class WebTestCase extends PHPUnit_Extensions_Selenium2TestCase
{
    protected $captureScreenshotOnFailure = TRUE;
    protected $screenshotPath = '/../../screenshots';
    protected $screenshotUrl = 'http://localhost:8080/screenshots';

    protected function setUp() {
        $this->setBrowser('phantomjs');
        $this->setBrowserUrl("http://localhost:8080");
        $this->setHost('localhost');
    }
}

class Test extends WebTestCase
{

    public function testTitle()
    {
        $this->url('');
        assertEquals($this->title(), "My App");
    }
}

$ vendor/bin/phpunit
PHPUnit 4.6-ge85198b by Sebastian Bergmann and contributors.

Configuration read from /MyApp/phpunit.xml

F

Time: 231 ms, Memory: 5.50Mb

There was 1 failure:

1) Test::testTitle
Failed asserting that two strings are equal.
--- Expected
+++ Actual
@@ @@
-''
+'My App'

/MyApp/tests/functional/Test.php:7

FAILURES!
Tests: 1, Assertions: 1, Failures: 1.

<?php
class Test extends PHPUnit_Extensions_Selenium2TestCase
{

    protected function setUp() {
        $this->setBrowser('phantomjs');
        $this->setBrowserUrl("http://localhost:8080");
        $this->setHost('localhost');
    }

    public function testEnterText()
    {
        $this->url("/");

        try {

            $this->assertEquals($this->title(), "My App");

        } catch (Exception $e) {

            $this->screenshot( __DIR__.'/'.$this->getName().'-'.time(). '.png');
        }
    }

    public function screenshot($file)
    {
        $filedata = $this->currentScreenshot();
        file_put_contents($file, $filedata);
    }
}

<?php

class homepageTest extends PHPUnit_Extensions_Selenium2TestCase {

    private $listener;

    public function setUp() {

        // Your screenshots will be saved in '/var/www/vhosts/screenshots/'
        $screenshots_dir = '/var/www/vhosts/screenshots/';

        $this->listener = new PHPUnit_Extensions_Selenium2TestCase_ScreenshotListener($screenshots_dir);

        $this->setBrowser('firefox');
        $this->setBrowserUrl('https://netbeans.org');
    }

    public function tearDown() {
        $this->stop();
    }

    public function testNetbeansContainsHorses() {
        $this->url('https://netbeans.org');
        $this->assertContains('Equestrian', $this->title()); // Will fail on NetBeans page.
    }


    public function onNotSuccessfulTest($e) {
        $this->listener->addError($this, $e, null);
        parent::onNotSuccessfulTest($e);
    }
}

class MyBaseWebTests
{

    $this->directory = '/some_path_to_put_screenshots_in/';

    // Override PHPUnit_Extensions_Selenium2TestCase::onNotSuccessfulTest
    public function onNotSuccessfulTest(Exception $e)
    {
        $filedata   = $this->currentScreenshot();
        $file       = $this->directory . get_class($this) . '.png';
        file_put_contents($file, $filedata);

        parent::onNotSuccessfulTest($e);
    }
}

$fp = fopen('path/35.png', 'wb');
    fwrite($fp, $this->currentScreenshot());
    fclose($fp);
    sleep(1);