I've recently been setting up PHPUnit for my PHP Framework Divergence and one change from PHPUnit 7 from the previous versions is that the TestListener no longer extends PHPUnit\Framework\BaseTestListener class (which has been removed entirely). Instead you can use the interface PHPUnit\Framework\TestListener.

Make sure you register the listener in your phpunit.xml file.

    <listeners>
        <listener class="Divergence\Tests\TestListener" file="./tests/Divergence/TestListener.php"></listener>
    </listeners>

Here's a simple example.

<?php
namespace Divergence\Tests;

use PHPUnit\Framework\TestCase;
use PHPUnit\Framework\TestListener as PHPUnit_TestListener;
use PHPUnit\Framework\Test;
use PHPUnit\Framework\TestSuite;

class TestListener implements  PHPUnit_TestListener
{
    public function __construct() {} // does nothing but throws an error if not here

    public function addError(Test $test, \Throwable $e, float $time): void
    {
        //printf("Error while running test '%s'.\n", $test->getName());
    }

    public function addWarning(Test $test, \PHPUnit\Framework\Warning $e, float $time): void
    {
        //printf("Warning while running test '%s'.\n", $test->getName());
    }
    

    public function addFailure(Test $test, \PHPUnit\Framework\AssertionFailedError $e, float $time): void
    {
        //printf("Test '%s' failed.\n", $test->getName());
    }

    public function addIncompleteTest(Test $test, \Throwable $e, float $time): void
    {
        //printf("Test '%s' is incomplete.\n", $test->getName());
    }

    public function addRiskyTest(Test $test, \Throwable $e, float $time): void
    {
        //printf("Test '%s' is deemed risky.\n", $test->getName());
    }

    public function addSkippedTest(Test $test, \Throwable $e, float $time): void
    {
        //printf("Test '%s' has been skipped.\n", $test->getName());
    }

    public function startTest(Test $test): void
    {
        //printf("Test '%s' started.\n", $test->getName());
    }

    public function endTest(Test $test, float $time): void
    {
        //printf("Test '%s' ended.\n", $test->getName());
    }

    public function startTestSuite(TestSuite $suite): void
    {
        if($suite->getName() == 'all') {
            printf("TestSuite '%s' started.\n", $suite->getName());
        }
    }

    public function endTestSuite(TestSuite $suite): void
    {
        if($suite->getName() == 'all') {
            printf("TestSuite '%s' ended.\n", $suite->getName());
        }
    }
}