public function addBrowserFile(string $filename) : void
    {
        $decodedFileContent = $this->loadFile($filename);

        Assertion::isArray($decodedFileContent, 'required "browsers" structure has to be an array');

        $browserFactory = new BrowserFactory();

        foreach (array_keys($decodedFileContent) as $browserName) {
            $browserData = $decodedFileContent[$browserName];
            $browserName = (string) $browserName;

            $this->collection->addBrowser($browserName, $browserFactory->build($browserData, $browserName));
        }
    }