diff --git a/lang/tests/tokens.rs b/lang/tests/tokens.rs
index 6a6310f..1cf89a8 100644
--- a/lang/tests/tokens.rs
+++ b/lang/tests/tokens.rs
@@ -138,8 +138,28 @@ fn main() {
             Lexeme(30, "number12345"),
             Lexeme(30, "____"),
             Lexeme(30, "_"),
+            Lexeme(17, ""), Lexeme(30, "leading-minus"),
+            Lexeme(30, "trailing-minus-"),
         ]);
 
+        eprint!("Initializing tokeniser.. ");
+        tokeniser_init(c"tests/tokens/function.l".as_ptr());
+        eprintln!("ok.");
+
+        assert_eq!(&collect_tokens()[..], &[
+            Lexeme(4, ""),
+            Lexeme(30, "my-function"),
+            Lexeme(19, ""),
+            Lexeme(18, ""),
+            Lexeme(12, ""),
+            Lexeme(11, ""),
+            Lexeme(21, ""),
+            Lexeme(5, ""),
+            Lexeme(10, ""),
+            Lexeme(23, ""),
+            Lexeme(20, ""),
+            ]);
+
         eprintln!("Finished tokenising.");
     }
 }
diff --git a/lang/tests/tokens/identifier.l b/lang/tests/tokens/identifier.l
index 59e27a2..9682057 100644
--- a/lang/tests/tokens/identifier.l
+++ b/lang/tests/tokens/identifier.l
@@ -5,3 +5,5 @@ mixedCASEIdent
 number12345
 ____
 _
+-leading-minus
+trailing-minus-