@covers ::<!public> annotation broken

[cs278]

Q	A
PHPUnit version	9.4.0 (since 9.1.0)
PHP version	7.4.10
Installation Method	Both

Summary

Using the @covers ::<!public> annotation on an exception causes a PHP fatal error. Presumably other variations of this annotation are broken as well.

Current behavior

$ php -f phpunit-9.4.phar -- --coverage-filter myexceptiontest.php --coverage-text myexceptiontest.php  
PHPUnit 9.4.0 by Sebastian Bergmann and contributors.

PHP Fatal error:  Uncaught TypeError: Argument 2 passed to PHPUnit\SebastianBergmann\CodeUnit\CodeUnit::__construct() must be of the type string, bool given, called in phar:///tmp/chris.smith/tmp.YrkElvgwGm/phpunit-9.4.phar/sebastian-code-unit/CodeUnit.php on line 59 and defined in phar:///tmp/chris.smith/tmp.YrkElvgwGm/phpunit-9.4.phar/sebastian-code-unit/CodeUnit.php:126
Stack trace:
#0 phar:///tmp/chris.smith/tmp.YrkElvgwGm/phpunit-9.4.phar/sebastian-code-unit/CodeUnit.php(59): PHPUnit\SebastianBergmann\CodeUnit\CodeUnit->__construct()
#1 phar:///tmp/chris.smith/tmp.YrkElvgwGm/phpunit-9.4.phar/sebastian-code-unit/Mapper.php(180): PHPUnit\SebastianBergmann\CodeUnit\CodeUnit::forClassMethod()
#2 phar:///tmp/chris.smith/tmp.YrkElvgwGm/phpunit-9.4.phar/sebastian-code-unit/Mapper.php(160): PHPUnit\SebastianBergmann\CodeUnit\Mapper->methodsOfClass()
#3 phar:///tmp/chris.smith/tmp.YrkElvgwGm/phpunit-9.4.phar/sebastian-code-unit/Mapper.php(69): PHPUnit\SebastianBergmann\CodeUnit\Mapper->protectedAndPrivateMethodsOfClass()
#4 phar:/ in phar:///tmp/chris.smith/tmp.YrkElvgwGm/phpunit-9.4.phar/phpunit/TextUI/Command.php on line 100

How to reproduce

Trying to test the following code with coverage produces the error.

<?php

/**
 * @covers myexception::__construct
 * @covers myexception::<!public>
 */
final class myexceptiontest extends \PHPUnit\Framework\TestCase
{
    public function test()
    {
        $e = new myexception();
        self::assertSame('Hi', $e->getMessage());
    }
}

class myexception extends \exception
{
    public function __construct(\Throwable $previous = null)
    {
        parent::__construct('Hi', 0, $previous);
    }
}

Run PHPUnit with these arguments:

phpunit --coverage-filter myexceptiontest.php --coverage-text myexceptiontest.php  

It appears PHPUnit is trying to find the source file of the final private method \Exception::__clone, the correct behaviour I believe is to ignore parent methods.

Expected behavior

9.0 exhibits the expected behaviour.

$ php -f phpunit-9.0.phar -- --whitelist myexceptiontest.php --coverage-text myexceptiontest.php  
PHPUnit 9.0.2 by Sebastian Bergmann and contributors.

.                                                                   1 / 1 (100%)

Time: 185 ms, Memory: 14.00 MB

OK (1 test, 1 assertion)


Code Coverage Report:  
  2020-10-02 13:09:54  
                       
 Summary:              
  Classes: 50.00% (1/2)
  Methods: 50.00% (1/2)
  Lines:   40.00% (2/5)

myexception
  Methods: 100.00% ( 1/ 1)   Lines: 100.00% (  2/  2)

[sebastianbergmann]

Sorry, but I will not invest any time in attempting to debug or fix this. This functionality is deprecated and scheduled for removal. I will, of course, consider a pull request that fixes this.

[cs278]

I've submitted a PR to fix this, I've assumed you'll move this issue to that repository.