1 files changed, 11 insertions, 0 deletions
diff --git a/src/diagnostic.rs b/src/diagnostic.rs
index 1bf9f42f..2548e1d5 100644
--- a/src/diagnostic.rs
+++ b/src/diagnostic.rs
@@ -4,6 +4,8 @@
 //! layout on a best effort process, generating diagnostics for incorrect
 //! things.
 
+use std::fmt::{self, Display, Formatter};
+
 /// A diagnostic that arose in parsing or layouting.
 #[derive(Debug, Clone, Eq, PartialEq, Ord, PartialOrd)]
 #[cfg_attr(feature = "serialize", derive(serde::Serialize))]
@@ -30,6 +32,15 @@ impl Diagnostic {
     }
 }
 
+impl Display for Level {
+    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
+        f.pad(match self {
+            Self::Warning => "warning",
+            Self::Error => "error",
+        })
+    }
+}
+
 /// Construct a diagnostic with `Error` level.
 ///
 /// ```