Fix duplicated endorsements

decidim-core/app/commands/decidim/endorse_resource.rb

@@ -31,6 +31,8 @@ def call
       else
         broadcast(:invalid)
       end
+    rescue ActiveRecord::RecordNotUnique
+      broadcast(:invalid)
     end
 
     private

decidim-core/app/commands/decidim/unendorse_resource.rb

@@ -31,7 +31,7 @@ def destroy_resource_endorsement
       query = if @current_group.present?
                 @resource.endorsements.where(decidim_user_group_id: @current_group&.id)
               else
-                @resource.endorsements.where(author: @current_user, decidim_user_group_id: nil)
+                @resource.endorsements.where(author: @current_user, decidim_user_group_id: 0)
               end
       query.destroy_all
     end

decidim-core/db/migrate/20231027142329_change_default_value_for_decidim_endorsements.rb

@@ -0,0 +1,11 @@
+# frozen_string_literal: true
+
+class ChangeDefaultValueForDecidimEndorsements < ActiveRecord::Migration[6.1]
+  def up
+    change_column_default :decidim_endorsements, :decidim_user_group_id, 0
+  end
+
+  def down
+    change_column_default :decidim_endorsements, :decidim_user_group_id, nil
+  end
+end

decidim-core/lib/decidim/endorsable.rb

@@ -21,7 +21,7 @@ def endorsed_by?(user, user_group = nil)
         if user_group
           endorsements.where(user_group:).any?
         else
-          endorsements.where(author: user, user_group: nil).any?
+          endorsements.where(author: user, user_group: 0).any?
         end
       end
     end

decidim-core/spec/models/decidim/endorsement_spec.rb

@@ -86,8 +86,8 @@ module Decidim
 
       it "sorts user_grup endorsements first and then by created_at" do
         expected_sorting = [
-          endorsement.id, other_endorsement2.id,
-          other_endorsement1.id
+          other_endorsement1.id, endorsement.id,
+          other_endorsement2.id,
         ]
         expect(resource.endorsements.for_listing.pluck(:id)).to eq(expected_sorting)
       end