old_contents: from django.test import TestCase
  
  from nodeconductor_assembly_waldur.invoices.tasks import format_invoice_csv
  
  from .. import models
  from . import fixtures
  
  
  class TestReportFormatter(TestCase):
      def test_invoice_items_are_properly_formatted(self):
          fixture = fixtures.InvoiceFixture()
          package = fixture.openstack_package
          invoice = models.Invoice.objects.get(customer=package.tenant.service_project_link.project.customer)
          report = format_invoice_csv(invoice)
          self.assertEqual(2, len(report.splitlines()))
  
new_contents: from django.test import TestCase
  
  from nodeconductor_assembly_waldur.invoices.tasks import format_invoice_csv
  
  from .. import models
  from . import fixtures
  
  
  class TestReportFormatter(TestCase):
      def setUp(self):
          fixture = fixtures.InvoiceFixture()
          package = fixture.openstack_package
          invoice = models.Invoice.objects.get(customer=package.tenant.service_project_link.project.customer)
          self.invoice = invoice
  
      def test_invoice_items_are_properly_formatted(self):
          report = format_invoice_csv(self.invoice)
          lines = report.splitlines()
          self.assertEqual(2, len(lines))
  
          expected_header = 'customer_uuid;customer_name;project_uuid;project_name;' \
                            'invoice_uuid;invoice_number;invoice_year;invoice_month;' \
                            'invoice_date;due_date;invoice_price;invoice_tax;' \
                            'invoice_total;name;article_code;product_code;' \
                            'price;tax;total;daily_price;start;end;usage_days'
          self.assertEqual(lines[0], expected_header)
  
subject: Add unit test for report formatter [WAL-905]