[40027] Delete attribute help text when custom field destroyed

https://community.openproject.org/work_packages/40027

app/models/custom_field.rb

@@ -72,6 +72,7 @@ class CustomField < ApplicationRecord
                          unless: Proc.new { |cf| cf.max_length.blank? }
 
   before_validation :check_searchability
+  after_destroy :destroy_help_text
 
   # make sure int, float, date, and bool are not searchable
   def check_searchability
@@ -323,4 +324,10 @@ class CustomField < ApplicationRecord
       .sort
       .map { |u| [u.name, u.id.to_s] }
   end
+
+  def destroy_help_text
+    AttributeHelpText
+      .where(attribute_name: "custom_field_#{id}")
+      .destroy_all
+  end
 end

db/migrate/20211117195121_remove_destroyed_help_texts.rb

@@ -0,0 +1,16 @@
+class RemoveDestroyedHelpTexts < ActiveRecord::Migration[6.1]
+  def up
+    custom_field_ids = CustomField
+      .pluck(:id)
+      .map { |id| "custom_field_#{id}"}
+
+    AttributeHelpText
+      .where("attribute_name LIKE 'custom_field_%'")
+      .where.not(attribute_name: custom_field_ids)
+      .destroy_all
+  end
+
+  def down
+    # Nothing to do
+  end
+end

spec/models/attribute_help_text/work_package_spec.rb

@@ -29,6 +29,18 @@
 require 'spec_helper'
 
 describe AttributeHelpText::WorkPackage, type: :model do
+  def create_cf_help_text(custom_field)
+    # Need to clear the request store after every creation as the available attributes are cached
+    RequestStore.clear!
+    FactoryBot.create(:work_package_help_text, attribute_name: "custom_field_#{custom_field.id}")
+  end
+
+  let(:wp_custom_field) { FactoryBot.create :text_wp_custom_field }
+
+  let(:cf_instance) do
+    create_cf_help_text(wp_custom_field)
+  end
+
   it_behaves_like 'acts_as_attachable included' do
     let(:model_instance) { FactoryBot.create(:work_package_help_text) }
     let(:project) { FactoryBot.create(:project) }
@@ -61,17 +73,6 @@ describe AttributeHelpText::WorkPackage, type: :model do
     let(:permission) { [] }
     let(:static_instance) { FactoryBot.create :work_package_help_text, attribute_name: 'project' }
 
-    def create_cf_help_text(custom_field)
-      # Need to clear the request store after every creation as the available attributes are cached
-      RequestStore.clear!
-      FactoryBot.create(:work_package_help_text, attribute_name: "custom_field_#{custom_field.id}")
-    end
-
-    let(:cf_instance) do
-      custom_field = FactoryBot.create :text_wp_custom_field
-      create_cf_help_text(custom_field)
-    end
-
     subject { FactoryBot.build :work_package_help_text }
 
     before do
@@ -204,4 +205,17 @@ describe AttributeHelpText::WorkPackage, type: :model do
       expect(subject.type_caption).to eq I18n.t(:label_work_package)
     end
   end
+
+  describe 'destroy' do
+    context 'when the custom field is destroyed' do
+      before do
+        cf_instance
+        wp_custom_field.destroy
+      end
+
+      it 'also destroys the instance' do
+        expect { cf_instance.reload }.to raise_error(ActiveRecord::RecordNotFound)
+      end
+    end
+  end
 end