Implement Display and Hash for std::num::Wrapping

Also, change the `Debug` implementation to only show the inner value.

Fixes #33006.

src/libcore/num/mod.rs

@@ -38,9 +38,23 @@ use slice::SliceExt;
 /// all standard arithmetic operations on the underlying value are
 /// intended to have wrapping semantics.
 #[stable(feature = "rust1", since = "1.0.0")]
-#[derive(PartialEq, Eq, PartialOrd, Ord, Clone, Copy, Debug, Default)]
+#[derive(PartialEq, Eq, PartialOrd, Ord, Clone, Copy, Default, Hash)]
 pub struct Wrapping<T>(#[stable(feature = "rust1", since = "1.0.0")] pub T);
 
+#[stable(feature = "rust1", since = "1.0.0")]
+impl<T: fmt::Debug> fmt::Debug for Wrapping<T> {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        self.0.fmt(f)
+    }
+}
+
+#[stable(feature = "wrapping_display", since = "1.10.0")]
+impl<T: fmt::Display> fmt::Display for Wrapping<T> {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        self.0.fmt(f)
+    }
+}
+
 mod wrapping;
 
 // All these modules are technically private and only exposed for libcoretest: