1 files changed, 13 insertions, 0 deletions
diff --git a/src/liballoc/str.rs b/src/liballoc/str.rs
index 870bf971cd3..f1bc9a83988 100644
--- a/src/liballoc/str.rs
+++ b/src/liballoc/str.rs
@@ -515,6 +515,10 @@ impl str {
 
     /// Create a [`String`] by repeating a string `n` times.
     ///
+    /// # Panics
+    ///
+    /// This function will panic if the capacity would overflow.
+    ///
     /// [`String`]: string/struct.String.html
     ///
     /// # Examples
@@ -524,6 +528,15 @@ impl str {
     /// ```
     /// assert_eq!("abc".repeat(4), String::from("abcabcabcabc"));
     /// ```
+    ///
+    /// A panic upon overflow:
+    ///
+    /// ```should_panic
+    /// fn main() {
+    ///     // this will panic at runtime
+    ///     "0123456789abcdef".repeat(usize::max_value());
+    /// }
+    /// ```
     #[stable(feature = "repeat_str", since = "1.16.0")]
     pub fn repeat(&self, n: usize) -> String {
         unsafe { String::from_utf8_unchecked(self.as_bytes().repeat(n)) }