      end
+    end
+  end
 end