diff --git a/src/parser.rs b/src/parser.rs
index 44f95b0f6..bf973659d 100644
--- a/src/parser.rs
+++ b/src/parser.rs
@@ -91,8 +91,8 @@ simple_enum_error! {
 }
 
 impl fmt::Display for ParseError {
-    fn fmt(&self, fmt: &mut Formatter) -> fmt::Result {
-        self.description().fmt(fmt)
+    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
+        fmt::Display::fmt(self.description(), f)
     }
 }
 
@@ -151,8 +151,8 @@ syntax_violation_enum! {
 }
 
 impl fmt::Display for SyntaxViolation {
-    fn fmt(&self, fmt: &mut Formatter) -> fmt::Result {
-        self.description().fmt(fmt)
+    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
+        fmt::Display::fmt(self.description(), f)
     }
 }
 
diff --git a/tests/unit.rs b/tests/unit.rs
index d5e81986a..9918ea316 100644
--- a/tests/unit.rs
+++ b/tests/unit.rs
@@ -512,6 +512,7 @@ fn test_syntax_violation_callback() {
     let v = violation.take().unwrap();
     assert_eq!(v, ExpectedDoubleSlash);
     assert_eq!(v.description(), "expected //");
+    assert_eq!(v.to_string(), "expected //");
 }
 
 #[test]