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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-17 12:20:39 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-17 12:20:39 +0000 |
commit | 1376c5a617be5c25655d0d7cb63e3beaa5a6e026 (patch) | |
tree | 3bb8d61aee02bc7a15eab3f36e3b921afc2075d0 /library/core/src/slice | |
parent | Releasing progress-linux version 1.69.0+dfsg1-1~progress7.99u1. (diff) | |
download | rustc-1376c5a617be5c25655d0d7cb63e3beaa5a6e026.tar.xz rustc-1376c5a617be5c25655d0d7cb63e3beaa5a6e026.zip |
Merging upstream version 1.70.0+dfsg1.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'library/core/src/slice')
-rw-r--r-- | library/core/src/slice/index.rs | 14 | ||||
-rw-r--r-- | library/core/src/slice/iter.rs | 4 | ||||
-rw-r--r-- | library/core/src/slice/iter/macros.rs | 22 | ||||
-rw-r--r-- | library/core/src/slice/mod.rs | 30 | ||||
-rw-r--r-- | library/core/src/slice/sort.rs | 2 |
5 files changed, 46 insertions, 26 deletions
diff --git a/library/core/src/slice/index.rs b/library/core/src/slice/index.rs index c295a0e06..353935324 100644 --- a/library/core/src/slice/index.rs +++ b/library/core/src/slice/index.rs @@ -2,6 +2,7 @@ use crate::intrinsics::assert_unsafe_precondition; use crate::intrinsics::const_eval_select; +use crate::intrinsics::unchecked_sub; use crate::ops; use crate::ptr; @@ -371,25 +372,25 @@ unsafe impl<T> const SliceIndex<[T]> for ops::Range<usize> { #[inline] unsafe fn get_unchecked(self, slice: *const [T]) -> *const [T] { - let this = ops::Range { start: self.start, end: self.end }; + let this = ops::Range { ..self }; // SAFETY: the caller guarantees that `slice` is not dangling, so it // cannot be longer than `isize::MAX`. They also guarantee that // `self` is in bounds of `slice` so `self` cannot overflow an `isize`, - // so the call to `add` is safe. - + // so the call to `add` is safe and the length calculation cannot overflow. unsafe { assert_unsafe_precondition!( "slice::get_unchecked requires that the range is within the slice", [T](this: ops::Range<usize>, slice: *const [T]) => this.end >= this.start && this.end <= slice.len() ); - ptr::slice_from_raw_parts(slice.as_ptr().add(self.start), self.end - self.start) + let new_len = unchecked_sub(self.end, self.start); + ptr::slice_from_raw_parts(slice.as_ptr().add(self.start), new_len) } } #[inline] unsafe fn get_unchecked_mut(self, slice: *mut [T]) -> *mut [T] { - let this = ops::Range { start: self.start, end: self.end }; + let this = ops::Range { ..self }; // SAFETY: see comments for `get_unchecked` above. unsafe { assert_unsafe_precondition!( @@ -397,7 +398,8 @@ unsafe impl<T> const SliceIndex<[T]> for ops::Range<usize> { [T](this: ops::Range<usize>, slice: *mut [T]) => this.end >= this.start && this.end <= slice.len() ); - ptr::slice_from_raw_parts_mut(slice.as_mut_ptr().add(self.start), self.end - self.start) + let new_len = unchecked_sub(self.end, self.start); + ptr::slice_from_raw_parts_mut(slice.as_mut_ptr().add(self.start), new_len) } } diff --git a/library/core/src/slice/iter.rs b/library/core/src/slice/iter.rs index c4317799b..88b84bd13 100644 --- a/library/core/src/slice/iter.rs +++ b/library/core/src/slice/iter.rs @@ -132,9 +132,7 @@ iterator! {struct Iter -> *const T, &'a T, const, {/* no mut */}, { Self: Sized, F: FnMut(&Self::Item, &Self::Item) -> Option<Ordering>, { - self.as_slice().windows(2).all(|w| { - compare(&&w[0], &&w[1]).map(|o| o != Ordering::Greater).unwrap_or(false) - }) + self.as_slice().is_sorted_by(|a, b| compare(&a, &b)) } }} diff --git a/library/core/src/slice/iter/macros.rs b/library/core/src/slice/iter/macros.rs index 89b92a7d5..392752f2a 100644 --- a/library/core/src/slice/iter/macros.rs +++ b/library/core/src/slice/iter/macros.rs @@ -176,11 +176,11 @@ macro_rules! iterator { } #[inline] - fn advance_by(&mut self, n: usize) -> Result<(), usize> { + fn advance_by(&mut self, n: usize) -> Result<(), NonZeroUsize> { let advance = cmp::min(len!(self), n); // SAFETY: By construction, `advance` does not exceed `self.len()`. unsafe { self.post_inc_start(advance) }; - if advance == n { Ok(()) } else { Err(advance) } + NonZeroUsize::new(n - advance).map_or(Ok(()), Err) } #[inline] @@ -371,11 +371,11 @@ macro_rules! iterator { } #[inline] - fn advance_back_by(&mut self, n: usize) -> Result<(), usize> { + fn advance_back_by(&mut self, n: usize) -> Result<(), NonZeroUsize> { let advance = cmp::min(len!(self), n); // SAFETY: By construction, `advance` does not exceed `self.len()`. unsafe { self.pre_dec_end(advance) }; - if advance == n { Ok(()) } else { Err(advance) } + NonZeroUsize::new(n - advance).map_or(Ok(()), Err) } } @@ -393,6 +393,20 @@ macro_rules! iterator { } } } + + #[stable(feature = "default_iters", since = "1.70.0")] + impl<T> Default for $name<'_, T> { + /// Creates an empty slice iterator. + /// + /// ``` + #[doc = concat!("# use core::slice::", stringify!($name), ";")] + #[doc = concat!("let iter: ", stringify!($name<'_, u8>), " = Default::default();")] + /// assert_eq!(iter.len(), 0); + /// ``` + fn default() -> Self { + (& $( $mut_ )? []).into_iter() + } + } } } diff --git a/library/core/src/slice/mod.rs b/library/core/src/slice/mod.rs index 1cd86b445..f541808a6 100644 --- a/library/core/src/slice/mod.rs +++ b/library/core/src/slice/mod.rs @@ -1695,7 +1695,13 @@ impl<T> [T] { let ptr = self.as_ptr(); // SAFETY: Caller has to check that `0 <= mid <= self.len()` - unsafe { (from_raw_parts(ptr, mid), from_raw_parts(ptr.add(mid), len - mid)) } + unsafe { + assert_unsafe_precondition!( + "slice::split_at_unchecked requires the index to be within the slice", + (mid: usize, len: usize) => mid <= len + ); + (from_raw_parts(ptr, mid), from_raw_parts(ptr.add(mid), len - mid)) + } } /// Divides one mutable slice into two at an index, without doing bounds checking. @@ -2381,7 +2387,8 @@ impl<T> [T] { } /// Binary searches this slice for a given element. - /// This behaves similarly to [`contains`] if this slice is sorted. + /// If the slice is not sorted, the returned result is unspecified and + /// meaningless. /// /// If the value is found then [`Result::Ok`] is returned, containing the /// index of the matching element. If there are multiple matches, then any @@ -2393,7 +2400,6 @@ impl<T> [T] { /// /// See also [`binary_search_by`], [`binary_search_by_key`], and [`partition_point`]. /// - /// [`contains`]: slice::contains /// [`binary_search_by`]: slice::binary_search_by /// [`binary_search_by_key`]: slice::binary_search_by_key /// [`partition_point`]: slice::partition_point @@ -2456,12 +2462,13 @@ impl<T> [T] { } /// Binary searches this slice with a comparator function. - /// This behaves similarly to [`contains`] if this slice is sorted. /// - /// The comparator function should implement an order consistent - /// with the sort order of the underlying slice, returning an - /// order code that indicates whether its argument is `Less`, - /// `Equal` or `Greater` the desired target. + /// The comparator function should return an order code that indicates + /// whether its argument is `Less`, `Equal` or `Greater` the desired + /// target. + /// If the slice is not sorted or if the comparator function does not + /// implement an order consistent with the sort order of the underlying + /// slice, the returned result is unspecified and meaningless. /// /// If the value is found then [`Result::Ok`] is returned, containing the /// index of the matching element. If there are multiple matches, then any @@ -2473,7 +2480,6 @@ impl<T> [T] { /// /// See also [`binary_search`], [`binary_search_by_key`], and [`partition_point`]. /// - /// [`contains`]: slice::contains /// [`binary_search`]: slice::binary_search /// [`binary_search_by_key`]: slice::binary_search_by_key /// [`partition_point`]: slice::partition_point @@ -2542,10 +2548,11 @@ impl<T> [T] { } /// Binary searches this slice with a key extraction function. - /// This behaves similarly to [`contains`] if this slice is sorted. /// /// Assumes that the slice is sorted by the key, for instance with /// [`sort_by_key`] using the same key extraction function. + /// If the slice is not sorted by the key, the returned result is + /// unspecified and meaningless. /// /// If the value is found then [`Result::Ok`] is returned, containing the /// index of the matching element. If there are multiple matches, then any @@ -2557,7 +2564,6 @@ impl<T> [T] { /// /// See also [`binary_search`], [`binary_search_by`], and [`partition_point`]. /// - /// [`contains`]: slice::contains /// [`sort_by_key`]: slice::sort_by_key /// [`binary_search`]: slice::binary_search /// [`binary_search_by`]: slice::binary_search_by @@ -3816,7 +3822,7 @@ impl<T> [T] { where F: FnMut(&'a T, &'a T) -> Option<Ordering>, { - self.iter().is_sorted_by(|a, b| compare(*a, *b)) + self.array_windows().all(|[a, b]| compare(a, b).map_or(false, Ordering::is_le)) } /// Checks if the elements of this slice are sorted using the given key extraction function. diff --git a/library/core/src/slice/sort.rs b/library/core/src/slice/sort.rs index 2333f60a8..07fd96f92 100644 --- a/library/core/src/slice/sort.rs +++ b/library/core/src/slice/sort.rs @@ -1486,7 +1486,7 @@ where } /// Finds a streak of presorted elements starting at the beginning of the slice. Returns the first -/// value that is not part of said streak, and a bool denoting wether the streak was reversed. +/// value that is not part of said streak, and a bool denoting whether the streak was reversed. /// Streaks can be increasing or decreasing. fn find_streak<T, F>(v: &[T], is_less: &mut F) -> (usize, bool) where |