public function isPackageInstalled(PackageInterface $package)
    {
        return $this->filesystem->exists($this->config->getInstallDir() . '/' . $package->getName() . '/.bower.json');
    }
public function isPackageInstalled(PackageInterface $package)
    {
        return $this->filesystem->exists($this->config->getInstallDir() . '/' . $package->getName() . '/.bower.json');
    }
public function isPackageInstalled ( PackageInterface $ package ) { return $ this -> filesystem -> exists ( $ this -> config -> getInstallDir ( ) . '/' . $ package -> getName ( ) . '/.bower.json' ) ; }
Check if package is installed

@param  PackageInterface $package
@return bool
Check if package is installed