Rollup merge of #86140 - scottmcm:array-hash-facepalm, r=kennytm

[rust.git] / library / alloc / src / vec / mod.rs

diff --git a/library/alloc/src/vec/mod.rs b/library/alloc/src/vec/mod.rs
index 105c60e7bf0851c270b853db941db50806f43350..b59d2977add95ffb5fd45109940ac8a14eea1ff6 100644 (file)
--- a/library/alloc/src/vec/mod.rs
+++ b/library/alloc/src/vec/mod.rs
@@ -921,7 +921,7 @@ pub fn try_reserve_exact(&mut self, additional: usize) -> Result<(), TryReserveE
     ///
     /// ```
     /// let mut vec = Vec::with_capacity(10);
-    /// vec.extend([1, 2, 3].iter().cloned());
+    /// vec.extend([1, 2, 3]);
     /// assert_eq!(vec.capacity(), 10);
     /// vec.shrink_to_fit();
     /// assert!(vec.capacity() >= 3);
@@ -950,7 +950,7 @@ pub fn shrink_to_fit(&mut self) {
     /// ```
     /// #![feature(shrink_to)]
     /// let mut vec = Vec::with_capacity(10);
-    /// vec.extend([1, 2, 3].iter().cloned());
+    /// vec.extend([1, 2, 3]);
     /// assert_eq!(vec.capacity(), 10);
     /// vec.shrink_to(4);
     /// assert!(vec.capacity() >= 4);
@@ -984,7 +984,7 @@ pub fn shrink_to(&mut self, min_capacity: usize) {
     ///
     /// ```
     /// let mut vec = Vec::with_capacity(10);
-    /// vec.extend([1, 2, 3].iter().cloned());
+    /// vec.extend([1, 2, 3]);
     ///
     /// assert_eq!(vec.capacity(), 10);
     /// let slice = vec.into_boxed_slice();
@@ -2407,6 +2407,23 @@ fn clone_from(&mut self, other: &Self) {
     }
 }
 
+/// The hash of a vector is the same as that of the corresponding slice,
+/// as required by the `core::borrow::Borrow` implementation.
+///
+/// ```
+/// use std::hash::{BuildHasher, Hash, Hasher};
+///
+/// fn hash_of(x: impl Hash, b: &impl BuildHasher) -> u64 {
+///     let mut h = b.build_hasher();
+///     x.hash(&mut h);
+///     h.finish()
+/// }
+///
+/// let b = std::collections::hash_map::RandomState::new();
+/// let v: Vec<u8> = vec![0xa8, 0x3c, 0x09];
+/// let s: &[u8] = &[0xa8, 0x3c, 0x09];
+/// assert_eq!(hash_of(v, &b), hash_of(s, &b));
+/// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 impl<T: Hash, A: Allocator> Hash for Vec<T, A> {
     #[inline]
@@ -2586,7 +2603,7 @@ fn extend_desugared<I: Iterator<Item = T>>(&mut self, mut iterator: I) {
     /// ```
     /// let mut v = vec![1, 2, 3];
     /// let new = [7, 8];
-    /// let u: Vec<_> = v.splice(..2, new.iter().cloned()).collect();
+    /// let u: Vec<_> = v.splice(..2, new).collect();
     /// assert_eq!(v, &[7, 8, 3]);
     /// assert_eq!(u, &[1, 2]);
     /// ```