nightwatch/lib/api/client-commands/setDeviceDimensions.js

Easy to use Node.js based end-to-end testing solution for web applications using the W3C WebDriver API.

const ClientCommand = require('./_base-command.js');
const {Logger} = require('../../utils');

/**
 * Override device mode/dimensions. Call without any arguments to reset the device dimensions back to original.
 *
 * @example
 *  describe('modify device dimensions', function() {
 *    it('modifies the device dimensions and then resets it', function() {
 *      browser
 *        .setDeviceDimensions({
 *          width: 400,
 *          height: 600,
 *          deviceScaleFactor: 50,
 *          mobile: true
 *        })
 *        .navigateTo('https://www.google.com')
 *        .pause(1000)
 *        .setDeviceDimensions()  // resets the device dimensions
 *        .navigateTo('https://www.google.com')
 *        .pause(1000);
 *    });
 *  });
 *
 * @method setDeviceDimensions
 * @syntax .setDeviceDimensions({width, height, deviceScaleFactor, mobile}, [callback])
 * @param {object} [metrics] Device metrics to set. Metric defaults to original if not set.
 * @param {function} [callback] Callback function to be called when the command finishes.
 * @api protocol.cdp
 * @since 2.2.0
 * @moreinfo nightwatchjs.org/guide/mobile-web-testing/override-device-dimensions.html
 */
class SetDeviceDimensions extends ClientCommand {
  static get isTraceable() {
    return true;
  }

  performAction(callback) {

    if (!this.api.isChrome()  && !this.api.isEdge()) {
      const error =  new Error('The command .setDeviceDimensions() is only supported in Chrome and Edge drivers');
      Logger.error(error);

      return callback(error);
    }

    // The default values below disables the override for that property (if a user
    // has not set a property, they'd want that property to not be overridden).
    const {width = 0, height = 0, deviceScaleFactor = 0, mobile = false} = this.metrics;
    const metrics = {width, height, deviceScaleFactor, mobile};

    this.transportActions.setDeviceMetrics(metrics, callback);
  }

  command(metrics, callback) {
    this.metrics = metrics || {};

    return super.command(callback);
  }
}

module.exports = SetDeviceDimensions;