dossiers: allow auto upload of attachments

spec/controllers/champs/piece_justificative_controller_spec.rb

@@ -0,0 +1,65 @@
+describe Champs::PieceJustificativeController, type: :controller do
+  let(:user) { create(:user) }
+  let(:procedure) { create(:procedure, :published, :with_piece_justificative) }
+  let(:dossier) { create(:dossier, user: user, procedure: procedure) }
+  let(:champ) { dossier.champs.first }
+
+  describe '#update' do
+    render_views
+    before { sign_in user }
+
+    subject do
+      put :update, params: {
+        position: '1',
+        champ_id: champ.id,
+        blob_signed_id: file
+      }, format: 'js'
+    end
+
+    context 'when the file is valid' do
+      let(:file) { Rack::Test::UploadedFile.new('spec/fixtures/files/piece_justificative_0.pdf', 'application/pdf') }
+
+      it 'attach the file' do
+        subject
+        champ.reload
+        expect(champ.piece_justificative_file.attached?).to be true
+        expect(champ.piece_justificative_file.filename).to eq('piece_justificative_0.pdf')
+      end
+
+      it 'renders the attachment template as Javascript' do
+        subject
+        expect(response.status).to eq(200)
+        expect(response.body).to include("editable-champ[data-champ-id=\"#{champ.id}\"]")
+      end
+    end
+
+    context 'when the file is invalid' do
+      let(:file) { Rack::Test::UploadedFile.new('spec/fixtures/files/invalid_file_format.json', 'application/json') }
+
+      # TODO: for now there are no validators on the champ piece_justificative_file,
+      # so we have to mock a failing validation.
+      # Once the validators will be enabled, remove those mocks, and let the usual
+      # validation fail naturally.
+      #
+      # See https://github.com/betagouv/demarches-simplifiees.fr/issues/4926
+      before do
+        champ
+        expect_any_instance_of(Champs::PieceJustificativeChamp).to receive(:save).and_return(false)
+        expect_any_instance_of(Champs::PieceJustificativeChamp).to receive(:errors)
+          .and_return(double(full_messages: ['La pièce justificative n’est pas d’un type accepté']))
+      end
+
+      it 'doesn’t attach the file' do
+        subject
+        expect(champ.reload.piece_justificative_file.attached?).to be false
+      end
+
+      it 'renders an error' do
+        subject
+        expect(response.status).to eq(422)
+        expect(response.header['Content-Type']).to include('application/json')
+        expect(JSON.parse(response.body)).to eq({ 'errors' => ['La pièce justificative n’est pas d’un type accepté'] })
+      end
+    end
+  end
+end