Implementing a test for the new helper

spec/helpers/index_helper_spec.rb

@@ -22,6 +22,8 @@ class TestingHelper
   end
 
   describe '#index_masonry_document_label' do
+    subject(:output) { helper.index_masonry_document_label(document) }
+
     let(:label) { 'title' }
 
     before do
@@ -30,6 +32,17 @@ class TestingHelper
       allow(index_presenter).to receive(:label).and_return(label)
     end
 
+    it 'retrieves the label using the title' do
+      expect(output).to eq 'title'
+    end
+
+    context 'when multiple titles exist' do
+      let(:label) { ['title1', 'title2'] }
+
+      it 'retrieves the label using only the first title' do
+        expect(output).to eq 'title1'
+      end
+    end
   end
 
   describe '#render_index_document' do