AssetManager\Resolver\AliasPathStackResolver::addAlias PHP Method

    private function addAlias($alias, $path)
    {
        if (!is_string($path)) {
            throw new Exception\InvalidArgumentException(sprintf('Invalid path provided; must be a string, received %s', gettype($path)));
        }
        if (!is_string($alias)) {
            throw new Exception\InvalidArgumentException(sprintf('Invalid alias provided; must be a string, received %s', gettype($alias)));
        }
        $this->aliases[$alias] = $this->normalizePath($path);
    }