ionic-framework/angular/test/test-app/e2e/src/utils.ts

import { browser } from 'protractor';

export function goBack() {
  return browser.executeScript(`return window.history.back()`);
}

export function getProperty(selector: string, property: string) {
  return browser.executeScript(`
    return document.querySelector('${selector}')['${property}'];
  `);
}

export function getText(selector: string) {
  return browser.executeScript(`
    return document.querySelector('${selector}').textContent;
  `);
}

export function setProperty(selector: string, property: string, value: any) {
  const text = JSON.stringify(value);
  return browser.executeScript(`
    document.querySelector('${selector}')['${property}'] = ${text};
  `);
}

export function waitTime(time: number) {
  return new Promise(resolve => {
    setTimeout(resolve, time);
  });
}

export interface LifeCycleCount {
  ionViewWillEnter: number;
  ionViewDidEnter: number;
  ionViewWillLeave: number;
  ionViewDidLeave: number;
}

export function handleErrorMessages() {
  browser.manage().logs().get('browser').then(function(browserLog) {
    let severWarnings = false;

    for (let i; i <= browserLog.length - 1; i++) {
        if (browserLog[i].level.name === 'SEVERE') {
            console.log('\n' + browserLog[i].level.name);
            console.log('(Possibly exception) \n' + browserLog[i].message);

            severWarnings = true;
        }
    }

    expect(severWarnings).toBe(false);
  });
}

export async function testLifeCycle(selector: string, expected: LifeCycleCount) {
  await waitTime(50);
  expect(await getText(`${selector} #ngOnInit`)).toEqual('1');
  expect(await getText(`${selector} #ionViewWillEnter`)).toEqual(expected.ionViewWillEnter.toString());
  expect(await getText(`${selector} #ionViewDidEnter`)).toEqual(expected.ionViewDidEnter.toString());
  expect(await getText(`${selector} #ionViewWillLeave`)).toEqual(expected.ionViewWillLeave.toString());
  expect(await getText(`${selector} #ionViewDidLeave`)).toEqual(expected.ionViewDidLeave.toString());
}

export async function testStack(selector: string, expected: string[]) {
  const children = await browser.executeScript(`
    return Array.from(
      document.querySelector('${selector}').children
    ).map(el => el.tagName.toLowerCase());
  `);
  expect(children).toEqual(expected);
}