Sometimes the process no longer appears to be running when the signal is sent which causes a LogicException to be thrown. This doesn't appear to be consistent and I can reproduce it randomly on my local machine. To avoid having tests fail at random I decided that it's better to send the signal only if the process is still marked as running.

amne@wnbpowerbox:~/work/projects/symfony$ php7.4 src/Symfony/Component/Process/Tests/ErrorProcessInitiator.phpThe process"'php' '-r' 'echo '\''ready'\''; trigger_error('\''error'\'', E_USER_ERROR);'" exceeded the timeout of 0.5 seconds.amne@wnbpowerbox:~/work/projects/symfony$ php7.4 src/Symfony/Component/Process/Tests/ErrorProcessInitiator.phpThe process"'php' '-r' 'echo '\''ready'\''; trigger_error('\''error'\'', E_USER_ERROR);'" exceeded the timeout of 0.5 seconds.amne@wnbpowerbox:~/work/projects/symfony$ php7.4 src/Symfony/Component/Process/Tests/ErrorProcessInitiator.phpThe process"'php' '-r' 'echo '\''ready'\''; trigger_error('\''error'\'', E_USER_ERROR);'" exceeded the timeout of 0.5 seconds.amne@wnbpowerbox:~/work/projects/symfony$ php7.4 src/Symfony/Component/Process/Tests/ErrorProcessInitiator.phpThe process"'php' '-r' 'echo '\''ready'\''; trigger_error('\''error'\'', E_USER_ERROR);'" exceeded the timeout of 0.5 seconds.amne@wnbpowerbox:~/work/projects/symfony$ php7.4 src/Symfony/Component/Process/Tests/ErrorProcessInitiator.phpPHP Fatal error:  Uncaught Symfony\Component\Process\Exception\LogicException: Cannot send signal on a non running process.in /home/amne/work/projects/symfony/src/Symfony/Component/Process/Process.php:1502Stack trace:#0 /home/amne/work/projects/symfony/src/Symfony/Component/Process/Process.php(516): Symfony\Component\Process\Process->doSignal()#1 /home/amne/work/projects/symfony/src/Symfony/Component/Process/Tests/ErrorProcessInitiator.php(28): Symfony\Component\Process\Process->signal()#2 {main}  thrownin /home/amne/work/projects/symfony/src/Symfony/Component/Process/Process.php on line 1502

[Process] Fixed inconsistent test

00ee4ca

Sometimes the process no longer appears to be running when the signal is sent which causes a LogicException to be thrown.This doesn't appear to be consistent and I can reproduce it randomly on my local machine. To avoid having tests fail at randomI decided that it's better to send the signal only if the process is still marked as running.