Auto merge of #86879 - YohDeadfall:stabilize-vec-shrink-to, r=dtolnay

Stabilize Vec<T>::shrink_to

This PR stabilizes `shrink_to` feature and closes the corresponding issue. The second point was addressed already, and no `panic!` should occur.

Closes #56431.

Author: bors

library/alloc/src/collections/binary_heap.rs

@@ -973,7 +973,6 @@ impl<T> BinaryHeap<T> {
     /// # Examples
     ///
     /// ```
-    /// #![feature(shrink_to)]
     /// use std::collections::BinaryHeap;
     /// let mut heap: BinaryHeap<i32> = BinaryHeap::with_capacity(100);
     ///
@@ -982,7 +981,7 @@ impl<T> BinaryHeap<T> {
     /// assert!(heap.capacity() >= 10);
     /// ```
     #[inline]
-    #[unstable(feature = "shrink_to", reason = "new API", issue = "56431")]
+    #[stable(feature = "shrink_to", since = "1.56.0")]
     pub fn shrink_to(&mut self, min_capacity: usize) {
         self.data.shrink_to(min_capacity)
     }

library/alloc/src/collections/vec_deque/mod.rs

@@ -816,7 +816,6 @@ impl<T, A: Allocator> VecDeque<T, A> {
     /// # Examples
     ///
     /// ```
-    /// #![feature(shrink_to)]
     /// use std::collections::VecDeque;
     ///
     /// let mut buf = VecDeque::with_capacity(15);
@@ -827,7 +826,7 @@ impl<T, A: Allocator> VecDeque<T, A> {
     /// buf.shrink_to(0);
     /// assert!(buf.capacity() >= 4);
     /// ```
-    #[unstable(feature = "shrink_to", reason = "new API", issue = "56431")]
+    #[stable(feature = "shrink_to", since = "1.56.0")]
     pub fn shrink_to(&mut self, min_capacity: usize) {
         let min_capacity = cmp::min(min_capacity, self.capacity());
         // We don't have to worry about an overflow as neither `self.len()` nor `self.capacity()`

library/alloc/src/string.rs

@@ -1100,7 +1100,6 @@ impl String {
     /// # Examples
     ///
     /// ```
-    /// #![feature(shrink_to)]
     /// let mut s = String::from("foo");
     ///
     /// s.reserve(100);
@@ -1113,7 +1112,7 @@ impl String {
     /// ```
     #[cfg(not(no_global_oom_handling))]
     #[inline]
-    #[unstable(feature = "shrink_to", reason = "new API", issue = "56431")]
+    #[stable(feature = "shrink_to", since = "1.56.0")]
     pub fn shrink_to(&mut self, min_capacity: usize) {
         self.vec.shrink_to(min_capacity)
     }

library/alloc/src/vec/mod.rs

@@ -947,7 +947,6 @@ impl<T, A: Allocator> Vec<T, A> {
     /// # Examples
     ///
     /// ```
-    /// #![feature(shrink_to)]
     /// let mut vec = Vec::with_capacity(10);
     /// vec.extend([1, 2, 3]);
     /// assert_eq!(vec.capacity(), 10);
@@ -957,7 +956,7 @@ impl<T, A: Allocator> Vec<T, A> {
     /// assert!(vec.capacity() >= 3);
     /// ```
     #[cfg(not(no_global_oom_handling))]
-    #[unstable(feature = "shrink_to", reason = "new API", issue = "56431")]
+    #[stable(feature = "shrink_to", since = "1.56.0")]
     pub fn shrink_to(&mut self, min_capacity: usize) {
         if self.capacity() > min_capacity {
             self.buf.shrink_to_fit(cmp::max(self.len, min_capacity));

library/std/src/collections/hash/map.rs

@@ -667,7 +667,6 @@ where
     /// # Examples
     ///
     /// ```
-    /// #![feature(shrink_to)]
     /// use std::collections::HashMap;
     ///
     /// let mut map: HashMap<i32, i32> = HashMap::with_capacity(100);
@@ -680,7 +679,7 @@ where
     /// assert!(map.capacity() >= 2);
     /// ```
     #[inline]
-    #[unstable(feature = "shrink_to", reason = "new API", issue = "56431")]
+    #[stable(feature = "shrink_to", since = "1.56.0")]
     pub fn shrink_to(&mut self, min_capacity: usize) {
         self.base.shrink_to(min_capacity);
     }

library/std/src/collections/hash/set.rs

@@ -464,7 +464,6 @@ where
     /// # Examples
     ///
     /// ```
-    /// #![feature(shrink_to)]
     /// use std::collections::HashSet;
     ///
     /// let mut set = HashSet::with_capacity(100);
@@ -477,7 +476,7 @@ where
     /// assert!(set.capacity() >= 2);
     /// ```
     #[inline]
-    #[unstable(feature = "shrink_to", reason = "new API", issue = "56431")]
+    #[stable(feature = "shrink_to", since = "1.56.0")]
     pub fn shrink_to(&mut self, min_capacity: usize) {
         self.base.shrink_to(min_capacity)
     }

library/std/src/ffi/os_str.rs

@@ -321,7 +321,6 @@ impl OsString {
     /// # Examples
     ///
     /// ```
-    /// #![feature(shrink_to)]
     /// use std::ffi::OsString;
     ///
     /// let mut s = OsString::from("foo");
@@ -335,7 +334,7 @@ impl OsString {
     /// assert!(s.capacity() >= 3);
     /// ```
     #[inline]
-    #[unstable(feature = "shrink_to", reason = "new API", issue = "56431")]
+    #[stable(feature = "shrink_to", since = "1.56.0")]
     pub fn shrink_to(&mut self, min_capacity: usize) {
         self.inner.shrink_to(min_capacity)
     }

library/std/src/lib.rs

@@ -308,7 +308,6 @@
 #![feature(ptr_internals)]
 #![feature(rustc_attrs)]
 #![feature(rustc_private)]
-#![feature(shrink_to)]
 #![feature(slice_concat_ext)]
 #![feature(slice_internals)]
 #![feature(slice_ptr_get)]

library/std/src/path.rs

@@ -1398,7 +1398,7 @@ impl PathBuf {
     /// Invokes [`shrink_to`] on the underlying instance of [`OsString`].
     ///
     /// [`shrink_to`]: OsString::shrink_to
-    #[unstable(feature = "shrink_to", issue = "56431")]
+    #[stable(feature = "shrink_to", since = "1.56.0")]
     #[inline]
     pub fn shrink_to(&mut self, min_capacity: usize) {
         self.inner.shrink_to(min_capacity)