diff --git a/src/config.rs b/src/config.rs
index a740475c..7f56e797 100644
--- a/src/config.rs
+++ b/src/config.rs
@@ -1248,117 +1248,6 @@ mod tests {
         assert_eq!(cfg.realized_text_direction(), TextDirection::RightToLeft);
     }
 
-    #[test]
-    fn text_drection_from_lang_code() {
-        // test all right-to-left languages
-        assert_eq!(
-            TextDirection::from_lang_code("ar"),
-            TextDirection::RightToLeft
-        );
-        assert_eq!(
-            TextDirection::from_lang_code("ara"),
-            TextDirection::RightToLeft
-        );
-        assert_eq!(
-            TextDirection::from_lang_code("arc"),
-            TextDirection::RightToLeft
-        );
-        assert_eq!(
-            TextDirection::from_lang_code("ae"),
-            TextDirection::RightToLeft
-        );
-        assert_eq!(
-            TextDirection::from_lang_code("ave"),
-            TextDirection::RightToLeft
-        );
-        assert_eq!(
-            TextDirection::from_lang_code("egy"),
-            TextDirection::RightToLeft
-        );
-        assert_eq!(
-            TextDirection::from_lang_code("he"),
-            TextDirection::RightToLeft
-        );
-        assert_eq!(
-            TextDirection::from_lang_code("heb"),
-            TextDirection::RightToLeft
-        );
-        assert_eq!(
-            TextDirection::from_lang_code("nqo"),
-            TextDirection::RightToLeft
-        );
-        assert_eq!(
-            TextDirection::from_lang_code("pal"),
-            TextDirection::RightToLeft
-        );
-        assert_eq!(
-            TextDirection::from_lang_code("phn"),
-            TextDirection::RightToLeft
-        );
-        assert_eq!(
-            TextDirection::from_lang_code("sam"),
-            TextDirection::RightToLeft
-        );
-        assert_eq!(
-            TextDirection::from_lang_code("syc"),
-            TextDirection::RightToLeft
-        );
-        assert_eq!(
-            TextDirection::from_lang_code("syr"),
-            TextDirection::RightToLeft
-        );
-        assert_eq!(
-            TextDirection::from_lang_code("fa"),
-            TextDirection::RightToLeft
-        );
-        assert_eq!(
-            TextDirection::from_lang_code("per"),
-            TextDirection::RightToLeft
-        );
-        assert_eq!(
-            TextDirection::from_lang_code("fas"),
-            TextDirection::RightToLeft
-        );
-        assert_eq!(
-            TextDirection::from_lang_code("ku"),
-            TextDirection::RightToLeft
-        );
-        assert_eq!(
-            TextDirection::from_lang_code("kur"),
-            TextDirection::RightToLeft
-        );
-        assert_eq!(
-            TextDirection::from_lang_code("ur"),
-            TextDirection::RightToLeft
-        );
-        assert_eq!(
-            TextDirection::from_lang_code("urd"),
-            TextDirection::RightToLeft
-        );
-
-        // test some left-to-right languages
-        assert_eq!(
-            TextDirection::from_lang_code("de"),
-            TextDirection::LeftToRight
-        );
-        assert_eq!(
-            TextDirection::from_lang_code("en"),
-            TextDirection::LeftToRight
-        );
-        assert_eq!(
-            TextDirection::from_lang_code("es"),
-            TextDirection::LeftToRight
-        );
-        assert_eq!(
-            TextDirection::from_lang_code("ja"),
-            TextDirection::LeftToRight
-        );
-        assert_eq!(
-            TextDirection::from_lang_code("sv"),
-            TextDirection::LeftToRight
-        );
-    }
-
     #[test]
     #[should_panic(expected = "Invalid configuration file")]
     fn invalid_language_type_error() {