Merge branch 'fix/sm/32790-pipeline_schedules-pages-throwing-error-500' into 'master'

Follow-up from "Resolve "pipeline_schedules pages throwing error 500""

Closes #35345, #32790, and #34652

See merge request !12983

app/views/projects/pipeline_schedules/_pipeline_schedule.html.haml

@@ -4,7 +4,7 @@
       = pipeline_schedule.description
     %td.branch-name-cell
       = icon('code-fork')
-      - if pipeline_schedule.ref
+      - if pipeline_schedule.ref.present?
         = link_to pipeline_schedule.ref, project_ref_path(@project, pipeline_schedule.ref), class: "ref-name"
     %td
       - if pipeline_schedule.last_pipeline

changelogs/unreleased/fix-sm-32790-pipeline_schedules-pages-throwing-error-500.yml

@@ -0,0 +1,4 @@
+---
+title: Fix pipeline_schedules pages throwing error 500 (when ref is empty)
+merge_request: 12983
+author:

spec/features/projects/pipeline_schedules_spec.rb

@@ -70,6 +70,17 @@ feature 'Pipeline Schedules', :feature, js: true do
           expect(first('.branch-name-cell').text).to eq('')
         end
       end
+
+      context 'when ref is empty' do
+        before do
+          pipeline_schedule.update_attribute(:ref, '')
+          visit_pipelines_schedules
+        end
+
+        it 'shows a list of the pipeline schedules with empty ref column' do
+          expect(first('.branch-name-cell').text).to eq('')
+        end
+      end
     end
 
     describe 'POST /projects/pipeline_schedules/new' do
@@ -128,6 +139,19 @@ feature 'Pipeline Schedules', :feature, js: true do
           end
         end
       end
+
+      context 'when ref is empty' do
+        before do
+          pipeline_schedule.update_attribute(:ref, '')
+          edit_pipeline_schedule
+        end
+
+        it 'shows the pipeline schedule with default ref' do
+          page.within('.js-target-branch-dropdown') do
+            expect(first('.dropdown-toggle-text').text).to eq('master')
+          end
+        end
+      end
     end
 
     context 'when user creates a new pipeline schedule with variables' do