std: Stabilize APIs for the 1.6 release

This commit is the standard API stabilization commit for the 1.6 release cycle.
The list of issues and APIs below have all been through their cycle-long FCP and
the libs team decisions are listed below

Stabilized APIs

* `Read::read_exact`
* `ErrorKind::UnexpectedEof` (renamed from `UnexpectedEOF`)
* libcore -- this was a bit of a nuanced stabilization, the crate itself is now
  marked as `#[stable]` and the methods appearing via traits for primitives like
  `char` and `str` are now also marked as stable. Note that the extension traits
  themeselves are marked as unstable as they're imported via the prelude. The
  `try!` macro was also moved from the standard library into libcore to have the
  same interface. Otherwise the functions all have copied stability from the
  standard library now.
* The `#![no_std]` attribute
* `fs::DirBuilder`
* `fs::DirBuilder::new`
* `fs::DirBuilder::recursive`
* `fs::DirBuilder::create`
* `os::unix::fs::DirBuilderExt`
* `os::unix::fs::DirBuilderExt::mode`
* `vec::Drain`
* `vec::Vec::drain`
* `string::Drain`
* `string::String::drain`
* `vec_deque::Drain`
* `vec_deque::VecDeque::drain`
* `collections::hash_map::Drain`
* `collections::hash_map::HashMap::drain`
* `collections::hash_set::Drain`
* `collections::hash_set::HashSet::drain`
* `collections::binary_heap::Drain`
* `collections::binary_heap::BinaryHeap::drain`
* `Vec::extend_from_slice` (renamed from `push_all`)
* `Mutex::get_mut`
* `Mutex::into_inner`
* `RwLock::get_mut`
* `RwLock::into_inner`
* `Iterator::min_by_key` (renamed from `min_by`)
* `Iterator::max_by_key` (renamed from `max_by`)

Deprecated APIs

* `ErrorKind::UnexpectedEOF` (renamed to `UnexpectedEof`)
* `OsString::from_bytes`
* `OsStr::to_cstring`
* `OsStr::to_bytes`
* `fs::walk_dir` and `fs::WalkDir`
* `path::Components::peek`
* `slice::bytes::MutableByteVector`
* `slice::bytes::copy_memory`
* `Vec::push_all` (renamed to `extend_from_slice`)
* `Duration::span`
* `IpAddr`
* `SocketAddr::ip`
* `Read::tee`
* `io::Tee`
* `Write::broadcast`
* `io::Broadcast`
* `Iterator::min_by` (renamed to `min_by_key`)
* `Iterator::max_by` (renamed to `max_by_key`)
* `net::lookup_addr`

New APIs (still unstable)

* `<[T]>::sort_by_key` (added to mirror `min_by_key`)

Closes #27585
Closes #27704
Closes #27707
Closes #27710
Closes #27711
Closes #27727
Closes #27740
Closes #27744
Closes #27799
Closes #27801
cc #27801 (doesn't close as `Chars` is still unstable)
Closes #28968

2 files changed, 3 insertions, 11 deletions

diff --git a/src/libstd/collections/hash/map.rs b/src/libstd/collections/hash/map.rs
index c8b377ba3be..77c4149f992 100644
--- a/src/libstd/collections/hash/map.rs
+++ b/src/libstd/collections/hash/map.rs
@@ -986,8 +986,6 @@ impl<K, V, S> HashMap<K, V, S>
     /// # Examples
     ///
     /// ```
-    /// #![feature(drain)]
-    ///
     /// use std::collections::HashMap;
     ///
     /// let mut a = HashMap::new();
@@ -1002,9 +1000,7 @@ impl<K, V, S> HashMap<K, V, S>
     /// assert!(a.is_empty());
     /// ```
     #[inline]
-    #[unstable(feature = "drain",
-               reason = "matches collection reform specification, waiting for dust to settle",
-               issue = "27711")]
+    #[stable(feature = "drain", since = "1.6.0")]
     pub fn drain(&mut self) -> Drain<K, V> {
         fn last_two<A, B, C>((_, b, c): (A, B, C)) -> (B, C) { (b, c) }
         let last_two: fn((SafeHash, K, V)) -> (K, V) = last_two; // coerce to fn pointer
@@ -1327,9 +1323,7 @@ impl<'a, K, V> Clone for Values<'a, K, V> {
 }
 
 /// HashMap drain iterator.
-#[unstable(feature = "drain",
-           reason = "matches collection reform specification, waiting for dust to settle",
-           issue = "27711")]
+#[stable(feature = "drain", since = "1.6.0")]
 pub struct Drain<'a, K: 'a, V: 'a> {
     inner: iter::Map<table::Drain<'a, K, V>, fn((SafeHash, K, V)) -> (K, V)>
 }
diff --git a/src/libstd/collections/hash/set.rs b/src/libstd/collections/hash/set.rs
index daabb0f9fa8..08f356463bc 100644
--- a/src/libstd/collections/hash/set.rs
+++ b/src/libstd/collections/hash/set.rs
@@ -413,9 +413,7 @@ impl<T, S> HashSet<T, S>
 
     /// Clears the set, returning all elements in an iterator.
     #[inline]
-    #[unstable(feature = "drain",
-               reason = "matches collection reform specification, waiting for dust to settle",
-               issue = "27711")]
+    #[stable(feature = "drain", since = "1.6.0")]
     pub fn drain(&mut self) -> Drain<T> {
         fn first<A, B>((a, _): (A, B)) -> A { a }
         let first: fn((T, ())) -> T = first; // coerce to fn pointer