Application.php

<?php

namespace FBeans\Blatask\IRC;

use FBeans\BlaIRC\Command;
use FBeans\BlaIRC\Application As BlaApplication;
use Symfony\Component\Console\Input\InputInterface;
use Symfony\Component\Console\Output\OutputInterface;
use Symfony\Component\Process\Process;

class Application extends BlaApplication
{
    public function commands(): Array
    {
        $command = new Command;
        $command->setName('task:list');

        // argument 0 is the command name
        $command->addArgument(1);

        $command->setExecuteCallback(
            function (InputInterface $input, OutputInterface $output) {
                $filter = $input->getArgument(1);

                $process_argument = ["task", "list"];

                if ($filter) {
                    $process_argument[] = $filter;
                }

                $process = new Process($process_argument);

                $process->run();

                if (!$process->isSuccessful()) {
                    $output->write($process->getErrorOutput());
                    return Command::SUCCESS;
                }
                $array_output = explode("\n", $process->getOutput());
                $output->writeLn($array_output[count($array_output) - 2]);
                return Command::FAILURE;
            }
        );

        return [$command];
    }
}