Using Explicit Checks

With recheck, you have multiple options of how to use it. You can use a RecheckDriver, which would make recheck completely transparent to use. For a more obvious and spelled-out usage as pure checking library, you can call the check methods explicitly.

A very basic test with Selenium and explicit calls to check could look like this:

package com.mycompany;

import org.junit.*;
import org.openqa.selenium.*;
import org.openqa.selenium.chrome.*;
import de.retest.recheck.*;
import de.retest.recheck.persistence.*;

public class MyFirstTest {

  private WebDriver driver;
  private Recheck re;

  @Before
  public void setUp() {
    re = new RecheckImpl();
    System.setProperty("webdriver.chrome.driver", "C:\\pathto\\chromedriver.exe");
    ChromeOptions options = new ChromeOptions();
    options.addArguments("--headless", "--window-size=1280,720");
    driver = new ChromeDriver(options);
  }

  @Test
  public void google() throws Exception {
    re.startTest();

    driver.get("http://google.com");
    re.check(driver, "open");

    re.capTest();
  }

  @After
  public void tearDown() {
    driver.quit();
    re.cap();
  }
}

The @Before annotated method creates both the Recheck instance to use, as well as the ChromeDriver. The @Test annotated method first tells recheck to start the test (calling startTest), then load the Google start page into Chrome. Then it will recheck the current version of the page against a previous, expected version (called Golden Master) by invoking check and giving it a semantic and unique identifier.

Tip

If you only want to test specific GUI elements, you can also pass a single WebElement to the check method instead of the WebDriver to test the entire page.

During a typical, more elaborate test, you would call check multiple times, each time with a unique identifier. Since differences are not that uncommon, we do not want our test to fail immediately. So the calls to the check method will gather all differences, but not immediately make the test fail. To make the test fail in case of differences, the capTest method is called at the end of the test. Should you forget to do so, then a message in the log will tell you. After the test finishes, the @After method shuts down Chrome by calling quit on the driver and makes recheck create a summary report file of all encountered changes by calling cap.

When you set up Maven correctly, then you can now execute that test case locally.