From 14df54989aecb437e9cf6f3e066553cfbc979e26 Mon Sep 17 00:00:00 2001
From: Chris MacNaughton <chris.macnaughton@canonical.com>
Date: Thu, 22 Jun 2017 12:01:22 +0200
Subject: Ensure Guard types impl Display & Debug

Fixes #24372
---
 src/libstd/sync/mutex.rs  |  7 +++++++
 src/libstd/sync/rwlock.rs | 14 ++++++++++++++
 2 files changed, 21 insertions(+)

(limited to 'src/libstd/sync')

diff --git a/src/libstd/sync/mutex.rs b/src/libstd/sync/mutex.rs
index 9a242a96d46..fc6c7de9ef0 100644
--- a/src/libstd/sync/mutex.rs
+++ b/src/libstd/sync/mutex.rs
@@ -440,6 +440,13 @@ impl<'a, T: ?Sized + fmt::Debug> fmt::Debug for MutexGuard<'a, T> {
     }
 }
 
+#[stable(feature = "std_guard_impls", since = "1.20")]
+impl<'a, T: ?Sized + fmt::Display> fmt::Display for MutexGuard<'a, T> {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        (**self).fmt(f)
+    }
+}
+
 pub fn guard_lock<'a, T: ?Sized>(guard: &MutexGuard<'a, T>) -> &'a sys::Mutex {
     &guard.__lock.inner
 }
diff --git a/src/libstd/sync/rwlock.rs b/src/libstd/sync/rwlock.rs
index 95bc8d30932..944801e8a3b 100644
--- a/src/libstd/sync/rwlock.rs
+++ b/src/libstd/sync/rwlock.rs
@@ -370,6 +370,13 @@ impl<'a, T: fmt::Debug> fmt::Debug for RwLockReadGuard<'a, T> {
     }
 }
 
+#[stable(feature = "std_guard_impls", since = "1.20")]
+impl<'a, T: ?Sized + fmt::Display> fmt::Display for RwLockReadGuard<'a, T> {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        (**self).fmt(f)
+    }
+}
+
 #[stable(feature = "std_debug", since = "1.16.0")]
 impl<'a, T: fmt::Debug> fmt::Debug for RwLockWriteGuard<'a, T> {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
@@ -379,6 +386,13 @@ impl<'a, T: fmt::Debug> fmt::Debug for RwLockWriteGuard<'a, T> {
     }
 }
 
+#[stable(feature = "std_guard_impls", since = "1.20")]
+impl<'a, T: ?Sized + fmt::Display> fmt::Display for RwLockWriteGuard<'a, T> {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        (**self).fmt(f)
+    }
+}
+
 #[stable(feature = "rust1", since = "1.0.0")]
 impl<'rwlock, T: ?Sized> Deref for RwLockReadGuard<'rwlock, T> {
     type Target = T;
-- 
cgit 1.4.1-3-g733a5