@preserveGlobalState

@preserveGlobalState

When a test is run in a separate process, PHPUnit will attempt to preserve the global state from the parent process by serializing all globals in the parent process and unserializing them in the child process. This can cause problems if the parent process contains globals that are not serializable. To fix this, you can prevent PHPUnit from preserving global state with the @preserveGlobalState annotation.

use PHPUnit\Framework\TestCase;

class MyTest extends TestCase
{
    /**
     * @runInSeparateProcess
     * @preserveGlobalState disabled
     */
    public function testInSeparateProcess()
    {
        // ...
    }
}