piece_justificative_service: fix for missing order_place

In production some pieces justificatives don't have an order place.

In this case, insert the champs after the ones that have an order place.

app/services/pieces_justificatives_service.rb

@@ -33,12 +33,8 @@ class PiecesJustificativesService
   end
 
   def self.types_pj_as_types_de_champ(procedure)
-    last_champ = procedure.types_de_champ.last
-    if last_champ.present?
-      order_place = last_champ.order_place + 1
-    else
-      order_place = 0
-    end
+    max_order_place = procedure.types_de_champ.pluck(:order_place).compact.max || -1
+    order_place = max_order_place + 1
 
     types_de_champ = [
       TypeDeChamp.new(

spec/services/pieces_justificatives_service_spec.rb

@@ -112,11 +112,25 @@ describe PiecesJustificativesService do
         create(
           :procedure,
           types_de_piece_justificative: tpjs,
-          types_de_champ: [build(:type_de_champ, order_place: 0)]
+          types_de_champ: [build(:type_de_champ, order_place: 0), build(:type_de_champ, order_place: 1)]
         )
       end
 
       it 'generates a sequence of incrementing order_places that continues where the last type de champ left off' do
+        expect(subject.pluck(:order_place)).to contain_exactly(2, 3)
+      end
+    end
+
+    context 'with pre-existing champs without an order place' do
+      let(:procedure) do
+        create(
+          :procedure,
+          types_de_piece_justificative: tpjs,
+          types_de_champ: [build(:type_de_champ, order_place: 0), build(:type_de_champ, order_place: nil)]
+        )
+      end
+
+      it 'ignores champs without an order place' do
         expect(subject.pluck(:order_place)).to contain_exactly(1, 2)
       end
     end