From 7aaec26b2f11579e406ef18f42d8ef7b3def819c Mon Sep 17 00:00:00 2001 From: Miguel Ojeda Date: Thu, 2 Dec 2021 17:46:55 +0100 Subject: [PATCH] rust: alloc: upgrade to 1.57.0 Signed-off-by: Miguel Ojeda --- rust/alloc/alloc.rs | 1 - rust/alloc/borrow.rs | 6 +- rust/alloc/boxed.rs | 55 +++++++++++++ .../collections/btree/dedup_sorted_iter.rs | 47 +++++++++++ rust/alloc/collections/mod.rs | 4 +- rust/alloc/fmt.rs | 28 +++---- rust/alloc/lib.rs | 18 ++++- rust/alloc/prelude/mod.rs | 17 ---- rust/alloc/prelude/v1.rs | 16 ---- rust/alloc/raw_vec.rs | 5 +- rust/alloc/slice.rs | 4 + rust/alloc/str.rs | 7 ++ rust/alloc/string.rs | 68 +++++++++------- rust/alloc/vec/drain.rs | 1 + rust/alloc/vec/into_iter.rs | 59 +++++++++++++- rust/alloc/vec/mod.rs | 80 +++++++++++++------ 16 files changed, 303 insertions(+), 113 deletions(-) create mode 100644 rust/alloc/collections/btree/dedup_sorted_iter.rs delete mode 100644 rust/alloc/prelude/mod.rs delete mode 100644 rust/alloc/prelude/v1.rs diff --git a/rust/alloc/alloc.rs b/rust/alloc/alloc.rs index 1e6746ff316a05..4a0c85dde928fd 100644 --- a/rust/alloc/alloc.rs +++ b/rust/alloc/alloc.rs @@ -309,7 +309,6 @@ unsafe impl Allocator for Global { } /// The allocator for unique pointers. -// This function must not unwind. If it does, MIR codegen will fail. #[cfg(all(not(no_global_oom_handling), not(test)))] #[lang = "exchange_malloc"] #[inline] diff --git a/rust/alloc/borrow.rs b/rust/alloc/borrow.rs index 3a052642745659..7885168b81bafb 100644 --- a/rust/alloc/borrow.rs +++ b/rust/alloc/borrow.rs @@ -332,7 +332,11 @@ impl Cow<'_, B> { } #[stable(feature = "rust1", since = "1.0.0")] -impl Deref for Cow<'_, B> { +#[rustc_const_unstable(feature = "const_deref", issue = "88955")] +impl const Deref for Cow<'_, B> +where + B::Owned: ~const Borrow, +{ type Target = B; fn deref(&self) -> &B { diff --git a/rust/alloc/boxed.rs b/rust/alloc/boxed.rs index f74443470b17d4..ffaa9c5459f272 100644 --- a/rust/alloc/boxed.rs +++ b/rust/alloc/boxed.rs @@ -189,6 +189,7 @@ impl Box { #[cfg(not(no_global_oom_handling))] #[inline(always)] #[stable(feature = "rust1", since = "1.0.0")] + #[must_use] pub fn new(x: T) -> Self { box x } @@ -213,6 +214,7 @@ impl Box { /// ``` #[cfg(not(no_global_oom_handling))] #[unstable(feature = "new_uninit", issue = "63291")] + #[must_use] #[inline] pub fn new_uninit() -> Box> { Self::new_uninit_in(Global) @@ -239,6 +241,7 @@ impl Box { #[cfg(not(no_global_oom_handling))] #[inline] #[unstable(feature = "new_uninit", issue = "63291")] + #[must_use] pub fn new_zeroed() -> Box> { Self::new_zeroed_in(Global) } @@ -247,6 +250,7 @@ impl Box { /// `x` will be pinned in memory and unable to be moved. #[cfg(not(no_global_oom_handling))] #[stable(feature = "pin", since = "1.33.0")] + #[must_use] #[inline(always)] pub fn pin(x: T) -> Pin> { (box x).into() @@ -341,6 +345,7 @@ impl Box { /// ``` #[cfg(not(no_global_oom_handling))] #[unstable(feature = "allocator_api", issue = "32838")] + #[must_use] #[inline] pub fn new_in(x: T, alloc: A) -> Self { let mut boxed = Self::new_uninit_in(alloc); @@ -397,6 +402,7 @@ impl Box { /// ``` #[unstable(feature = "allocator_api", issue = "32838")] #[cfg(not(no_global_oom_handling))] + #[must_use] // #[unstable(feature = "new_uninit", issue = "63291")] pub fn new_uninit_in(alloc: A) -> Box, A> { let layout = Layout::new::>(); @@ -461,6 +467,7 @@ impl Box { #[unstable(feature = "allocator_api", issue = "32838")] #[cfg(not(no_global_oom_handling))] // #[unstable(feature = "new_uninit", issue = "63291")] + #[must_use] pub fn new_zeroed_in(alloc: A) -> Box, A> { let layout = Layout::new::>(); // NOTE: Prefer match over unwrap_or_else since closure sometimes not inlineable. @@ -505,6 +512,7 @@ impl Box { /// `x` will be pinned in memory and unable to be moved. #[cfg(not(no_global_oom_handling))] #[unstable(feature = "allocator_api", issue = "32838")] + #[must_use] #[inline(always)] pub fn pin_in(x: T, alloc: A) -> Pin where @@ -563,6 +571,7 @@ impl Box<[T]> { /// ``` #[cfg(not(no_global_oom_handling))] #[unstable(feature = "new_uninit", issue = "63291")] + #[must_use] pub fn new_uninit_slice(len: usize) -> Box<[mem::MaybeUninit]> { unsafe { RawVec::with_capacity(len).into_box(len) } } @@ -587,6 +596,7 @@ impl Box<[T]> { /// [zeroed]: mem::MaybeUninit::zeroed #[cfg(not(no_global_oom_handling))] #[unstable(feature = "new_uninit", issue = "63291")] + #[must_use] pub fn new_zeroed_slice(len: usize) -> Box<[mem::MaybeUninit]> { unsafe { RawVec::with_capacity_zeroed(len).into_box(len) } } @@ -683,6 +693,7 @@ impl Box<[T], A> { #[cfg(not(no_global_oom_handling))] #[unstable(feature = "allocator_api", issue = "32838")] // #[unstable(feature = "new_uninit", issue = "63291")] + #[must_use] pub fn new_uninit_slice_in(len: usize, alloc: A) -> Box<[mem::MaybeUninit], A> { unsafe { RawVec::with_capacity_in(len, alloc).into_box(len) } } @@ -710,6 +721,7 @@ impl Box<[T], A> { #[cfg(not(no_global_oom_handling))] #[unstable(feature = "allocator_api", issue = "32838")] // #[unstable(feature = "new_uninit", issue = "63291")] + #[must_use] pub fn new_zeroed_slice_in(len: usize, alloc: A) -> Box<[mem::MaybeUninit], A> { unsafe { RawVec::with_capacity_zeroed_in(len, alloc).into_box(len) } } @@ -1088,6 +1100,7 @@ unsafe impl<#[may_dangle] T: ?Sized, A: Allocator> Drop for Box { } } +#[cfg(not(no_global_oom_handling))] #[stable(feature = "rust1", since = "1.0.0")] impl Default for Box { /// Creates a `Box`, with the `Default` value for T. @@ -1278,6 +1291,7 @@ impl From for Box { /// from the stack into it. /// /// # Examples + /// /// ```rust /// let x = 5; /// let boxed = Box::new(5); @@ -1331,6 +1345,12 @@ impl From<&[T]> for Box<[T]> { #[cfg(not(no_global_oom_handling))] #[stable(feature = "box_from_cow", since = "1.45.0")] impl From> for Box<[T]> { + /// Converts a `Cow<'_, [T]>` into a `Box<[T]>` + /// + /// When `cow` is the `Cow::Borrowed` variant, this + /// conversion allocates on the heap and copies the + /// underlying slice. Otherwise, it will try to reuse the owned + /// `Vec`'s allocation. #[inline] fn from(cow: Cow<'_, [T]>) -> Box<[T]> { match cow { @@ -1349,6 +1369,7 @@ impl From<&str> for Box { /// and performs a copy of `s`. /// /// # Examples + /// /// ```rust /// let boxed: Box = Box::from("hello"); /// println!("{}", boxed); @@ -1362,6 +1383,29 @@ impl From<&str> for Box { #[cfg(not(no_global_oom_handling))] #[stable(feature = "box_from_cow", since = "1.45.0")] impl From> for Box { + /// Converts a `Cow<'_, str>` into a `Box` + /// + /// When `cow` is the `Cow::Borrowed` variant, this + /// conversion allocates on the heap and copies the + /// underlying `str`. Otherwise, it will try to reuse the owned + /// `String`'s allocation. + /// + /// # Examples + /// + /// ```rust + /// use std::borrow::Cow; + /// + /// let unboxed = Cow::Borrowed("hello"); + /// let boxed: Box = Box::from(unboxed); + /// println!("{}", boxed); + /// ``` + /// + /// ```rust + /// # use std::borrow::Cow; + /// let unboxed = Cow::Owned("hello".to_string()); + /// let boxed: Box = Box::from(unboxed); + /// println!("{}", boxed); + /// ``` #[inline] fn from(cow: Cow<'_, str>) -> Box { match cow { @@ -1396,6 +1440,7 @@ impl From> for Box<[u8], A> { } } +#[cfg(not(no_global_oom_handling))] #[stable(feature = "box_from_array", since = "1.45.0")] impl From<[T; N]> for Box<[T]> { /// Converts a `[T; N]` into a `Box<[T]>` @@ -1403,6 +1448,7 @@ impl From<[T; N]> for Box<[T]> { /// This conversion moves the array to newly heap-allocated memory. /// /// # Examples + /// /// ```rust /// let boxed: Box<[u8]> = Box::from([4, 2]); /// println!("{:?}", boxed); @@ -1416,6 +1462,15 @@ impl From<[T; N]> for Box<[T]> { impl TryFrom> for Box<[T; N]> { type Error = Box<[T]>; + /// Attempts to convert a `Box<[T]>` into a `Box<[T; N]>`. + /// + /// The conversion occurs in-place and does not require a + /// new memory allocation. + /// + /// # Errors + /// + /// Returns the old `Box<[T]>` in the `Err` variant if + /// `boxed_slice.len()` does not equal `N`. fn try_from(boxed_slice: Box<[T]>) -> Result { if boxed_slice.len() == N { Ok(unsafe { Box::from_raw(Box::into_raw(boxed_slice) as *mut [T; N]) }) diff --git a/rust/alloc/collections/btree/dedup_sorted_iter.rs b/rust/alloc/collections/btree/dedup_sorted_iter.rs new file mode 100644 index 00000000000000..60bf83b8387c38 --- /dev/null +++ b/rust/alloc/collections/btree/dedup_sorted_iter.rs @@ -0,0 +1,47 @@ +use core::iter::Peekable; + +/// A iterator for deduping the key of a sorted iterator. +/// When encountering the duplicated key, only the last key-value pair is yielded. +/// +/// Used by [`BTreeMap::bulk_build_from_sorted_iter`]. +pub struct DedupSortedIter +where + I: Iterator, +{ + iter: Peekable, +} + +impl DedupSortedIter +where + I: Iterator, +{ + pub fn new(iter: I) -> Self { + Self { iter: iter.peekable() } + } +} + +impl Iterator for DedupSortedIter +where + K: Eq, + I: Iterator, +{ + type Item = (K, V); + + fn next(&mut self) -> Option<(K, V)> { + loop { + let next = match self.iter.next() { + Some(next) => next, + None => return None, + }; + + let peeked = match self.iter.peek() { + Some(peeked) => peeked, + None => return Some(next), + }; + + if next.0 != peeked.0 { + return Some(next); + } + } + } +} diff --git a/rust/alloc/collections/mod.rs b/rust/alloc/collections/mod.rs index dde47be448d0bd..ab83867b985ad8 100644 --- a/rust/alloc/collections/mod.rs +++ b/rust/alloc/collections/mod.rs @@ -59,7 +59,7 @@ use core::fmt::Display; /// The error type for `try_reserve` methods. #[derive(Clone, PartialEq, Eq, Debug)] -#[unstable(feature = "try_reserve", reason = "new API", issue = "48043")] +#[stable(feature = "try_reserve", since = "1.57.0")] pub struct TryReserveError { kind: TryReserveErrorKind, } @@ -128,7 +128,7 @@ impl From for TryReserveErrorKind { } } -#[unstable(feature = "try_reserve", reason = "new API", issue = "48043")] +#[stable(feature = "try_reserve", since = "1.57.0")] impl Display for TryReserveError { fn fmt( &self, diff --git a/rust/alloc/fmt.rs b/rust/alloc/fmt.rs index b467881a6f3a98..6a3fadcaf5dd65 100644 --- a/rust/alloc/fmt.rs +++ b/rust/alloc/fmt.rs @@ -350,7 +350,7 @@ //! provides some helper methods. //! //! Additionally, the return value of this function is [`fmt::Result`] which is a -//! type alias of [`Result`]`<(), `[`std::fmt::Error`]`>`. Formatting implementations +//! type alias of [Result]<(), [std::fmt::Error]>. Formatting implementations //! should ensure that they propagate errors from the [`Formatter`] (e.g., when //! calling [`write!`]). However, they should never return errors spuriously. That //! is, a formatting implementation must and may only return an error if the @@ -507,23 +507,19 @@ //! it would internally pass around this structure until it has been determined //! where output should go to. //! -//! [`fmt::Result`]: Result -//! [`Result`]: core::result::Result -//! [`std::fmt::Error`]: Error -//! [`write!`]: core::write -//! [`write`]: core::write -//! [`format!`]: crate::format -//! [`to_string`]: crate::string::ToString -//! [`writeln!`]: core::writeln +//! [`fmt::Result`]: Result "fmt::Result" +//! [Result]: core::result::Result "std::result::Result" +//! [std::fmt::Error]: Error "fmt::Error" +//! [`write`]: write() "fmt::write" +//! [`to_string`]: crate::string::ToString::to_string "ToString::to_string" //! [`write_fmt`]: ../../std/io/trait.Write.html#method.write_fmt //! [`std::io::Write`]: ../../std/io/trait.Write.html -//! [`print!`]: ../../std/macro.print.html -//! [`println!`]: ../../std/macro.println.html -//! [`eprint!`]: ../../std/macro.eprint.html -//! [`eprintln!`]: ../../std/macro.eprintln.html -//! [`format_args!`]: core::format_args -//! [`fmt::Arguments`]: Arguments -//! [`format`]: crate::format +//! [`print!`]: ../../std/macro.print.html "print!" +//! [`println!`]: ../../std/macro.println.html "println!" +//! [`eprint!`]: ../../std/macro.eprint.html "eprint!" +//! [`eprintln!`]: ../../std/macro.eprintln.html "eprintln!" +//! [`fmt::Arguments`]: Arguments "fmt::Arguments" +//! [`format`]: format() "fmt::format" #![stable(feature = "rust1", since = "1.0.0")] diff --git a/rust/alloc/lib.rs b/rust/alloc/lib.rs index 6cf622ba39e0a5..713d7b992b1799 100644 --- a/rust/alloc/lib.rs +++ b/rust/alloc/lib.rs @@ -69,6 +69,17 @@ issue_tracker_base_url = "https://github.com/rust-lang/rust/issues/", test(no_crate_inject, attr(allow(unused_variables), deny(warnings))) )] +#![cfg_attr( + not(bootstrap), + doc(cfg_hide( + not(test), + not(any(test, bootstrap)), + any(not(feature = "miri-test-libstd"), test, doctest), + no_global_oom_handling, + not(no_global_oom_handling), + target_has_atomic = "ptr" + )) +)] #![no_std] #![needs_allocator] #![warn(deprecated_in_future)] @@ -87,7 +98,6 @@ #![feature(allow_internal_unstable)] #![feature(arbitrary_self_types)] #![feature(async_stream)] -#![cfg_attr(bootstrap, feature(bindings_after_at))] #![feature(box_patterns)] #![feature(box_syntax)] #![feature(cfg_sanitize)] @@ -114,6 +124,7 @@ // that the feature-gate isn't enabled. Ideally, it wouldn't check for the feature gate for docs // from other crates, but since this can only appear for lang items, it doesn't seem worth fixing. #![feature(intra_doc_pointers)] +#![feature(iter_advance_by)] #![feature(iter_zip)] #![feature(lang_items)] #![feature(layout_for_ptr)] @@ -145,11 +156,11 @@ #![feature(alloc_layout_extra)] #![feature(trusted_random_access)] #![feature(try_trait_v2)] -#![cfg_attr(bootstrap, feature(min_type_alias_impl_trait))] -#![cfg_attr(not(bootstrap), feature(type_alias_impl_trait))] #![feature(associated_type_bounds)] #![feature(slice_group_by)] #![feature(decl_macro)] +#![feature(doc_cfg)] +#![cfg_attr(not(bootstrap), feature(doc_cfg_hide))] // Allow testing this library #[cfg(test)] @@ -180,7 +191,6 @@ mod boxed { pub mod borrow; pub mod collections; pub mod fmt; -pub mod prelude; pub mod raw_vec; #[cfg(not(no_rc))] pub mod rc; diff --git a/rust/alloc/prelude/mod.rs b/rust/alloc/prelude/mod.rs deleted file mode 100644 index a64a1843760ebd..00000000000000 --- a/rust/alloc/prelude/mod.rs +++ /dev/null @@ -1,17 +0,0 @@ -// SPDX-License-Identifier: Apache-2.0 OR MIT - -//! The alloc Prelude -//! -//! The purpose of this module is to alleviate imports of commonly-used -//! items of the `alloc` crate by adding a glob import to the top of modules: -//! -//! ``` -//! # #![allow(unused_imports)] -//! #![feature(alloc_prelude)] -//! extern crate alloc; -//! use alloc::prelude::v1::*; -//! ``` - -#![unstable(feature = "alloc_prelude", issue = "58935")] - -pub mod v1; diff --git a/rust/alloc/prelude/v1.rs b/rust/alloc/prelude/v1.rs deleted file mode 100644 index 48d75431c0d132..00000000000000 --- a/rust/alloc/prelude/v1.rs +++ /dev/null @@ -1,16 +0,0 @@ -// SPDX-License-Identifier: Apache-2.0 OR MIT - -//! The first version of the prelude of `alloc` crate. -//! -//! See the [module-level documentation](../index.html) for more. - -#![unstable(feature = "alloc_prelude", issue = "58935")] - -#[unstable(feature = "alloc_prelude", issue = "58935")] -pub use crate::borrow::ToOwned; -#[unstable(feature = "alloc_prelude", issue = "58935")] -pub use crate::boxed::Box; -#[unstable(feature = "alloc_prelude", issue = "58935")] -pub use crate::string::{String, ToString}; -#[unstable(feature = "alloc_prelude", issue = "58935")] -pub use crate::vec::Vec; diff --git a/rust/alloc/raw_vec.rs b/rust/alloc/raw_vec.rs index 576660a87374ae..ac86e0f63dd9a1 100644 --- a/rust/alloc/raw_vec.rs +++ b/rust/alloc/raw_vec.rs @@ -71,6 +71,7 @@ impl RawVec { /// `RawVec` with capacity `0`. If `T` is zero-sized, then it makes a /// `RawVec` with capacity `usize::MAX`. Useful for implementing /// delayed allocation. + #[must_use] pub const fn new() -> Self { Self::new_in(Global) } @@ -89,6 +90,7 @@ impl RawVec { /// /// Aborts on OOM. #[cfg(not(no_global_oom_handling))] + #[must_use] #[inline] pub fn with_capacity(capacity: usize) -> Self { Self::with_capacity_in(capacity, Global) @@ -106,6 +108,7 @@ impl RawVec { /// Like `with_capacity`, but guarantees the buffer is zeroed. #[cfg(not(no_global_oom_handling))] + #[must_use] #[inline] pub fn with_capacity_zeroed(capacity: usize) -> Self { Self::with_capacity_zeroed_in(capacity, Global) @@ -362,7 +365,7 @@ impl RawVec { pub fn reserve(&mut self, len: usize, additional: usize) { // Callers expect this function to be very cheap when there is already sufficient capacity. // Therefore, we move all the resizing and error-handling logic from grow_amortized and - // handle_reserve behind a call, while making sure that the this function is likely to be + // handle_reserve behind a call, while making sure that this function is likely to be // inlined as just a comparison and a call if the comparison fails. #[cold] fn do_reserve_and_handle( diff --git a/rust/alloc/slice.rs b/rust/alloc/slice.rs index 9afb8f3caf11f3..ddb86eca86c89c 100644 --- a/rust/alloc/slice.rs +++ b/rust/alloc/slice.rs @@ -753,6 +753,8 @@ impl [u8] { /// /// [`make_ascii_uppercase`]: slice::make_ascii_uppercase #[cfg(not(no_global_oom_handling))] + #[must_use = "this returns the uppercase bytes as a new Vec, \ + without modifying the original"] #[stable(feature = "ascii_methods_on_intrinsics", since = "1.23.0")] #[inline] pub fn to_ascii_uppercase(&self) -> Vec { @@ -771,6 +773,8 @@ impl [u8] { /// /// [`make_ascii_lowercase`]: slice::make_ascii_lowercase #[cfg(not(no_global_oom_handling))] + #[must_use = "this returns the lowercase bytes as a new Vec, \ + without modifying the original"] #[stable(feature = "ascii_methods_on_intrinsics", since = "1.23.0")] #[inline] pub fn to_ascii_lowercase(&self) -> Vec { diff --git a/rust/alloc/str.rs b/rust/alloc/str.rs index fa5e3b55ad209c..29b4aa31745ad2 100644 --- a/rust/alloc/str.rs +++ b/rust/alloc/str.rs @@ -370,6 +370,8 @@ impl str { /// assert_eq!(new_year, new_year.to_lowercase()); /// ``` #[cfg(not(no_global_oom_handling))] + #[must_use = "this returns the lowercase string as a new String, \ + without modifying the original"] #[stable(feature = "unicode_case_mapping", since = "1.2.0")] pub fn to_lowercase(&self) -> String { let mut s = String::with_capacity(self.len()); @@ -450,6 +452,8 @@ impl str { /// assert_eq!("TSCHÜSS", s.to_uppercase()); /// ``` #[cfg(not(no_global_oom_handling))] + #[must_use = "this returns the uppercase string as a new String, \ + without modifying the original"] #[stable(feature = "unicode_case_mapping", since = "1.2.0")] pub fn to_uppercase(&self) -> String { let mut s = String::with_capacity(self.len()); @@ -537,6 +541,7 @@ impl str { /// [`make_ascii_uppercase`]: str::make_ascii_uppercase /// [`to_uppercase`]: #method.to_uppercase #[cfg(not(no_global_oom_handling))] + #[must_use = "to uppercase the value in-place, use `make_ascii_uppercase()`"] #[stable(feature = "ascii_methods_on_intrinsics", since = "1.23.0")] #[inline] pub fn to_ascii_uppercase(&self) -> String { @@ -568,6 +573,7 @@ impl str { /// [`make_ascii_lowercase`]: str::make_ascii_lowercase /// [`to_lowercase`]: #method.to_lowercase #[cfg(not(no_global_oom_handling))] + #[must_use = "to lowercase the value in-place, use `make_ascii_lowercase()`"] #[stable(feature = "ascii_methods_on_intrinsics", since = "1.23.0")] #[inline] pub fn to_ascii_lowercase(&self) -> String { @@ -608,6 +614,7 @@ impl str { /// assert_eq!("☺", &*smile); /// ``` #[stable(feature = "str_box_extras", since = "1.20.0")] +#[must_use] #[inline] pub unsafe fn from_boxed_utf8_unchecked(v: Box<[u8]>) -> Box { unsafe { Box::from_raw(Box::into_raw(v) as *mut str) } diff --git a/rust/alloc/string.rs b/rust/alloc/string.rs index fb4d186e4214ba..a5bdf6df00dc86 100644 --- a/rust/alloc/string.rs +++ b/rust/alloc/string.rs @@ -81,7 +81,7 @@ use crate::vec::Vec; /// /// # Examples /// -/// You can create a `String` from [a literal string][`str`] with [`String::from`]: +/// You can create a `String` from [a literal string][`&str`] with [`String::from`]: /// /// [`String::from`]: From::from /// @@ -130,7 +130,7 @@ use crate::vec::Vec; /// println!("The first letter of s is {}", s[0]); // ERROR!!! /// ``` /// -/// [`OsString`]: ../../std/ffi/struct.OsString.html +/// [`OsString`]: ../../std/ffi/struct.OsString.html "ffi::OsString" /// /// Indexing is intended to be a constant-time operation, but UTF-8 encoding /// does not allow us to do this. Furthermore, it's not clear what sort of @@ -143,7 +143,7 @@ use crate::vec::Vec; /// /// # Deref /// -/// `String`s implement [`Deref`]``, and so inherit all of [`str`]'s +/// `String` implements [Deref], and so inherits all of [`str`]'s /// methods. In addition, this means that you can pass a `String` to a /// function which takes a [`&str`] by using an ampersand (`&`): /// @@ -184,7 +184,7 @@ use crate::vec::Vec; /// to explicitly extract the string slice containing the string. The second /// way changes `example_func(&example_string);` to /// `example_func(&*example_string);`. In this case we are dereferencing a -/// `String` to a [`str`][`&str`], then referencing the [`str`][`&str`] back to +/// `String` to a [`str`], then referencing the [`str`] back to /// [`&str`]. The second way is more idiomatic, however both work to do the /// conversion explicitly rather than relying on the implicit conversion. /// @@ -284,12 +284,14 @@ use crate::vec::Vec; /// /// Here, there's no need to allocate more memory inside the loop. /// -/// [`str`]: prim@str -/// [`&str`]: prim@str -/// [`Deref`]: core::ops::Deref +/// [str]: prim@str "str" +/// [`str`]: prim@str "str" +/// [`&str`]: prim@str "&str" +/// [Deref]: core::ops::Deref "ops::Deref" +/// [`Deref`]: core::ops::Deref "ops::Deref" /// [`as_str()`]: String::as_str #[derive(PartialOrd, Eq, Ord)] -#[cfg_attr(not(test), rustc_diagnostic_item = "string_type")] +#[cfg_attr(not(test), rustc_diagnostic_item = "String")] #[stable(feature = "rust1", since = "1.0.0")] pub struct String { vec: Vec, @@ -310,10 +312,10 @@ pub struct String { /// an analogue to `FromUtf8Error`, and you can get one from a `FromUtf8Error` /// through the [`utf8_error`] method. /// -/// [`Utf8Error`]: core::str::Utf8Error -/// [`std::str`]: core::str -/// [`&str`]: prim@str -/// [`utf8_error`]: Self::utf8_error +/// [`Utf8Error`]: str::Utf8Error "std::str::Utf8Error" +/// [`std::str`]: core::str "std::str" +/// [`&str`]: prim@str "&str" +/// [`utf8_error`]: FromUtf8Error::utf8_error /// /// # Examples /// @@ -378,6 +380,7 @@ impl String { #[inline] #[rustc_const_stable(feature = "const_string_new", since = "1.39.0")] #[stable(feature = "rust1", since = "1.0.0")] + #[must_use] pub const fn new() -> String { String { vec: Vec::new() } } @@ -422,6 +425,7 @@ impl String { #[cfg(not(no_global_oom_handling))] #[inline] #[stable(feature = "rust1", since = "1.0.0")] + #[must_use] pub fn with_capacity(capacity: usize) -> String { String { vec: Vec::with_capacity(capacity) } } @@ -489,8 +493,8 @@ impl String { /// with this error. /// /// [`from_utf8_unchecked`]: String::from_utf8_unchecked - /// [`Vec`]: crate::vec::Vec - /// [`&str`]: prim@str + /// [`Vec`]: crate::vec::Vec "Vec" + /// [`&str`]: prim@str "&str" /// [`into_bytes`]: String::into_bytes #[inline] #[stable(feature = "rust1", since = "1.0.0")] @@ -526,7 +530,7 @@ impl String { /// it's already valid UTF-8, we don't need a new allocation. This return /// type allows us to handle both cases. /// - /// [`Cow<'a, str>`]: crate::borrow::Cow + /// [`Cow<'a, str>`]: crate::borrow::Cow "borrow::Cow" /// /// # Examples /// @@ -627,7 +631,7 @@ impl String { /// conversion requires a memory allocation. /// /// [`from_utf8_lossy`]: String::from_utf8_lossy - /// [`Cow<'a, str>`]: crate::borrow::Cow + /// [`Cow<'a, str>`]: crate::borrow::Cow "borrow::Cow" /// [U+FFFD]: core::char::REPLACEMENT_CHARACTER /// /// # Examples @@ -676,6 +680,7 @@ impl String { /// let rebuilt = unsafe { String::from_raw_parts(ptr, len, cap) }; /// assert_eq!(rebuilt, "hello"); /// ``` + #[must_use = "`self` will be dropped if the result is not used"] #[unstable(feature = "vec_into_raw_parts", reason = "new API", issue = "65816")] pub fn into_raw_parts(self) -> (*mut u8, usize, usize) { self.vec.into_raw_parts() @@ -761,6 +766,7 @@ impl String { /// assert_eq!("💖", sparkle_heart); /// ``` #[inline] + #[must_use] #[stable(feature = "rust1", since = "1.0.0")] pub unsafe fn from_utf8_unchecked(bytes: Vec) -> String { String { vec: bytes } @@ -781,6 +787,7 @@ impl String { /// assert_eq!(&[104, 101, 108, 108, 111][..], &bytes[..]); /// ``` #[inline] + #[must_use = "`self` will be dropped if the result is not used"] #[stable(feature = "rust1", since = "1.0.0")] pub fn into_bytes(self) -> Vec { self.vec @@ -798,6 +805,7 @@ impl String { /// assert_eq!("foo", s.as_str()); /// ``` #[inline] + #[must_use] #[stable(feature = "string_as_str", since = "1.7.0")] pub fn as_str(&self) -> &str { self @@ -818,6 +826,7 @@ impl String { /// assert_eq!("FOOBAR", s_mut_str); /// ``` #[inline] + #[must_use] #[stable(feature = "string_as_str", since = "1.7.0")] pub fn as_mut_str(&mut self) -> &mut str { self @@ -1009,7 +1018,6 @@ impl String { /// # Examples /// /// ``` - /// #![feature(try_reserve)] /// use std::collections::TryReserveError; /// /// fn process_data(data: &str) -> Result { @@ -1025,7 +1033,7 @@ impl String { /// } /// # process_data("rust").expect("why is the test harness OOMing on 4 bytes?"); /// ``` - #[unstable(feature = "try_reserve", reason = "new API", issue = "48043")] + #[stable(feature = "try_reserve", since = "1.57.0")] pub fn try_reserve(&mut self, additional: usize) -> Result<(), TryReserveError> { self.vec.try_reserve(additional) } @@ -1049,7 +1057,6 @@ impl String { /// # Examples /// /// ``` - /// #![feature(try_reserve)] /// use std::collections::TryReserveError; /// /// fn process_data(data: &str) -> Result { @@ -1065,7 +1072,7 @@ impl String { /// } /// # process_data("rust").expect("why is the test harness OOMing on 4 bytes?"); /// ``` - #[unstable(feature = "try_reserve", reason = "new API", issue = "48043")] + #[stable(feature = "try_reserve", since = "1.57.0")] pub fn try_reserve_exact(&mut self, additional: usize) -> Result<(), TryReserveError> { self.vec.try_reserve_exact(additional) } @@ -1160,6 +1167,7 @@ impl String { /// assert_eq!(&[104, 101, 108, 108, 111], s.as_bytes()); /// ``` #[inline] + #[must_use] #[stable(feature = "rust1", since = "1.0.0")] pub fn as_bytes(&self) -> &[u8] { &self.vec @@ -1723,11 +1731,11 @@ impl String { unsafe { self.as_mut_vec() }.splice((start, end), replace_with.bytes()); } - /// Converts this `String` into a [`Box`]`<`[`str`]`>`. + /// Converts this `String` into a [Box]<[str]>. /// /// This will drop any excess capacity. /// - /// [`str`]: prim@str + /// [str]: prim@str "str" /// /// # Examples /// @@ -1740,6 +1748,7 @@ impl String { /// ``` #[cfg(not(no_global_oom_handling))] #[stable(feature = "box_str", since = "1.4.0")] + #[must_use = "`self` will be dropped if the result is not used"] #[inline] pub fn into_boxed_str(self) -> Box { let slice = self.vec.into_boxed_slice(); @@ -1762,6 +1771,7 @@ impl FromUtf8Error { /// /// assert_eq!(&[0, 159], value.unwrap_err().as_bytes()); /// ``` + #[must_use] #[stable(feature = "from_utf8_error_as_bytes", since = "1.26.0")] pub fn as_bytes(&self) -> &[u8] { &self.bytes[..] @@ -1785,6 +1795,7 @@ impl FromUtf8Error { /// /// assert_eq!(vec![0, 159], value.unwrap_err().into_bytes()); /// ``` + #[must_use = "`self` will be dropped if the result is not used"] #[stable(feature = "rust1", since = "1.0.0")] pub fn into_bytes(self) -> Vec { self.bytes @@ -1797,8 +1808,8 @@ impl FromUtf8Error { /// an analogue to `FromUtf8Error`. See its documentation for more details /// on using it. /// - /// [`std::str`]: core::str - /// [`&str`]: prim@str + /// [`std::str`]: core::str "std::str" + /// [`&str`]: prim@str "&str" /// /// # Examples /// @@ -2321,7 +2332,7 @@ impl ops::DerefMut for String { /// /// This alias exists for backwards compatibility, and may be eventually deprecated. /// -/// [`Infallible`]: core::convert::Infallible +/// [`Infallible`]: core::convert::Infallible "convert::Infallible" #[stable(feature = "str_parse_error", since = "1.5.0")] pub type ParseError = core::convert::Infallible; @@ -2608,7 +2619,7 @@ impl<'a> From<&'a str> for Cow<'a, str> { /// assert_eq!(Cow::from("eggplant"), Cow::Borrowed("eggplant")); /// ``` /// - /// [`Borrowed`]: crate::borrow::Cow::Borrowed + /// [`Borrowed`]: crate::borrow::Cow::Borrowed "borrow::Cow::Borrowed" #[inline] fn from(s: &'a str) -> Cow<'a, str> { Cow::Borrowed(s) @@ -2631,7 +2642,7 @@ impl<'a> From for Cow<'a, str> { /// assert_eq!(Cow::from(s), Cow::<'static, str>::Owned(s2)); /// ``` /// - /// [`Owned`]: crate::borrow::Cow::Owned + /// [`Owned`]: crate::borrow::Cow::Owned "borrow::Cow::Owned" #[inline] fn from(s: String) -> Cow<'a, str> { Cow::Owned(s) @@ -2653,7 +2664,7 @@ impl<'a> From<&'a String> for Cow<'a, str> { /// assert_eq!(Cow::from(&s), Cow::Borrowed("eggplant")); /// ``` /// - /// [`Borrowed`]: crate::borrow::Cow::Borrowed + /// [`Borrowed`]: crate::borrow::Cow::Borrowed "borrow::Cow::Borrowed" #[inline] fn from(s: &'a String) -> Cow<'a, str> { Cow::Borrowed(s.as_str()) @@ -2777,6 +2788,7 @@ impl<'a> Drain<'a> { /// let _ = drain.next().unwrap(); /// assert_eq!(drain.as_str(), "bc"); /// ``` + #[must_use] #[stable(feature = "string_drain_as_str", since = "1.55.0")] pub fn as_str(&self) -> &str { self.iter.as_str() diff --git a/rust/alloc/vec/drain.rs b/rust/alloc/vec/drain.rs index 65f7e32e95fd75..43efc57a7a8d4f 100644 --- a/rust/alloc/vec/drain.rs +++ b/rust/alloc/vec/drain.rs @@ -54,6 +54,7 @@ impl<'a, T, A: Allocator> Drain<'a, T, A> { /// let _ = drain.next().unwrap(); /// assert_eq!(drain.as_slice(), &['b', 'c']); /// ``` + #[must_use] #[stable(feature = "vec_drain_as_slice", since = "1.46.0")] pub fn as_slice(&self) -> &[T] { self.iter.as_slice() diff --git a/rust/alloc/vec/into_iter.rs b/rust/alloc/vec/into_iter.rs index 81c3f2e7b387ed..7acd7fb5a09d4d 100644 --- a/rust/alloc/vec/into_iter.rs +++ b/rust/alloc/vec/into_iter.rs @@ -163,6 +163,29 @@ impl Iterator for IntoIter { (exact, Some(exact)) } + #[inline] + fn advance_by(&mut self, n: usize) -> Result<(), usize> { + let step_size = self.len().min(n); + let to_drop = ptr::slice_from_raw_parts_mut(self.ptr as *mut T, step_size); + if mem::size_of::() == 0 { + // SAFETY: due to unchecked casts of unsigned amounts to signed offsets the wraparound + // effectively results in unsigned pointers representing positions 0..usize::MAX, + // which is valid for ZSTs. + self.ptr = unsafe { arith_offset(self.ptr as *const i8, step_size as isize) as *mut T } + } else { + // SAFETY: the min() above ensures that step_size is in bounds + self.ptr = unsafe { self.ptr.add(step_size) }; + } + // SAFETY: the min() above ensures that step_size is in bounds + unsafe { + ptr::drop_in_place(to_drop); + } + if step_size < n { + return Err(step_size); + } + Ok(()) + } + #[inline] fn count(self) -> usize { self.len() @@ -205,6 +228,29 @@ impl DoubleEndedIterator for IntoIter { Some(unsafe { ptr::read(self.end) }) } } + + #[inline] + fn advance_back_by(&mut self, n: usize) -> Result<(), usize> { + let step_size = self.len().min(n); + if mem::size_of::() == 0 { + // SAFETY: same as for advance_by() + self.end = unsafe { + arith_offset(self.end as *const i8, step_size.wrapping_neg() as isize) as *mut T + } + } else { + // SAFETY: same as for advance_by() + self.end = unsafe { self.end.offset(step_size.wrapping_neg() as isize) }; + } + let to_drop = ptr::slice_from_raw_parts_mut(self.end as *mut T, step_size); + // SAFETY: same as for advance_by() + unsafe { + ptr::drop_in_place(to_drop); + } + if step_size < n { + return Err(step_size); + } + Ok(()) + } } #[stable(feature = "rust1", since = "1.0.0")] @@ -222,14 +268,21 @@ unsafe impl TrustedLen for IntoIter {} #[doc(hidden)] #[unstable(issue = "none", feature = "std_internals")] +#[rustc_unsafe_specialization_marker] +pub trait NonDrop {} + // T: Copy as approximation for !Drop since get_unchecked does not advance self.ptr // and thus we can't implement drop-handling -// +#[unstable(issue = "none", feature = "std_internals")] +impl NonDrop for T {} + +#[doc(hidden)] +#[unstable(issue = "none", feature = "std_internals")] // TrustedRandomAccess (without NoCoerce) must not be implemented because -// subtypes/supertypes of `T` might not be `Copy` +// subtypes/supertypes of `T` might not be `NonDrop` unsafe impl TrustedRandomAccessNoCoerce for IntoIter where - T: Copy, + T: NonDrop, { const MAY_HAVE_SIDE_EFFECT: bool = false; } diff --git a/rust/alloc/vec/mod.rs b/rust/alloc/vec/mod.rs index 6576a058af34d9..5e0cf38ad1b4d5 100644 --- a/rust/alloc/vec/mod.rs +++ b/rust/alloc/vec/mod.rs @@ -3,8 +3,8 @@ //! A contiguous growable array type with heap-allocated contents, written //! `Vec`. //! -//! Vectors have `O(1)` indexing, amortized `O(1)` push (to the end) and -//! `O(1)` pop (from the end). +//! Vectors have *O*(1) indexing, amortized *O*(1) push (to the end) and +//! *O*(1) pop (from the end). //! //! Vectors ensure they never allocate more than `isize::MAX` bytes. //! @@ -297,8 +297,8 @@ mod spec_extend; /// on an empty Vec, it will not allocate memory. Similarly, if you store zero-sized /// types inside a `Vec`, it will not allocate space for them. *Note that in this case /// the `Vec` might not report a [`capacity`] of 0*. `Vec` will allocate if and only -/// if [`mem::size_of::`]`() * capacity() > 0`. In general, `Vec`'s allocation -/// details are very subtle — if you intend to allocate memory using a `Vec` +/// if [mem::size_of::\]\() * [capacity]\() > 0. In general, `Vec`'s allocation +/// details are very subtle --- if you intend to allocate memory using a `Vec` /// and use it for something else (either to pass to unsafe code, or to build your /// own memory-backed collection), be sure to deallocate this memory by using /// `from_raw_parts` to recover the `Vec` and then dropping it. @@ -306,8 +306,8 @@ mod spec_extend; /// If a `Vec` *has* allocated memory, then the memory it points to is on the heap /// (as defined by the allocator Rust is configured to use by default), and its /// pointer points to [`len`] initialized, contiguous elements in order (what -/// you would see if you coerced it to a slice), followed by [`capacity`]` - -/// `[`len`] logically uninitialized, contiguous elements. +/// you would see if you coerced it to a slice), followed by [capacity] - [len] +/// logically uninitialized, contiguous elements. /// /// A vector containing the elements `'a'` and `'b'` with capacity 4 can be /// visualized as below. The top part is the `Vec` struct, it contains a @@ -349,7 +349,7 @@ mod spec_extend; /// /// [`push`] and [`insert`] will never (re)allocate if the reported capacity is /// sufficient. [`push`] and [`insert`] *will* (re)allocate if -/// [`len`]` == `[`capacity`]. That is, the reported capacity is completely +/// [len] == [capacity]. That is, the reported capacity is completely /// accurate, and can be relied on. It can even be used to manually free the memory /// allocated by a `Vec` if desired. Bulk insertion methods *may* reallocate, even /// when not necessary. @@ -361,7 +361,7 @@ mod spec_extend; /// /// `vec![x; n]`, `vec![a, b, c, d]`, and /// [`Vec::with_capacity(n)`][`Vec::with_capacity`], will all produce a `Vec` -/// with exactly the requested capacity. If [`len`]` == `[`capacity`], +/// with exactly the requested capacity. If [len] == [capacity], /// (as is the case for the [`vec!`] macro), then a `Vec` can be converted to /// and from a [`Box<[T]>`][owned slice] without reallocating or moving the elements. /// @@ -370,7 +370,7 @@ mod spec_extend; /// scratch space that it may use however it wants. It will generally just do /// whatever is most efficient or otherwise easy to implement. Do not rely on /// removed data to be erased for security purposes. Even if you drop a `Vec`, its -/// buffer may simply be reused by another `Vec`. Even if you zero a `Vec`'s memory +/// buffer may simply be reused by another allocation. Even if you zero a `Vec`'s memory /// first, that might not actually happen because the optimizer does not consider /// this a side-effect that must be preserved. There is one case which we will /// not break, however: using `unsafe` code to write to the excess capacity, @@ -385,8 +385,10 @@ mod spec_extend; /// [`&str`]: type@str /// [`shrink_to_fit`]: Vec::shrink_to_fit /// [`shrink_to`]: Vec::shrink_to +/// [capacity]: Vec::capacity /// [`capacity`]: Vec::capacity -/// [`mem::size_of::`]: core::mem::size_of +/// [mem::size_of::\]: core::mem::size_of +/// [len]: Vec::len /// [`len`]: Vec::len /// [`push`]: Vec::push /// [`insert`]: Vec::insert @@ -394,7 +396,7 @@ mod spec_extend; /// [`MaybeUninit`]: core::mem::MaybeUninit /// [owned slice]: Box #[stable(feature = "rust1", since = "1.0.0")] -#[cfg_attr(not(test), rustc_diagnostic_item = "vec_type")] +#[cfg_attr(not(test), rustc_diagnostic_item = "Vec")] #[rustc_insignificant_dtor] pub struct Vec { buf: RawVec, @@ -419,6 +421,7 @@ impl Vec { #[inline] #[rustc_const_stable(feature = "const_vec_new", since = "1.39.0")] #[stable(feature = "rust1", since = "1.0.0")] + #[must_use] pub const fn new() -> Self { Vec { buf: RawVec::NEW, len: 0 } } @@ -463,6 +466,7 @@ impl Vec { #[cfg(not(no_global_oom_handling))] #[inline] #[stable(feature = "rust1", since = "1.0.0")] + #[must_use] pub fn with_capacity(capacity: usize) -> Self { Self::with_capacity_in(capacity, Global) } @@ -938,7 +942,6 @@ impl Vec { /// # Examples /// /// ``` - /// #![feature(try_reserve)] /// use std::collections::TryReserveError; /// /// fn process_data(data: &[u32]) -> Result, TryReserveError> { @@ -956,7 +959,7 @@ impl Vec { /// } /// # process_data(&[1, 2, 3]).expect("why is the test harness OOMing on 12 bytes?"); /// ``` - #[unstable(feature = "try_reserve", reason = "new API", issue = "48043")] + #[stable(feature = "try_reserve", since = "1.57.0")] pub fn try_reserve(&mut self, additional: usize) -> Result<(), TryReserveError> { self.buf.try_reserve(self.len, additional) } @@ -981,7 +984,6 @@ impl Vec { /// # Examples /// /// ``` - /// #![feature(try_reserve)] /// use std::collections::TryReserveError; /// /// fn process_data(data: &[u32]) -> Result, TryReserveError> { @@ -999,7 +1001,7 @@ impl Vec { /// } /// # process_data(&[1, 2, 3]).expect("why is the test harness OOMing on 12 bytes?"); /// ``` - #[unstable(feature = "try_reserve", reason = "new API", issue = "48043")] + #[stable(feature = "try_reserve", since = "1.57.0")] pub fn try_reserve_exact(&mut self, additional: usize) -> Result<(), TryReserveError> { self.buf.try_reserve_exact(self.len, additional) } @@ -1422,7 +1424,7 @@ impl Vec { /// /// The removed element is replaced by the last element of the vector. /// - /// This does not preserve ordering, but is O(1). + /// This does not preserve ordering, but is *O*(1). /// /// # Panics /// @@ -1639,7 +1641,15 @@ impl Vec { let mut g = BackshiftOnDrop { v: self, processed_len: 0, deleted_cnt: 0, original_len }; - while g.processed_len < original_len { + // process_one return a bool indicates whether the processing element should be retained. + #[inline(always)] + fn process_one( + f: &mut F, + g: &mut BackshiftOnDrop<'_, T, A>, + ) -> bool + where + F: FnMut(&T) -> bool, + { // SAFETY: Unchecked element must be valid. let cur = unsafe { &mut *g.v.as_mut_ptr().add(g.processed_len) }; if !f(cur) { @@ -1649,9 +1659,9 @@ impl Vec { // SAFETY: We never touch this element again after dropped. unsafe { ptr::drop_in_place(cur) }; // We already advanced the counter. - continue; + return false; } - if g.deleted_cnt > 0 { + if DELETED { // SAFETY: `deleted_cnt` > 0, so the hole slot must not overlap with current element. // We use copy for move, and never touch this element again. unsafe { @@ -1660,6 +1670,19 @@ impl Vec { } } g.processed_len += 1; + return true; + } + + // Stage 1: Nothing was deleted. + while g.processed_len != original_len { + if !process_one::(&mut f, &mut g) { + break; + } + } + + // Stage 2: Some elements were deleted. + while g.processed_len != original_len { + process_one::(&mut f, &mut g); } // All item are processed. This can be optimized to `set_len` by LLVM. @@ -2137,8 +2160,9 @@ impl Vec { /// `'a`. If the type has only static references, or none at all, then this /// may be chosen to be `'static`. /// - /// This function is similar to the [`leak`][Box::leak] function on [`Box`] - /// except that there is no way to recover the leaked memory. + /// As of Rust 1.57, this method does not reallocate or shrink the `Vec`, + /// so the leaked allocation may include unused capacity that is not part + /// of the returned slice. /// /// This function is mainly useful for data that lives for the remainder of /// the program's life. Dropping the returned reference will cause a memory @@ -2161,7 +2185,8 @@ impl Vec { where A: 'a, { - Box::leak(self.into_boxed_slice()) + let mut me = ManuallyDrop::new(self); + unsafe { slice::from_raw_parts_mut(me.as_mut_ptr(), me.len) } } /// Returns the remaining spare capacity of the vector as a slice of @@ -2301,6 +2326,7 @@ impl Vec { /// in order to be able to clone the passed value. /// If you need more flexibility (or want to rely on [`Default`] instead of /// [`Clone`]), use [`Vec::resize_with`]. + /// If you only need to resize to a smaller size, use [`Vec::truncate`]. /// /// # Examples /// @@ -2414,7 +2440,12 @@ impl Vec { /// Copies elements from `src` range to the end of the vector. /// - /// ## Examples + /// # Panics + /// + /// Panics if the starting point is greater than the end point or if + /// the end point is greater than the length of the vector. + /// + /// # Examples /// /// ``` /// let mut vec = vec![0, 1, 2, 3, 4]; @@ -2519,7 +2550,7 @@ impl Vec { unsafe { let mut ptr = self.as_mut_ptr().add(self.len()); // Use SetLenOnDrop to work around bug where compiler - // may not realize the store through `ptr` through self.set_len() + // might not realize the store through `ptr` through self.set_len() // don't alias. let mut local_len = SetLenOnDrop::new(&mut self.len); @@ -3147,6 +3178,7 @@ impl From<&mut [T]> for Vec { } } +#[cfg(not(no_global_oom_handling))] #[stable(feature = "vec_from_array", since = "1.44.0")] impl From<[T; N]> for Vec { #[cfg(not(test))]