Updates the value of ICU_DATA_VERSION to '4.2' if needed

composer.json

...
"scripts": {
        "post-install-cmd": [
            "Mopa\\Bundle\\BootstrapBundle\\Composer\\ScriptHandler::postInstallSymlinkTwitterBootstrap",
            "vendor/bin/security-checker security:check",
            "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::buildBootstrap",
            "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::clearCache",
            "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::installAssets",
            "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::installRequirementsFile",
            "YourBundle\\Composer\\ScriptHandler::updateIcuVersion"
        ],
        "post-update-cmd": [
            "Mopa\\Bundle\\BootstrapBundle\\Composer\\ScriptHandler::postInstallSymlinkTwitterBootstrap",
            "vendor/bin/security-checker security:check",
            "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::buildBootstrap",
            "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::clearCache",
            "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::installAssets",
            "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::installRequirementsFile",
            "YourBundle\\Composer\\ScriptHandler::updateIcuVersion"
        ]
    },
...

ScriptHandler.php

<?php

namespace YourBundle\Composer;

class ScriptHandler
{
    public static function updateIcuVersion($event)
    {
        if (false === self::isCentos()) {
            return;
        }
        $options = self::getOptions($event);
        $vendorDir = $options['symfony-vendor-dir'];

        if (!is_dir($vendorDir)) {
            echo 'The symfony-vendor-dir ('.$vendorDir.') specified in composer.json was not found in '.getcwd().', can not build bootstrap file.'.PHP_EOL;

            return;
        }
        $LocaleClassFile = $vendorDir.'/symfony/symfony/src/Symfony/Component/Locale/Locale.php';
        if (!file_exists($LocaleClassFile)) {
            echo 'The Locale class file ('.$LocaleClassFile.') was not found.'.PHP_EOL;

            return;
        }
        $LocaleClass = file_get_contents($LocaleClassFile);
        if (false === strpos($LocaleClass, "const ICU_DATA_VERSION = '49';")) {
            echo 'String "const ICU_DATA_VERSION = \'49\';" not found in '.$LocaleClassFile.', the script might need an update'.PHP_EOL;

            return;
        }
        $LocaleClass = str_replace("const ICU_DATA_VERSION = '49';", "const ICU_DATA_VERSION = '4.2';", $LocaleClass);
        file_put_contents($LocaleClassFile, $LocaleClass);
    }

    protected static function getOptions($event)
    {
        $options = array_merge(array(
            'symfony-vendor-dir' => 'vendor',
        ), $event->getComposer()->getPackage()->getExtra());

        return $options;
    }

    protected static function isCentos()
    {
        $ret = exec('cat /etc/*-release', $release);
        foreach ($release as $v) {
            if (false !== stripos($v, 'centos')) {
                return true;
            }
        }

        return false;
    }
}