PhpCsFixer\ToolInfo::getComposerVersion PHP Method

    public static function getComposerVersion()
    {
        static $result;
        if (!self::isInstalledByComposer()) {
            throw new \LogicException('Cannot get composer version for tool not installed by composer.');
        }
        if (null === $result) {
            $composerInstalled = json_decode(file_get_contents(self::getScriptDir() . self::COMPOSER_INSTALLED_FILE), true);
            foreach ($composerInstalled as $package) {
                if (self::COMPOSER_PACKAGE_NAME === $package['name']) {
                    $result = $package['version'] . '#' . $package['dist']['reference'];
                    break;
                }
            }
        }
        return $result;
    }