Fix position validation error when editing stratified sortitions with imported participants (#23)

* Fix false positive position

* Update line too long

* Fix lint

Author: RubenBlazquez

app/forms/decidim/stratified_sortitions/admin/stratified_sortitions_form.rb

@@ -79,7 +79,9 @@ def validate_strata_attributes
 
             errors.add(:strata, :cannot_change_stratum_kind_with_sample_participants) if existing_stratum.kind != stratum_form.kind
 
-            errors.add(:strata, :cannot_change_stratum_position_with_sample_participants) if existing_stratum.position != stratum_form.position.to_i
+            if existing_stratum.position.present? && existing_stratum.position != stratum_form.position.to_i
+              errors.add(:strata, :cannot_change_stratum_position_with_sample_participants)
+            end
           end
         end
 
@@ -119,7 +121,9 @@ def validate_substrata_attributes(existing_stratum, stratum_form)
               errors.add(:strata, :cannot_change_substratum_range_with_sample_participants)
             end
 
-            errors.add(:strata, :cannot_change_substratum_position_with_sample_participants) if existing_substratum.position != substratum_form.position.to_i
+            if existing_substratum.position.present? && existing_substratum.position != substratum_form.position.to_i
+              errors.add(:strata, :cannot_change_substratum_position_with_sample_participants)
+            end
           end
         end
 

spec/forms/decidim/sortitions/admin/stratified_sortitions_form_spec.rb

@@ -227,6 +227,21 @@ module Admin
 
                 include_examples "blocks the change with error", "cannot_change_substratum_position_with_sample_participants"
               end
+
+              context "when substratum position is nil in DB and form sends a position" do
+                let!(:substratum) { create(:substratum, stratum:, name: { en: "18-25" }, value: "young", range: nil, position: nil, max_quota_percentage: "10") }
+                let(:stratum_params) { base_stratum_params.merge(substrata: { substratum.id.to_s => base_substratum_params.merge(position: 0) }) }
+
+                include_examples "allows the change"
+              end
+            end
+
+            context "when stratum position is nil in DB and form sends a position" do
+              let!(:stratum) { create(:stratum, stratified_sortition:, name: { en: "Age" }, kind: "value", position: nil) }
+              let!(:substratum) { create(:substratum, stratum:, name: { en: "18-25" }, value: "young", range: nil, position: 0, max_quota_percentage: "10") }
+              let(:stratum_params) { base_stratum_params.merge(position: 0) }
+
+              include_examples "allows the change"
             end
           end
         end