assert_equal "zh-TW", Locale.available.preferred(Locale.list("zh-Hant-TW", "de")).to_s
assert_equal "zh-TW", Locale.available.preferred(Locale.list("zh-TW", "de")).to_s
assert_equal "zh-HK", Locale.available.preferred(Locale.list("yue", "zh-HK", "de")).to_s
assert_equal "zh-TW", Locale.available.preferred(Locale.list("zh-Hant-TW", "de")).to_s
assert_equal "zh-TW", Locale.available.preferred(Locale.list("zh-TW", "de")).to_s
assert_equal "zh-HK", Locale.available.preferred(Locale.list("yue", "zh-HK", "de")).to_s