Expect API

Overview

Nightwatch provides a fluent BDD-style interface for performing assertions on elements, defined on the expect namespace on the main Nightwatch instance. It is based on the Chai Expect assertion library and provides a greater level of flexibility, also adding new capabilities over the classic assert interface.

It uses a chain-able language to construct assertions given an element specified by a css/xpath selector. A simple example looks like the following:

describe('expect example', function() {
  it('sample test', function (browser) {
    // start with identifying the element
    // and then assert the element is present
    browser.expect.element('#main').to.be.present;
    // or assert the element is visible
    browser.expect.element('#main').to.be.visible;
  });
}