bug #574 Fix console error listener when there is no command yet (ogizanagi)

This PR was merged into the master branch.

Discussion
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Fix console error listener when there is no command yet

Fixes an issue when there isn't any command yet and an error was triggered. For instance, when trying to use a non-existing command.

> PHP Fatal error:  Uncaught Symfony\Component\Debug\Exception\FatalThrowableError: Call to a member function getName() on null in src/AppBundle/EventListener/CheckRequirementsSubscriber.php:70

Commits
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81c459d Fix console error listener when there is no command yet

Author: javiereguiluz

src/AppBundle/EventListener/CheckRequirementsSubscriber.php

@@ -67,7 +67,7 @@ public function handleConsoleError(ConsoleErrorEvent $event)
     {
         $commandNames = ['doctrine:fixtures:load', 'doctrine:database:create', 'doctrine:schema:create', 'doctrine:database:drop'];
 
-        if (in_array($event->getCommand()->getName(), $commandNames, true)) {
+        if ($event->getCommand() && in_array($event->getCommand()->getName(), $commandNames, true)) {
             if ($this->isSQLitePlatform() && !extension_loaded('sqlite3')) {
                 $io = new SymfonyStyle($event->getInput(), $event->getOutput());
                 $io->error('This command requires to have the "sqlite3" PHP extension enabled because, by default, the Symfony Demo application uses SQLite to store its information.');