t(ajax.activeRequests.length).to.be.eql(1);
                resolve()
              } catch (e) {
                reject(e);
              }
            });

            ajax.handleas = 'text';
            ajax.params = { foo: 'bar' };
            ajax.headers = { 'X-Foo': 'Bar' };
          });
        });

        test('automatically generates new request when a sub-property of params is changed', function(done) {
          ajax.addEventListener('request', function() {
            server.respond();
      