src/Composer/Plugin/PluginManager.php
private function getInstallPath(PackageInterface $package, $global = false)
    {
        if (!$global) {
            return $this->composer->getInstallationManager()->getInstallPath($package);
        }

        return $this->globalComposer->getInstallationManager()->getInstallPath($package);
    }
private function getInstallPath(PackageInterface $package, $global = false)
    {
        if (!$global) {
            return $this->composer->getInstallationManager()->getInstallPath($package);
        }

        return $this->globalComposer->getInstallationManager()->getInstallPath($package);
    }
Retrieves the path a package is installed to.

@param PackageInterface $package
@param bool             $global  Whether this is a global package

@return string Install path