Rollup of 5 pull requests

src/liballoc/collections/btree/map.rs

@@ -2361,6 +2361,34 @@ impl<'a, K: Ord, V> Entry<'a, K, V> {
         }
     }
 
+    #[unstable(feature = "or_insert_with_key", issue = "71024")]
+    /// Ensures a value is in the entry by inserting, if empty, the result of the default function,
+    /// which takes the key as its argument, and returns a mutable reference to the value in the
+    /// entry.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// #![feature(or_insert_with_key)]
+    /// use std::collections::BTreeMap;
+    ///
+    /// let mut map: BTreeMap<&str, usize> = BTreeMap::new();
+    ///
+    /// map.entry("poneyland").or_insert_with_key(|key| key.chars().count());
+    ///
+    /// assert_eq!(map["poneyland"], 9);
+    /// ```
+    #[inline]
+    pub fn or_insert_with_key<F: FnOnce(&K) -> V>(self, default: F) -> &'a mut V {
+        match self {
+            Occupied(entry) => entry.into_mut(),
+            Vacant(entry) => {
+                let value = default(entry.key());
+                entry.insert(value)
+            }
+        }
+    }
+
     /// Returns a reference to this entry's key.
     ///
     /// # Examples

src/libcore/char/mod.rs

@@ -37,8 +37,6 @@ pub use self::decode::{decode_utf16, DecodeUtf16, DecodeUtf16Error};
 
 // unstable re-exports
 #[unstable(feature = "unicode_version", issue = "49726")]
-pub use crate::unicode::version::UnicodeVersion;
-#[unstable(feature = "unicode_version", issue = "49726")]
 pub use crate::unicode::UNICODE_VERSION;
 
 use crate::fmt::{self, Write};

src/libcore/unicode/mod.rs

@@ -3,19 +3,14 @@
 
 pub(crate) mod printable;
 mod unicode_data;
-pub(crate) mod version;
-
-use version::UnicodeVersion;
 
 /// The version of [Unicode](http://www.unicode.org/) that the Unicode parts of
 /// `char` and `str` methods are based on.
+///
+/// The version numbering scheme is explained in
+/// [Unicode 11.0 or later, Section 3.1 Versions of the Unicode Standard](https://www.unicode.org/versions/Unicode11.0.0/ch03.pdf#page=4).
 #[unstable(feature = "unicode_version", issue = "49726")]
-pub const UNICODE_VERSION: UnicodeVersion = UnicodeVersion {
-    major: unicode_data::UNICODE_VERSION.0,
-    minor: unicode_data::UNICODE_VERSION.1,
-    micro: unicode_data::UNICODE_VERSION.2,
-    _priv: (),
-};
+pub const UNICODE_VERSION: (u8, u8, u8) = unicode_data::UNICODE_VERSION;
 
 // For use in liballoc, not re-exported in libstd.
 pub mod derived_property {

src/libcore/unicode/unicode_data.rs

@@ -94,7 +94,7 @@ fn skip_search<const SOR: usize, const OFFSETS: usize>(
     offset_idx % 2 == 1
 }
 
-pub const UNICODE_VERSION: (u32, u32, u32) = (13, 0, 0);
+pub const UNICODE_VERSION: (u8, u8, u8) = (13, 0, 0);
 
 #[rustfmt::skip]
 pub mod alphabetic {