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-rw-r--r--vendor/indexmap/src/set/slice.rs278
1 files changed, 278 insertions, 0 deletions
diff --git a/vendor/indexmap/src/set/slice.rs b/vendor/indexmap/src/set/slice.rs
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+++ b/vendor/indexmap/src/set/slice.rs
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+use super::{Bucket, Entries, IndexSet, IntoIter, Iter};
+use crate::util::try_simplify_range;
+
+use alloc::boxed::Box;
+use alloc::vec::Vec;
+use core::cmp::Ordering;
+use core::fmt;
+use core::hash::{Hash, Hasher};
+use core::ops::{self, Bound, Index, RangeBounds};
+
+/// A dynamically-sized slice of values in an `IndexSet`.
+///
+/// This supports indexed operations much like a `[T]` slice,
+/// but not any hashed operations on the values.
+///
+/// Unlike `IndexSet`, `Slice` does consider the order for `PartialEq`
+/// and `Eq`, and it also implements `PartialOrd`, `Ord`, and `Hash`.
+#[repr(transparent)]
+pub struct Slice<T> {
+ pub(crate) entries: [Bucket<T>],
+}
+
+// SAFETY: `Slice<T>` is a transparent wrapper around `[Bucket<T>]`,
+// and reference lifetimes are bound together in function signatures.
+#[allow(unsafe_code)]
+impl<T> Slice<T> {
+ pub(super) fn from_slice(entries: &[Bucket<T>]) -> &Self {
+ unsafe { &*(entries as *const [Bucket<T>] as *const Self) }
+ }
+
+ pub(super) fn from_boxed(entries: Box<[Bucket<T>]>) -> Box<Self> {
+ unsafe { Box::from_raw(Box::into_raw(entries) as *mut Self) }
+ }
+
+ fn into_boxed(self: Box<Self>) -> Box<[Bucket<T>]> {
+ unsafe { Box::from_raw(Box::into_raw(self) as *mut [Bucket<T>]) }
+ }
+}
+
+impl<T> Slice<T> {
+ pub(crate) fn into_entries(self: Box<Self>) -> Vec<Bucket<T>> {
+ self.into_boxed().into_vec()
+ }
+
+ /// Return the number of elements in the set slice.
+ pub fn len(&self) -> usize {
+ self.entries.len()
+ }
+
+ /// Returns true if the set slice contains no elements.
+ pub fn is_empty(&self) -> bool {
+ self.entries.is_empty()
+ }
+
+ /// Get a value by index.
+ ///
+ /// Valid indices are *0 <= index < self.len()*
+ pub fn get_index(&self, index: usize) -> Option<&T> {
+ self.entries.get(index).map(Bucket::key_ref)
+ }
+
+ /// Returns a slice of values in the given range of indices.
+ ///
+ /// Valid indices are *0 <= index < self.len()*
+ pub fn get_range<R: RangeBounds<usize>>(&self, range: R) -> Option<&Self> {
+ let range = try_simplify_range(range, self.entries.len())?;
+ self.entries.get(range).map(Self::from_slice)
+ }
+
+ /// Get the first value.
+ pub fn first(&self) -> Option<&T> {
+ self.entries.first().map(Bucket::key_ref)
+ }
+
+ /// Get the last value.
+ pub fn last(&self) -> Option<&T> {
+ self.entries.last().map(Bucket::key_ref)
+ }
+
+ /// Divides one slice into two at an index.
+ ///
+ /// ***Panics*** if `index > len`.
+ pub fn split_at(&self, index: usize) -> (&Self, &Self) {
+ let (first, second) = self.entries.split_at(index);
+ (Self::from_slice(first), Self::from_slice(second))
+ }
+
+ /// Returns the first value and the rest of the slice,
+ /// or `None` if it is empty.
+ pub fn split_first(&self) -> Option<(&T, &Self)> {
+ if let [first, rest @ ..] = &self.entries {
+ Some((&first.key, Self::from_slice(rest)))
+ } else {
+ None
+ }
+ }
+
+ /// Returns the last value and the rest of the slice,
+ /// or `None` if it is empty.
+ pub fn split_last(&self) -> Option<(&T, &Self)> {
+ if let [rest @ .., last] = &self.entries {
+ Some((&last.key, Self::from_slice(rest)))
+ } else {
+ None
+ }
+ }
+
+ /// Return an iterator over the values of the set slice.
+ pub fn iter(&self) -> Iter<'_, T> {
+ Iter::new(&self.entries)
+ }
+}
+
+impl<'a, T> IntoIterator for &'a Slice<T> {
+ type IntoIter = Iter<'a, T>;
+ type Item = &'a T;
+
+ fn into_iter(self) -> Self::IntoIter {
+ self.iter()
+ }
+}
+
+impl<T> IntoIterator for Box<Slice<T>> {
+ type IntoIter = IntoIter<T>;
+ type Item = T;
+
+ fn into_iter(self) -> Self::IntoIter {
+ IntoIter::new(self.into_entries())
+ }
+}
+
+impl<T> Default for &'_ Slice<T> {
+ fn default() -> Self {
+ Slice::from_slice(&[])
+ }
+}
+
+impl<T> Default for Box<Slice<T>> {
+ fn default() -> Self {
+ Slice::from_boxed(Box::default())
+ }
+}
+
+impl<T: Clone> Clone for Box<Slice<T>> {
+ fn clone(&self) -> Self {
+ Slice::from_boxed(self.entries.to_vec().into_boxed_slice())
+ }
+}
+
+impl<T: Copy> From<&Slice<T>> for Box<Slice<T>> {
+ fn from(slice: &Slice<T>) -> Self {
+ Slice::from_boxed(Box::from(&slice.entries))
+ }
+}
+
+impl<T: fmt::Debug> fmt::Debug for Slice<T> {
+ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+ f.debug_list().entries(self).finish()
+ }
+}
+
+impl<T: PartialEq> PartialEq for Slice<T> {
+ fn eq(&self, other: &Self) -> bool {
+ self.len() == other.len() && self.iter().eq(other)
+ }
+}
+
+impl<T: Eq> Eq for Slice<T> {}
+
+impl<T: PartialOrd> PartialOrd for Slice<T> {
+ fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+ self.iter().partial_cmp(other)
+ }
+}
+
+impl<T: Ord> Ord for Slice<T> {
+ fn cmp(&self, other: &Self) -> Ordering {
+ self.iter().cmp(other)
+ }
+}
+
+impl<T: Hash> Hash for Slice<T> {
+ fn hash<H: Hasher>(&self, state: &mut H) {
+ self.len().hash(state);
+ for value in self {
+ value.hash(state);
+ }
+ }
+}
+
+impl<T> Index<usize> for Slice<T> {
+ type Output = T;
+
+ fn index(&self, index: usize) -> &Self::Output {
+ &self.entries[index].key
+ }
+}
+
+// We can't have `impl<I: RangeBounds<usize>> Index<I>` because that conflicts with `Index<usize>`.
+// Instead, we repeat the implementations for all the core range types.
+macro_rules! impl_index {
+ ($($range:ty),*) => {$(
+ impl<T, S> Index<$range> for IndexSet<T, S> {
+ type Output = Slice<T>;
+
+ fn index(&self, range: $range) -> &Self::Output {
+ Slice::from_slice(&self.as_entries()[range])
+ }
+ }
+
+ impl<T> Index<$range> for Slice<T> {
+ type Output = Self;
+
+ fn index(&self, range: $range) -> &Self::Output {
+ Slice::from_slice(&self.entries[range])
+ }
+ }
+ )*}
+}
+impl_index!(
+ ops::Range<usize>,
+ ops::RangeFrom<usize>,
+ ops::RangeFull,
+ ops::RangeInclusive<usize>,
+ ops::RangeTo<usize>,
+ ops::RangeToInclusive<usize>,
+ (Bound<usize>, Bound<usize>)
+);
+
+#[cfg(test)]
+mod tests {
+ use super::*;
+ use alloc::vec::Vec;
+
+ #[test]
+ fn slice_index() {
+ fn check(vec_slice: &[i32], set_slice: &Slice<i32>, sub_slice: &Slice<i32>) {
+ assert_eq!(set_slice as *const _, sub_slice as *const _);
+ itertools::assert_equal(vec_slice, set_slice);
+ }
+
+ let vec: Vec<i32> = (0..10).map(|i| i * i).collect();
+ let set: IndexSet<i32> = vec.iter().cloned().collect();
+ let slice = set.as_slice();
+
+ // RangeFull
+ check(&vec[..], &set[..], &slice[..]);
+
+ for i in 0usize..10 {
+ // Index
+ assert_eq!(vec[i], set[i]);
+ assert_eq!(vec[i], slice[i]);
+
+ // RangeFrom
+ check(&vec[i..], &set[i..], &slice[i..]);
+
+ // RangeTo
+ check(&vec[..i], &set[..i], &slice[..i]);
+
+ // RangeToInclusive
+ check(&vec[..=i], &set[..=i], &slice[..=i]);
+
+ // (Bound<usize>, Bound<usize>)
+ let bounds = (Bound::Excluded(i), Bound::Unbounded);
+ check(&vec[i + 1..], &set[bounds], &slice[bounds]);
+
+ for j in i..=10 {
+ // Range
+ check(&vec[i..j], &set[i..j], &slice[i..j]);
+ }
+
+ for j in i..10 {
+ // RangeInclusive
+ check(&vec[i..=j], &set[i..=j], &slice[i..=j]);
+ }
+ }
+ }
+}