anchor.diff:        var data = JSON.decode(UTF8.decode(await response.body.first));
         expect(data['error']['message'], 'Missing parameter: \'offset\'');
       });
  -     */
   
       test('document', () async {
         var json = {'source': 'void main() {print("foo");}', 'offset': 17};
  
positive.code:         expect(response.status, 400);
       });
  
      /*
      test('complete', () async {
        var json = {'source': 'void main() {print("foo");}', 'offset': 1};
        var response = await _sendPostRequest('dartservices/v1/complete', json);
  
negative.code:       expect(data, {"info": {}});
      });
  
      test('document negative-test noSource', () async {
        var json = { 'offset': 12 };
        var response = await _sendPostRequest('dartservices/v1/document', json);
        expect(response.status, 400);
      });
  
      test('document negative-test noOffset', () async {
        var json = {'source': 'void main() {print("foo");}' };
        var response = await _sendPostRequest('dartservices/v1/document', json);
        expect(response.status, 400);
      });
    });
  }
  
  class MockCache implements ServerCache {
  