tasks: delete dossiers without procedures

Fix #3279

spec/lib/tasks/deployment/20190117154829_delete_dossiers_without_procedure.rake_spec.rb

@@ -0,0 +1,42 @@
+describe '20190117154829_delete_dossiers_without_procedure.rake' do
+  let(:rake_task) { Rake::Task['after_party:delete_dossiers_without_procedure'] }
+
+  subject do
+    rake_task.invoke
+  end
+
+  after do
+    rake_task.reenable
+  end
+
+  context 'when the procedure of some dossiers has been deleted' do
+    let!(:procedure1) { create(:procedure_with_dossiers, dossiers_count: 2) }
+    let!(:procedure2) { create(:procedure_with_dossiers, :published, dossiers_count: 2) }
+    let!(:procedure3) { create(:procedure_with_dossiers, :published, dossiers_count: 2) }
+    let!(:procedure4) { create(:procedure_with_dossiers, :archived, dossiers_count: 2) }
+
+    let(:procedure_2_dossier_ids) { procedure2.dossiers.pluck(:id) }
+
+    before do
+      procedure_2_dossier_ids
+      procedure2.delete
+      expect(procedure_2_dossier_ids.count).to eq(2)
+      expect(Dossier.find_by(id: procedure_2_dossier_ids.first).procedure).to be nil
+      expect(Dossier.find_by(id: procedure_2_dossier_ids.second).procedure).to be nil
+    end
+
+    it 'destroy dossiers without an existing procedure' do
+      subject
+      expect(Dossier.unscoped.find_by(id: procedure_2_dossier_ids.first)).to be nil
+      expect(Dossier.unscoped.find_by(id: procedure_2_dossier_ids.last)).to be nil
+    end
+
+    it 'doesn’t destroy other dossiers' do
+      subject
+      expect(Dossier.all.count).to eq(6)
+      expect(procedure1.reload.dossiers.count).to eq(2)
+      expect(procedure3.reload.dossiers.count).to eq(2)
+      expect(procedure4.reload.dossiers.count).to eq(2)
+    end
+  end
+end