new_contents: # vim: set fileencoding=utf-8
  from mock import patch
  from unittest import TestCase
  
  from regulations.docket import sanitize_fields, Field
  
  
  class SanitizeFieldsTest(TestCase):
      def setUp(self):
          self.patch_document_fields = patch(
              'regulations.docket.get_document_fields')
          mock_object = self.patch_document_fields.start()
          mock_object.return_value = {
              "required_field": Field(10, True),
              "optional_field": Field(10, False),
          }
  
      def tearDown(self):
          self.patch_document_fields.stop()
  
      def test_valid_body(self):
          test_body = {
              "required_field": "Value 1",
              "optional_field": "Value 2"
          }
          valid, message = sanitize_fields(test_body)
          self.assertTrue(valid)
  
      def test_missing_optional_field(self):
          test_body = {
              "required_field": "Value 1"
          }
          valid, message = sanitize_fields(test_body)
          self.assertTrue(valid)
  
      def test_missing_required_field(self):
          test_body = {
              "optional_field": "Some value"
          }
          valid, message = sanitize_fields(test_body)
          self.assertFalse(valid)
          self.assertEqual("Field required_field is required", message)
  
      def test_extra_field(self):
          test_body = {
              "required_field": "Value 1",
              "extra_field": "Value 2"
          }
          valid, message = sanitize_fields(test_body)
          self.assertTrue(valid)
          self.assertTrue("extra_field removed", "extra_field" not in test_body)
  
      def test_field_too_long(self):
          test_body = {
              "required_field": "Value that exceeds 10 chars",
          }
          valid, message = sanitize_fields(test_body)
          self.assertFalse(valid)
          self.assertEqual("Field required_field exceeds expected length of 10",
                           message)
  
subject: Add tests for sanitize_fields