public function testCheckCommandExists()
 {
     $this->assertTrue($this->application->has('check'));
     $this->assertInstanceOf(Command::class, $this->application->get('check'));
 }
<?php

if (PHP_MAJOR_VERSION < 7) {
    fwrite(STDERR, "PHP7 is required\n");
    exit(1);
}
require __DIR__ . '/../vendor/autoload.php';
use ComposerRequireChecker\Cli\Application;
$application = new Application();
$application->run();