From 7b4cbbd12d88c8e64d9c7aa1e326c7c78f2a7ed9 Mon Sep 17 00:00:00 2001
From: Corey Farwell <coreyf@rwell.org>
Date: Sun, 28 Jan 2018 21:50:01 -0500
Subject: Document that `Index` ops can panic on `HashMap` & `BTreeMap`.

Fixes https://github.com/rust-lang/rust/issues/47011.
---
 src/liballoc/btree/map.rs | 5 +++++
 1 file changed, 5 insertions(+)

(limited to 'src/liballoc/btree')

diff --git a/src/liballoc/btree/map.rs b/src/liballoc/btree/map.rs
index b114dc640fb..b320bed5432 100644
--- a/src/liballoc/btree/map.rs
+++ b/src/liballoc/btree/map.rs
@@ -1748,6 +1748,11 @@ impl<'a, K: Ord, Q: ?Sized, V> Index<&'a Q> for BTreeMap<K, V>
 {
     type Output = V;
 
+    /// Returns a reference to the value corresponding to the supplied key.
+    ///
+    /// # Panics
+    ///
+    /// Panics if the key is not present in the `BTreeMap`.
     #[inline]
     fn index(&self, key: &Q) -> &V {
         self.get(key).expect("no entry found for key")
-- 
cgit 1.4.1-3-g733a5