extern void check_xml (std::string ref, std::string test, std::list<std::string> ignore, bool ignore_whitespace = false);
extern void check_file (boost::filesystem::path ref, boost::filesystem::path check);
extern std::shared_ptr<dcp::MonoPictureAsset> simple_picture (boost::filesystem::path path, std::string suffix);
-extern std::shared_ptr<dcp::SoundAsset> simple_sound (boost::filesystem::path path, std::string suffix, dcp::MXFMetadata mxf_meta);
+extern std::shared_ptr<dcp::SoundAsset> simple_sound (boost::filesystem::path path, std::string suffix, dcp::MXFMetadata mxf_meta, std::string language);
extern std::shared_ptr<dcp::DCP> make_simple (boost::filesystem::path path, int reels = 1);
extern std::shared_ptr<dcp::DCP> make_simple_with_interop_subs (boost::filesystem::path path);
extern std::shared_ptr<dcp::DCP> make_simple_with_smpte_subs (boost::filesystem::path path);