add Debug trait for Lsn

Author: jeff-davis

tokio-postgres/src/types.rs

@@ -5,8 +5,10 @@
 #[doc(inline)]
 pub use postgres_types::*;
 
+use std::fmt;
+
 /// Log Sequence Number for PostgreSQL Write-Ahead Log (transaction log).
-#[derive(Clone, Copy, Debug, Eq, Ord, PartialEq, PartialOrd)]
+#[derive(Clone, Copy, Eq, Ord, PartialEq, PartialOrd)]
 pub struct Lsn(u64);
 
 impl From<&str> for Lsn {
@@ -38,3 +40,11 @@ impl From<Lsn> for String {
         format!("{:X}/{:X}", lsn.0 >> 32, lsn.0 & 0x00000000ffffffff)
     }
 }
+
+impl fmt::Debug for Lsn {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_tuple("Lsn")
+         .field(&String::from(*self))
+         .finish()
+    }
+}