Confusing warning message "Class ... cannot be found " when class does not extend TestCase

[ciaranmcnulty]

Q	A
PHPUnit version	10.1.3
PHP version	8.2.3
Installation Method	Composer

Current behavior

When a *Test.php class exists but does not extend TestCase, the warning emitted is:

Class $classname cannot be found in $path

This is confusing because there is a valid class at that path, so the user spends time checking namespace match, autoloader configuration etc.

How to reproduce

Create a class /tests/Foo.php:

<?php

namespace Foo;

class FooTest
{
}

Warning when running PHPUnit:

There was 1 PHPUnit test runner warning:

1) Class FooTest cannot be found in /Users/ciaranmcnulty/Code/phpunit-repro/tests/FooTest.php

Expected behavior

The text can be improved something like:

1) Class FooTest at /Users/ciaranmcnulty/Code/phpunit-repro/tests/FooTest.php is not a TestCase

[ciaranmcnulty]

I guess this case would need to throw a different (new) exception