From bde855518b9f21fe877e1ed62eaa114861131d15 Mon Sep 17 00:00:00 2001
From: Mazdak Farrokhzad <twingoow@gmail.com>
Date: Tue, 20 Feb 2018 05:52:26 +0100
Subject: [PATCH 1/2] RefCell: document panics in Clone, PartialEq, PartialOrd,
 Ord. Fixes #47400

---
 src/libcore/cell.rs | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/src/libcore/cell.rs b/src/libcore/cell.rs
index ec0d1b704dceb..e91b2c793c5e5 100644
--- a/src/libcore/cell.rs
+++ b/src/libcore/cell.rs
@@ -863,6 +863,9 @@ impl<T: ?Sized> !Sync for RefCell<T> {}
 
 #[stable(feature = "rust1", since = "1.0.0")]
 impl<T: Clone> Clone for RefCell<T> {
+    /// # Panics
+    ///
+    /// Panics if the value is currently mutably borrowed.
     #[inline]
     fn clone(&self) -> RefCell<T> {
         RefCell::new(self.borrow().clone())
@@ -880,6 +883,9 @@ impl<T:Default> Default for RefCell<T> {
 
 #[stable(feature = "rust1", since = "1.0.0")]
 impl<T: ?Sized + PartialEq> PartialEq for RefCell<T> {
+    /// # Panics
+    ///
+    /// Panics if the value is currently mutably borrowed.
     #[inline]
     fn eq(&self, other: &RefCell<T>) -> bool {
         *self.borrow() == *other.borrow()
@@ -891,26 +897,41 @@ impl<T: ?Sized + Eq> Eq for RefCell<T> {}
 
 #[stable(feature = "cell_ord", since = "1.10.0")]
 impl<T: ?Sized + PartialOrd> PartialOrd for RefCell<T> {
+    /// # Panics
+    ///
+    /// Panics if the value is currently mutably borrowed.
     #[inline]
     fn partial_cmp(&self, other: &RefCell<T>) -> Option<Ordering> {
         self.borrow().partial_cmp(&*other.borrow())
     }
 
+    /// # Panics
+    ///
+    /// Panics if the value is currently mutably borrowed.
     #[inline]
     fn lt(&self, other: &RefCell<T>) -> bool {
         *self.borrow() < *other.borrow()
     }
 
+    /// # Panics
+    ///
+    /// Panics if the value is currently mutably borrowed.
     #[inline]
     fn le(&self, other: &RefCell<T>) -> bool {
         *self.borrow() <= *other.borrow()
     }
 
+    /// # Panics
+    ///
+    /// Panics if the value is currently mutably borrowed.
     #[inline]
     fn gt(&self, other: &RefCell<T>) -> bool {
         *self.borrow() > *other.borrow()
     }
 
+    /// # Panics
+    ///
+    /// Panics if the value is currently mutably borrowed.
     #[inline]
     fn ge(&self, other: &RefCell<T>) -> bool {
         *self.borrow() >= *other.borrow()
@@ -919,6 +940,9 @@ impl<T: ?Sized + PartialOrd> PartialOrd for RefCell<T> {
 
 #[stable(feature = "cell_ord", since = "1.10.0")]
 impl<T: ?Sized + Ord> Ord for RefCell<T> {
+    /// # Panics
+    ///
+    /// Panics if the value is currently mutably borrowed.
     #[inline]
     fn cmp(&self, other: &RefCell<T>) -> Ordering {
         self.borrow().cmp(&*other.borrow())

From f8ebb3f09fa98cf5583f6bd8d5677a1f4dd0941d Mon Sep 17 00:00:00 2001
From: Mazdak Farrokhzad <twingoow@gmail.com>
Date: Tue, 27 Feb 2018 15:48:50 +0100
Subject: [PATCH 2/2] fix wording on panics in binary operators on RefCells"

---
 src/libcore/cell.rs | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/src/libcore/cell.rs b/src/libcore/cell.rs
index e91b2c793c5e5..419ae96b94bd6 100644
--- a/src/libcore/cell.rs
+++ b/src/libcore/cell.rs
@@ -885,7 +885,7 @@ impl<T:Default> Default for RefCell<T> {
 impl<T: ?Sized + PartialEq> PartialEq for RefCell<T> {
     /// # Panics
     ///
-    /// Panics if the value is currently mutably borrowed.
+    /// Panics if the value in either `RefCell` is currently borrowed.
     #[inline]
     fn eq(&self, other: &RefCell<T>) -> bool {
         *self.borrow() == *other.borrow()
@@ -899,7 +899,7 @@ impl<T: ?Sized + Eq> Eq for RefCell<T> {}
 impl<T: ?Sized + PartialOrd> PartialOrd for RefCell<T> {
     /// # Panics
     ///
-    /// Panics if the value is currently mutably borrowed.
+    /// Panics if the value in either `RefCell` is currently borrowed.
     #[inline]
     fn partial_cmp(&self, other: &RefCell<T>) -> Option<Ordering> {
         self.borrow().partial_cmp(&*other.borrow())
@@ -907,7 +907,7 @@ impl<T: ?Sized + PartialOrd> PartialOrd for RefCell<T> {
 
     /// # Panics
     ///
-    /// Panics if the value is currently mutably borrowed.
+    /// Panics if the value in either `RefCell` is currently borrowed.
     #[inline]
     fn lt(&self, other: &RefCell<T>) -> bool {
         *self.borrow() < *other.borrow()
@@ -915,7 +915,7 @@ impl<T: ?Sized + PartialOrd> PartialOrd for RefCell<T> {
 
     /// # Panics
     ///
-    /// Panics if the value is currently mutably borrowed.
+    /// Panics if the value in either `RefCell` is currently borrowed.
     #[inline]
     fn le(&self, other: &RefCell<T>) -> bool {
         *self.borrow() <= *other.borrow()
@@ -923,7 +923,7 @@ impl<T: ?Sized + PartialOrd> PartialOrd for RefCell<T> {
 
     /// # Panics
     ///
-    /// Panics if the value is currently mutably borrowed.
+    /// Panics if the value in either `RefCell` is currently borrowed.
     #[inline]
     fn gt(&self, other: &RefCell<T>) -> bool {
         *self.borrow() > *other.borrow()
@@ -931,7 +931,7 @@ impl<T: ?Sized + PartialOrd> PartialOrd for RefCell<T> {
 
     /// # Panics
     ///
-    /// Panics if the value is currently mutably borrowed.
+    /// Panics if the value in either `RefCell` is currently borrowed.
     #[inline]
     fn ge(&self, other: &RefCell<T>) -> bool {
         *self.borrow() >= *other.borrow()
@@ -942,7 +942,7 @@ impl<T: ?Sized + PartialOrd> PartialOrd for RefCell<T> {
 impl<T: ?Sized + Ord> Ord for RefCell<T> {
     /// # Panics
     ///
-    /// Panics if the value is currently mutably borrowed.
+    /// Panics if the value in either `RefCell` is currently borrowed.
     #[inline]
     fn cmp(&self, other: &RefCell<T>) -> Ordering {
         self.borrow().cmp(&*other.borrow())