`expectProcessExit()`

[sebastianbergmann]

When we have this code ...

ProcessExit.php

<?php declare(strict_types=1);
final class ProcessExit
{
    public function doSomething(): never
    {
        exit(1);
    }
}

ProcessExitTest.php

<?php declare(strict_types=1);
use PHPUnit\Framework\Attributes\CoversClass;
use PHPUnit\Framework\Attributes\RunInSeparateProcess;
use PHPUnit\Framework\TestCase;

#[CoversClass(ProcessExit::class)]
final class ProcessExitTest extends TestCase
{
    #[RunInSeparateProcess]
    public function testOne(): void
    {
        (new ProcessExit)->doSomething();
    }
}

and run PHPUnit then we currently get

PHPUnit 12.2.1 by Sebastian Bergmann and contributors.

Runtime:       PHP 8.4.8
Configuration: /tmp/example/phpunit.xml

E                                                                   1 / 1 (100%)

Time: 00:00.156, Memory: 25.68 MB

There was 1 error:

1) ProcessExitTest::testOne
Test was run in child process and ended unexpectedly

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

Due to #[RunInSeparateProcess], the test method is run in a separate process and the exit statement does not terminate the PHP process in which PHPUnit's test runner is running.

The child process that is used to run the test ends unexpectedly and this is interpreted by PHPUnit as an error.

There are situations, though, when the child process using exit is expected. However, this cannot be expected currently.

The following should be made possible:

<?php declare(strict_types=1);
use PHPUnit\Framework\Attributes\CoversClass;
use PHPUnit\Framework\Attributes\RunInSeparateProcess;
use PHPUnit\Framework\TestCase;

#[CoversClass(ProcessExit::class)]
final class ProcessExitTest extends TestCase
{
    #[RunInSeparateProcess]
    public function testOne(): void
    {
        $this->expectProcessExit(1);

        (new ProcessExit)->doSomething();
    }
}