Symfony 2 -> Composer and CloudControl
Got same error after setting "minimum-stability":"dev" and running composer update.
for unknown reason symfony/symfony (dev-master ...) kept failing to download from source thus was being loaded from cache.
what worked for me was a mix of previous answers:
$ rm -rf vendor/symfony$ composer clearcache$ composer install
Sometimes I had to clean composer cache to remove strange errors, usually it's in
/home/user/.composer/cache You can also try to update composer with
php composer.phar self-updateI hope it runs for you.
I had the exact same error in my development directory.
What fixed it was :
$ rm -rf vendor/symfony$ php composer.phar installIt reinstalled symfony/symfony, symfony/icu, symfony/assetic-bundle, symfony/monolog-bundle and symfony/swiftmailer-bundle and now everything works !