old_contents: import {assert} from '@webex/test-helper-chai';
  
  describe('plugin-devices', () => {
    beforeEach('initialize webex with the devices plugin', () => {});
  
    describe('#clear()', () => {});
    describe('#setLogoutTimer()', () => {});
    describe('#serialize()', () => {});
  
    it('temporary pass flag', () => assert.isTrue(true));
  });
  
new_contents: import {assert} from '@webex/test-helper-chai';
  import {cloneDeep} from 'lodash';
  import Devices from '@webex/internal-plugin-devices';
  import MockWebex from '@webex/test-helper-mock-webex';
  
  import dto from './wdm-dto';
  
  describe('plugin-devices', () => {
    let webex;
    let devices;
  
    beforeEach('initialize webex with the devices plugin', () => {
      webex = new MockWebex({
        children: {
          devices: Devices
        }
      });
  
      const deviceConfig = cloneDeep(dto);
  
      webex.internal.devices.set(deviceConfig);
  
      devices = webex.internal.devices;
    });
  
    describe('derived properties', () => {
      describe('#registered', () => {
        describe('when the device does not have a url', () => {
          beforeEach('remove the device\'s url', () => {
            devices.url = undefined;
          });
  
          it('should return false', () => {
            assert.isFalse(devices.registered);
          });
        });
  
        describe('when the device does have a url', () => {
          beforeEach('set the device\'s url', () => {
            devices.url = dto.url;
          });
  
          it('should return true', () => {
            assert.isTrue(devices.registered);
          });
        });
      });
    });
  
    describe('#clear()', () => {});
    describe('#setLogoutTimer()', () => {});
    describe('#serialize()', () => {});
  
    it('temporary pass flag', () => assert.isTrue(true));
  });
  
subject: add derived property tests