Auto merge of #30187 - alexcrichton:stabilize-1.6, r=aturon

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.
* `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

src/test/auxiliary/allocator-dummy.rs

@@ -10,7 +10,7 @@
 
 // no-prefer-dynamic
 
-#![feature(allocator, no_std, core, core_intrinsics, libc)]
+#![feature(allocator, core_intrinsics, libc)]
 #![allocator]
 #![crate_type = "rlib"]
 #![no_std]

src/test/auxiliary/allocator1.rs

@@ -10,7 +10,7 @@
 
 // no-prefer-dynamic
 
-#![feature(allocator, no_std, core)]
+#![feature(allocator)]
 #![allocator]
 #![crate_type = "rlib"]
 #![no_std]

src/test/auxiliary/allocator2.rs

@@ -10,7 +10,7 @@
 
 // no-prefer-dynamic
 
-#![feature(allocator, no_std, core)]
+#![feature(allocator)]
 #![allocator]
 #![crate_type = "rlib"]
 #![no_std]

src/test/auxiliary/allocator3.rs

@@ -10,7 +10,7 @@
 
 // no-prefer-dynamic
 
-#![feature(no_std, allocator)]
+#![feature(allocator)]
 #![no_std]
 #![allocator]
 #![crate_type = "rlib"]

src/test/auxiliary/lang-item-public.rs

@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#![feature(no_std, core, libc)]
+#![feature(libc)]
 #![no_std]
 #![feature(lang_items)]
 

src/test/auxiliary/needs_allocator.rs

@@ -10,7 +10,7 @@
 
 // no-prefer-dynamic
 
-#![feature(no_std, needs_allocator)]
+#![feature(needs_allocator)]
 #![no_std]
 #![needs_allocator]
 #![crate_type = "rlib"]

src/test/auxiliary/no_std_crate.rs

@@ -8,7 +8,6 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#![feature(no_std)]
 #![no_std]
 
 pub fn foo() {}

src/test/auxiliary/weak-lang-items.rs

@@ -13,7 +13,6 @@
 // This aux-file will require the eh_personality function to be codegen'd, but
 // it hasn't been defined just yet. Make sure we don't explode.
 
-#![feature(no_std)]
 #![no_std]
 #![crate_type = "rlib"]
 

src/test/compile-fail/cfg-attr-crate-2.rs

@@ -12,6 +12,6 @@
 
 // https://github.com/rust-lang/rust/issues/21833#issuecomment-72353044
 
-#![cfg_attr(broken, no_std)] //~ ERROR no_std is experimental
+#![cfg_attr(broken, no_core)] //~ ERROR no_core is experimental
 
 fn main() { }

src/test/compile-fail/derive-no-std-not-supported.rs

@@ -8,7 +8,6 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#![feature(no_std)]
 #![no_std]
 
 extern crate core;

src/test/compile-fail/fail-no-dead-code-core.rs

@@ -10,10 +10,9 @@
 
 #![deny(dead_code)]
 #![allow(unreachable_code)]
-#![feature(core)]
-
-#[macro_use] extern crate core;
 
+#[macro_use]
+extern crate core;
 
 fn foo() { //~ ERROR function is never used
 

src/test/compile-fail/gated-no-core.rs

@@ -8,6 +8,6 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#![no_std] //~ ERROR no_std is experimental
+#![no_core] //~ ERROR no_core is experimental
 
 fn main() {}

src/test/compile-fail/lint-dead-code-1.rs

@@ -8,7 +8,6 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#![feature(no_std)]
 #![no_std]
 #![allow(unused_variables)]
 #![allow(non_camel_case_types)]

src/test/compile-fail/no-std-inject.rs

@@ -8,7 +8,6 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#![feature(no_std, core)]
 #![no_std]
 
 extern crate core; //~ ERROR: an external crate named `core` has already

src/test/compile-fail/no_owned_box_lang_item.rs

@@ -12,8 +12,8 @@
 
 // error-pattern: requires `owned_box` lang_item
 
+#![feature(lang_items, box_syntax)]
 #![no_std]
-#![feature(lang_items, no_std, box_syntax)]
 
 fn main() {
     let x = box 1i32;

src/test/compile-fail/placement-expr-unstable.rs

@@ -11,7 +11,6 @@
 // Check that placement in respects unstable code checks.
 
 #![feature(placement_in_syntax)]
-#![feature(core)]
 
 extern crate core;
 

src/test/compile-fail/single-primitive-inherent-impl.rs

@@ -12,7 +12,6 @@
 
 #![crate_type = "lib"]
 #![feature(lang_items)]
-#![feature(no_std)]
 #![no_std]
 
 // OK

src/test/compile-fail/unused-attr.rs

@@ -10,7 +10,7 @@
 
 #![deny(unused_attributes)]
 #![allow(dead_code, unused_imports)]
-#![feature(core, custom_attribute)]
+#![feature(custom_attribute)]
 
 #![foo] //~ ERROR unused attribute
 

src/test/compile-fail/warn-pub-extern-crate.rs

@@ -8,11 +8,9 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// Check that `pub extern crate` gives a warning.
-
+#![feature(rustc_attrs)]
 
 pub extern crate core; //~WARN `pub extern crate` does not work
-//~^ ERROR core
 
-fn main() {
-}
+#[rustc_error]
+fn main() {} //~ ERROR: compilation successful

src/test/compile-fail/weak-lang-item.rs

@@ -12,7 +12,6 @@
 // error-pattern: language item required, but not found: `panic_fmt`
 // error-pattern: language item required, but not found: `eh_personality`
 
-#![feature(no_std)]
 #![no_std]
 
 extern crate core;

src/test/run-make/alloc-extern-crates/fakealloc.rs

@@ -9,10 +9,8 @@
 // except according to those terms.
 
 #![crate_type = "rlib"]
-#![feature(no_std)]
 #![no_std]
 
-
 #[inline]
 pub unsafe fn allocate(_size: usize, _align: usize) -> *mut u8 { 0 as *mut u8 }
 

src/test/run-make/no-duplicate-libs/bar.rs

@@ -8,9 +8,9 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#![feature(lang_items, no_std, libc)]
-#![no_std]
+#![feature(lang_items, libc)]
 #![crate_type = "dylib"]
+#![no_std]
 
 extern crate libc;
 

src/test/run-make/no-duplicate-libs/foo.rs

@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#![feature(lang_items, no_std, libc)]
+#![feature(lang_items, libc)]
 #![no_std]
 #![crate_type = "dylib"]
 

src/test/run-make/use-extern-for-plugins/foo.rs

@@ -8,7 +8,6 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#![feature(no_std)]
 #![no_std]
 #![crate_type = "lib"]
 #![crate_name = "a"]

src/test/run-pass/cfg-attr-crate.rs

@@ -12,6 +12,6 @@
 
 // pretty-expanded FIXME #23616
 
-#![cfg_attr(not_used, no_std)]
+#![cfg_attr(not_used, no_core)]
 
 fn main() { }

src/test/run-pass/derive-no-std.rs

@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#![feature(no_std, rand, collections, rustc_private)]
+#![feature(rand, collections, rustc_private)]
 #![no_std]
 
 extern crate rand;

src/test/run-pass/for-loop-no-std.rs

@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#![feature(lang_items, start, no_std, core_slice_ext, collections)]
+#![feature(lang_items, start, collections)]
 #![no_std]
 
 extern crate std as other;

src/test/run-pass/format-no-std.rs

@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#![feature(lang_items, start, no_std, collections)]
+#![feature(lang_items, start, collections)]
 #![no_std]
 
 extern crate std as other;

src/test/run-pass/issue-13655.rs

@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#![feature(unboxed_closures, core)]
+#![feature(fn_traits, unboxed_closures)]
 use std::ops::Fn;
 
 struct Foo<T>(T);

src/test/run-pass/issue-14958.rs

@@ -10,7 +10,7 @@
 
 // pretty-expanded FIXME #23616
 
-#![feature(unboxed_closures, core)]
+#![feature(fn_traits, unboxed_closures)]
 
 trait Foo { fn dummy(&self) { }}
 

src/test/run-pass/issue-14959.rs

@@ -10,7 +10,7 @@
 
 // pretty-expanded FIXME #23616
 
-#![feature(unboxed_closures, core)]
+#![feature(fn_traits, unboxed_closures)]
 
 use std::ops::Fn;
 

src/test/run-pass/issue-16739.rs

@@ -11,7 +11,7 @@
 
 #![allow(unknown_features)]
 #![feature(box_syntax)]
-#![feature(unboxed_closures, core)]
+#![feature(unboxed_closures, fn_traits)]
 
 // Test that unboxing shim for calling rust-call ABI methods through a
 // trait box works and does not cause an ICE.

src/test/run-pass/issue-18661.rs

@@ -13,10 +13,8 @@
 
 // pretty-expanded FIXME #23616
 
-#![feature(unboxed_closures, core)]
-
 pub fn inside<F: Fn()>(c: F) {
-    c.call(());
+    c();
 }
 
 // Use different number of type parameters and closure type to trigger

src/test/run-pass/issue-19098.rs

@@ -8,18 +8,13 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// pretty-expanded FIXME #23616
-
-#![feature(unboxed_closures, core)]
-
 pub trait Handler {
     fn handle(&self, &mut String);
 }
 
-impl<F> Handler for F
-where F: for<'a, 'b> Fn(&'a mut String) {
+impl<F> Handler for F where F: for<'a, 'b> Fn(&'a mut String) {
     fn handle(&self, st: &mut String) {
-        self.call((st,))
+        self(st)
     }
 }
 

src/test/run-pass/issue-19982.rs

@@ -10,7 +10,7 @@
 
 // pretty-expanded FIXME #23616
 
-#![feature(core,unboxed_closures)]
+#![feature(fn_traits, unboxed_closures)]
 
 #[allow(dead_code)]
 struct Foo;

src/test/run-pass/issue-20544.rs

@@ -9,7 +9,7 @@
 // except according to those terms.
 
 #![feature(unboxed_closures)]
-#![feature(core)]
+#![feature(fn_traits)]
 
 struct Fun<F>(F);
 

src/test/run-pass/last-use-in-cap-clause.rs

@@ -10,21 +10,15 @@
 
 // Make sure #1399 stays fixed
 
-
-#![allow(unknown_features)]
-#![feature(box_syntax)]
-#![feature(unboxed_closures, core)]
-
 struct A { a: Box<isize> }
 
 fn foo() -> Box<FnMut() -> isize + 'static> {
-    let k: Box<_> = box 22;
+    let k: Box<_> = Box::new(22);
     let _u = A {a: k.clone()};
     let result  = || 22;
-    // FIXME (#22405): Replace `Box::new` with `box` here when/if possible.
     Box::new(result)
 }
 
 pub fn main() {
-    assert_eq!(foo().call_mut(()), 22);
+    assert_eq!(foo()(), 22);
 }

src/test/run-pass/no-std-1.rs

@@ -8,7 +8,6 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#![feature(no_std)]
 #![no_std]
 
 extern crate std;

src/test/run-pass/no-std-2.rs

@@ -8,7 +8,6 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#![feature(no_std)]
 #![no_std]
 
 extern crate std;

src/test/run-pass/no-std-3.rs

@@ -8,7 +8,6 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#![feature(no_std)]
 #![no_std]
 
 extern crate std;

src/test/run-pass/overloaded-calls-param-vtables.rs

@@ -12,7 +12,7 @@
 
 // pretty-expanded FIXME #23616
 
-#![feature(unboxed_closures, core)]
+#![feature(unboxed_closures, fn_traits)]
 
 use std::marker::PhantomData;
 use std::ops::Fn;

src/test/run-pass/overloaded-calls-simple.rs

@@ -9,7 +9,7 @@
 // except according to those terms.
 
 
-#![feature(lang_items, unboxed_closures, core)]
+#![feature(lang_items, unboxed_closures, fn_traits)]
 
 use std::ops::{Fn, FnMut, FnOnce};
 

src/test/run-pass/overloaded-calls-zero-args.rs

@@ -9,7 +9,7 @@
 // except according to those terms.
 
 
-#![feature(unboxed_closures, core)]
+#![feature(unboxed_closures, fn_traits)]
 
 use std::ops::FnMut;
 

src/test/run-pass/regions-copy-closure.rs

@@ -8,10 +8,6 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-
-#![allow(unknown_features)]
-#![feature(unboxed_closures, core)]
-
 struct closure_box<'a> {
     cl: Box<FnMut() + 'a>,
 }
@@ -25,9 +21,8 @@ pub fn main() {
     assert_eq!(i, 3);
     {
         let cl = || i += 1;
-        // FIXME (#22405): Replace `Box::new` with `box` here when/if possible.
         let mut cl_box = box_it(Box::new(cl));
-        cl_box.cl.call_mut(());
+        (cl_box.cl)();
     }
     assert_eq!(i, 4);
 }

src/test/run-pass/regions-static-closure.rs

@@ -8,10 +8,6 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#![allow(unknown_features)]
-#![feature(box_syntax)]
-#![feature(unboxed_closures, core)]
-
 struct closure_box<'a> {
     cl: Box<FnMut() + 'a>,
 }
@@ -21,11 +17,10 @@ fn box_it<'a>(x: Box<FnMut() + 'a>) -> closure_box<'a> {
 }
 
 fn call_static_closure(mut cl: closure_box<'static>) {
-    cl.cl.call_mut(())
+    (cl.cl)();
 }
 
 pub fn main() {
-    // FIXME (#22405): Replace `Box::new` with `box` here when/if possible.
     let cl_box = box_it(Box::new(|| println!("Hello, world!")));
     call_static_closure(cl_box);
 }

src/test/run-pass/unboxed-closures-extern-fn-hr.rs

@@ -10,11 +10,6 @@
 
 // Checks that higher-ranked extern fn pointers implement the full range of Fn traits.
 
-
-#![feature(unboxed_closures, core)]
-
-use std::ops::{Fn,FnMut,FnOnce};
-
 fn square(x: &isize) -> isize { (*x) * (*x) }
 
 fn call_it<F:Fn(&isize)->isize>(f: &F, x: isize) -> isize {
@@ -22,7 +17,7 @@ fn call_it<F:Fn(&isize)->isize>(f: &F, x: isize) -> isize {
 }
 
 fn call_it_boxed(f: &Fn(&isize) -> isize, x: isize) -> isize {
-    f.call((&x,))
+    f(&x)
 }
 
 fn call_it_mut<F:FnMut(&isize)->isize>(f: &mut F, x: isize) -> isize {

src/test/run-pass/unboxed-closures-fn-as-fnmut-and-fnonce.rs

@@ -12,7 +12,7 @@
 // any Fn trait to be used where Fn is implemented.
 
 
-#![feature(unboxed_closures, core)]
+#![feature(unboxed_closures, fn_traits)]
 
 use std::ops::{Fn,FnMut,FnOnce};
 

src/test/run-pass/unboxed-closures-fnmut-as-fnonce.rs

@@ -12,9 +12,7 @@
 // FnMut or FnOnce to be used where FnMut is implemented.
 
 
-#![feature(unboxed_closures, core)]
-
-use std::ops::{FnMut,FnOnce};
+#![feature(unboxed_closures, fn_traits)]
 
 struct S;
 

src/test/run-pass/unboxed-closures-infer-recursive-fn.rs

@@ -8,8 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-
-#![feature(core,unboxed_closures)]
+#![feature(fn_traits, unboxed_closures)]
 
 use std::marker::PhantomData;
 

src/test/run-pass/unboxed-closures-manual-impl.rs

@@ -8,10 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-
-#![feature(unboxed_closures, core)]
-
-use std::ops::FnMut;
+#![feature(unboxed_closures, fn_traits)]
 
 struct S;
 

src/test/run-pass/unboxed-closures-monomorphization.rs

@@ -11,30 +11,25 @@
 // Test that unboxed closures in contexts with free type parameters
 // monomorphize correctly (issue #16791)
 
-#![allow(unknown_features)]
-#![feature(box_syntax)]
-#![feature(unboxed_closures, core)]
-
 fn main(){
     fn bar<'a, T:Clone+'a> (t: T) -> Box<FnMut()->T + 'a> {
-        // FIXME (#22405): Replace `Box::new` with `box` here when/if possible.
         Box::new(move || t.clone())
     }
 
     let mut f = bar(42_u32);
-    assert_eq!(f.call_mut(()), 42);
+    assert_eq!(f(), 42);
 
     let mut f = bar("forty-two");
-    assert_eq!(f.call_mut(()), "forty-two");
+    assert_eq!(f(), "forty-two");
 
     let x = 42_u32;
     let mut f = bar(&x);
-    assert_eq!(f.call_mut(()), &x);
+    assert_eq!(f(), &x);
 
     #[derive(Clone, Copy, Debug, PartialEq)]
     struct Foo(usize, &'static str);
 
     let x = Foo(42, "forty-two");
     let mut f = bar(x);
-    assert_eq!(f.call_mut(()), x);
+    assert_eq!(f(), x);
 }

src/test/run-pass/unboxed-closures-prelude.rs

@@ -12,14 +12,9 @@
 
 // pretty-expanded FIXME #23616
 
-#![allow(unknown_features)]
-#![feature(box_syntax)]
-#![feature(unboxed_closures, core)]
-
 fn main() {
-    // FIXME (#22405): Replace `Box::new` with `box` here when/if possible.
     let task: Box<Fn(isize) -> isize> = Box::new(|x| x);
-    task.call((0, ));
+    task(0);
 
     let mut task: Box<FnMut(isize) -> isize> = Box::new(|x| x);
     task(0);

src/test/run-pass/vec-macro-no-std.rs

@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#![feature(lang_items, start, no_std, core_slice_ext, libc, collections)]
+#![feature(lang_items, start, libc, collections)]
 #![no_std]
 
 extern crate std as other;
@@ -18,8 +18,6 @@ extern crate libc;
 #[macro_use]
 extern crate collections;
 
-use core::option::Option::Some;
-use core::slice::SliceExt;
 use collections::vec::Vec;
 
 // Issue #16806

src/test/rustdoc/issue-15318.rs

@@ -11,7 +11,6 @@
 // aux-build:issue-15318.rs
 // ignore-cross-compile
 
-#![feature(no_std)]
 #![no_std]
 
 extern crate issue_15318;

src/test/rustdoc/issue-23511.rs

@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#![feature(no_std, lang_items, core)]
+#![feature(lang_items)]
 #![no_std]
 
 pub mod str {