Process Isolation does not work with phpunit.phar

[olemartinorg]

Q	A
PHPUnit version	8.0.0
PHP version	Both 7.3.1 and 7.2.14
Installation Method	PHAR

Steps to reproduce:

1. Install PHPUnit 8.0.0 via phar:
   wget https://phar.phpunit.de/phpunit-8.0.0.phar && chmod a+x phpunit-8.0.0.phar

2. With any test file:

<?php
class Test extends PHPUnit\Framework\TestCase {
    public function testTrue(): void {
        $this->assertTrue(true);
    }
}

3. Run it with process isolation:
   ./phpunit-8.0.0.phar --process-isolation test.php

Observe the failure:

PHPUnit 8.0.0 by Sebastian Bergmann and contributors.

E                                                                   1 / 1 (100%)

Time: 124 ms, Memory: 10.00MB

There was 1 error:

1) Test::testTrue
PHPUnit\Framework\Exception: PHP Fatal error:  strict_types declaration must be the very first statement in the script in /path/phpunit-8.0.0.phar on line 2
PHP Stack trace:
PHP   1. {main}() Standard input code:0

Fatal error: strict_types declaration must be the very first statement in the script in /path/phpunit-8.0.0.phar on line 2

Call Stack:
    0.0008     511120   1. {main}() Standard input code:0

ERRORS!
Tests: 1, Assertions: 0, Errors: 1.

[sebastianbergmann]

It seems that there is a bug in PHP that when a PHAR is include()d or require()d and the PHAR's bootstrap script has a shebang such as #!/usr/bin/env php on its first line followed by <?php declare(strict_types=1); on its second line then PHP wrongly triggers a

strict_types declaration must be the very first statement in the script

compiler error.

[sebastianbergmann]

The PHP bug is tracked in https://bugs.php.net/bug.php?id=77561.