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-rw-r--r--third_party/rust/indexmap/src/map/slice.rs539
1 files changed, 539 insertions, 0 deletions
diff --git a/third_party/rust/indexmap/src/map/slice.rs b/third_party/rust/indexmap/src/map/slice.rs
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+++ b/third_party/rust/indexmap/src/map/slice.rs
@@ -0,0 +1,539 @@
+use super::{
+ Bucket, Entries, IndexMap, IntoIter, IntoKeys, IntoValues, Iter, IterMut, Keys, Values,
+ ValuesMut,
+};
+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, IndexMut, RangeBounds};
+
+/// A dynamically-sized slice of key-value pairs in an [`IndexMap`].
+///
+/// This supports indexed operations much like a `[(K, V)]` slice,
+/// but not any hashed operations on the map keys.
+///
+/// Unlike `IndexMap`, `Slice` does consider the order for [`PartialEq`]
+/// and [`Eq`], and it also implements [`PartialOrd`], [`Ord`], and [`Hash`].
+#[repr(transparent)]
+pub struct Slice<K, V> {
+ pub(crate) entries: [Bucket<K, V>],
+}
+
+// SAFETY: `Slice<K, V>` is a transparent wrapper around `[Bucket<K, V>]`,
+// and reference lifetimes are bound together in function signatures.
+#[allow(unsafe_code)]
+impl<K, V> Slice<K, V> {
+ pub(super) const fn from_slice(entries: &[Bucket<K, V>]) -> &Self {
+ unsafe { &*(entries as *const [Bucket<K, V>] as *const Self) }
+ }
+
+ pub(super) fn from_mut_slice(entries: &mut [Bucket<K, V>]) -> &mut Self {
+ unsafe { &mut *(entries as *mut [Bucket<K, V>] as *mut Self) }
+ }
+
+ pub(super) fn from_boxed(entries: Box<[Bucket<K, V>]>) -> Box<Self> {
+ unsafe { Box::from_raw(Box::into_raw(entries) as *mut Self) }
+ }
+
+ fn into_boxed(self: Box<Self>) -> Box<[Bucket<K, V>]> {
+ unsafe { Box::from_raw(Box::into_raw(self) as *mut [Bucket<K, V>]) }
+ }
+}
+
+impl<K, V> Slice<K, V> {
+ pub(crate) fn into_entries(self: Box<Self>) -> Vec<Bucket<K, V>> {
+ self.into_boxed().into_vec()
+ }
+
+ /// Returns an empty slice.
+ pub const fn new<'a>() -> &'a Self {
+ Self::from_slice(&[])
+ }
+
+ /// Returns an empty mutable slice.
+ pub fn new_mut<'a>() -> &'a mut Self {
+ Self::from_mut_slice(&mut [])
+ }
+
+ /// Return the number of key-value pairs in the map slice.
+ #[inline]
+ pub const fn len(&self) -> usize {
+ self.entries.len()
+ }
+
+ /// Returns true if the map slice contains no elements.
+ #[inline]
+ pub const fn is_empty(&self) -> bool {
+ self.entries.is_empty()
+ }
+
+ /// Get a key-value pair by index.
+ ///
+ /// Valid indices are *0 <= index < self.len()*
+ pub fn get_index(&self, index: usize) -> Option<(&K, &V)> {
+ self.entries.get(index).map(Bucket::refs)
+ }
+
+ /// Get a key-value pair by index, with mutable access to the value.
+ ///
+ /// Valid indices are *0 <= index < self.len()*
+ pub fn get_index_mut(&mut self, index: usize) -> Option<(&K, &mut V)> {
+ self.entries.get_mut(index).map(Bucket::ref_mut)
+ }
+
+ /// Returns a slice of key-value pairs 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(Slice::from_slice)
+ }
+
+ /// Returns a mutable slice of key-value pairs in the given range of indices.
+ ///
+ /// Valid indices are *0 <= index < self.len()*
+ pub fn get_range_mut<R: RangeBounds<usize>>(&mut self, range: R) -> Option<&mut Self> {
+ let range = try_simplify_range(range, self.entries.len())?;
+ self.entries.get_mut(range).map(Slice::from_mut_slice)
+ }
+
+ /// Get the first key-value pair.
+ pub fn first(&self) -> Option<(&K, &V)> {
+ self.entries.first().map(Bucket::refs)
+ }
+
+ /// Get the first key-value pair, with mutable access to the value.
+ pub fn first_mut(&mut self) -> Option<(&K, &mut V)> {
+ self.entries.first_mut().map(Bucket::ref_mut)
+ }
+
+ /// Get the last key-value pair.
+ pub fn last(&self) -> Option<(&K, &V)> {
+ self.entries.last().map(Bucket::refs)
+ }
+
+ /// Get the last key-value pair, with mutable access to the value.
+ pub fn last_mut(&mut self) -> Option<(&K, &mut V)> {
+ self.entries.last_mut().map(Bucket::ref_mut)
+ }
+
+ /// 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))
+ }
+
+ /// Divides one mutable slice into two at an index.
+ ///
+ /// ***Panics*** if `index > len`.
+ pub fn split_at_mut(&mut self, index: usize) -> (&mut Self, &mut Self) {
+ let (first, second) = self.entries.split_at_mut(index);
+ (Self::from_mut_slice(first), Self::from_mut_slice(second))
+ }
+
+ /// Returns the first key-value pair and the rest of the slice,
+ /// or `None` if it is empty.
+ pub fn split_first(&self) -> Option<((&K, &V), &Self)> {
+ if let [first, rest @ ..] = &self.entries {
+ Some((first.refs(), Self::from_slice(rest)))
+ } else {
+ None
+ }
+ }
+
+ /// Returns the first key-value pair and the rest of the slice,
+ /// with mutable access to the value, or `None` if it is empty.
+ pub fn split_first_mut(&mut self) -> Option<((&K, &mut V), &mut Self)> {
+ if let [first, rest @ ..] = &mut self.entries {
+ Some((first.ref_mut(), Self::from_mut_slice(rest)))
+ } else {
+ None
+ }
+ }
+
+ /// Returns the last key-value pair and the rest of the slice,
+ /// or `None` if it is empty.
+ pub fn split_last(&self) -> Option<((&K, &V), &Self)> {
+ if let [rest @ .., last] = &self.entries {
+ Some((last.refs(), Self::from_slice(rest)))
+ } else {
+ None
+ }
+ }
+
+ /// Returns the last key-value pair and the rest of the slice,
+ /// with mutable access to the value, or `None` if it is empty.
+ pub fn split_last_mut(&mut self) -> Option<((&K, &mut V), &mut Self)> {
+ if let [rest @ .., last] = &mut self.entries {
+ Some((last.ref_mut(), Self::from_mut_slice(rest)))
+ } else {
+ None
+ }
+ }
+
+ /// Return an iterator over the key-value pairs of the map slice.
+ pub fn iter(&self) -> Iter<'_, K, V> {
+ Iter::new(&self.entries)
+ }
+
+ /// Return an iterator over the key-value pairs of the map slice.
+ pub fn iter_mut(&mut self) -> IterMut<'_, K, V> {
+ IterMut::new(&mut self.entries)
+ }
+
+ /// Return an iterator over the keys of the map slice.
+ pub fn keys(&self) -> Keys<'_, K, V> {
+ Keys::new(&self.entries)
+ }
+
+ /// Return an owning iterator over the keys of the map slice.
+ pub fn into_keys(self: Box<Self>) -> IntoKeys<K, V> {
+ IntoKeys::new(self.into_entries())
+ }
+
+ /// Return an iterator over the values of the map slice.
+ pub fn values(&self) -> Values<'_, K, V> {
+ Values::new(&self.entries)
+ }
+
+ /// Return an iterator over mutable references to the the values of the map slice.
+ pub fn values_mut(&mut self) -> ValuesMut<'_, K, V> {
+ ValuesMut::new(&mut self.entries)
+ }
+
+ /// Return an owning iterator over the values of the map slice.
+ pub fn into_values(self: Box<Self>) -> IntoValues<K, V> {
+ IntoValues::new(self.into_entries())
+ }
+
+ /// Search over a sorted map for a key.
+ ///
+ /// Returns the position where that key is present, or the position where it can be inserted to
+ /// maintain the sort. See [`slice::binary_search`] for more details.
+ ///
+ /// Computes in **O(log(n))** time, which is notably less scalable than looking the key up in
+ /// the map this is a slice from using [`IndexMap::get_index_of`], but this can also position
+ /// missing keys.
+ pub fn binary_search_keys(&self, x: &K) -> Result<usize, usize>
+ where
+ K: Ord,
+ {
+ self.binary_search_by(|p, _| p.cmp(x))
+ }
+
+ /// Search over a sorted map with a comparator function.
+ ///
+ /// Returns the position where that value is present, or the position where it can be inserted
+ /// to maintain the sort. See [`slice::binary_search_by`] for more details.
+ ///
+ /// Computes in **O(log(n))** time.
+ #[inline]
+ pub fn binary_search_by<'a, F>(&'a self, mut f: F) -> Result<usize, usize>
+ where
+ F: FnMut(&'a K, &'a V) -> Ordering,
+ {
+ self.entries.binary_search_by(move |a| f(&a.key, &a.value))
+ }
+
+ /// Search over a sorted map with an extraction function.
+ ///
+ /// Returns the position where that value is present, or the position where it can be inserted
+ /// to maintain the sort. See [`slice::binary_search_by_key`] for more details.
+ ///
+ /// Computes in **O(log(n))** time.
+ #[inline]
+ pub fn binary_search_by_key<'a, B, F>(&'a self, b: &B, mut f: F) -> Result<usize, usize>
+ where
+ F: FnMut(&'a K, &'a V) -> B,
+ B: Ord,
+ {
+ self.binary_search_by(|k, v| f(k, v).cmp(b))
+ }
+
+ /// Returns the index of the partition point of a sorted map according to the given predicate
+ /// (the index of the first element of the second partition).
+ ///
+ /// See [`slice::partition_point`] for more details.
+ ///
+ /// Computes in **O(log(n))** time.
+ #[must_use]
+ pub fn partition_point<P>(&self, mut pred: P) -> usize
+ where
+ P: FnMut(&K, &V) -> bool,
+ {
+ self.entries
+ .partition_point(move |a| pred(&a.key, &a.value))
+ }
+}
+
+impl<'a, K, V> IntoIterator for &'a Slice<K, V> {
+ type IntoIter = Iter<'a, K, V>;
+ type Item = (&'a K, &'a V);
+
+ fn into_iter(self) -> Self::IntoIter {
+ self.iter()
+ }
+}
+
+impl<'a, K, V> IntoIterator for &'a mut Slice<K, V> {
+ type IntoIter = IterMut<'a, K, V>;
+ type Item = (&'a K, &'a mut V);
+
+ fn into_iter(self) -> Self::IntoIter {
+ self.iter_mut()
+ }
+}
+
+impl<K, V> IntoIterator for Box<Slice<K, V>> {
+ type IntoIter = IntoIter<K, V>;
+ type Item = (K, V);
+
+ fn into_iter(self) -> Self::IntoIter {
+ IntoIter::new(self.into_entries())
+ }
+}
+
+impl<K, V> Default for &'_ Slice<K, V> {
+ fn default() -> Self {
+ Slice::from_slice(&[])
+ }
+}
+
+impl<K, V> Default for &'_ mut Slice<K, V> {
+ fn default() -> Self {
+ Slice::from_mut_slice(&mut [])
+ }
+}
+
+impl<K, V> Default for Box<Slice<K, V>> {
+ fn default() -> Self {
+ Slice::from_boxed(Box::default())
+ }
+}
+
+impl<K: Clone, V: Clone> Clone for Box<Slice<K, V>> {
+ fn clone(&self) -> Self {
+ Slice::from_boxed(self.entries.to_vec().into_boxed_slice())
+ }
+}
+
+impl<K: Copy, V: Copy> From<&Slice<K, V>> for Box<Slice<K, V>> {
+ fn from(slice: &Slice<K, V>) -> Self {
+ Slice::from_boxed(Box::from(&slice.entries))
+ }
+}
+
+impl<K: fmt::Debug, V: fmt::Debug> fmt::Debug for Slice<K, V> {
+ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+ f.debug_list().entries(self).finish()
+ }
+}
+
+impl<K: PartialEq, V: PartialEq> PartialEq for Slice<K, V> {
+ fn eq(&self, other: &Self) -> bool {
+ self.len() == other.len() && self.iter().eq(other)
+ }
+}
+
+impl<K: Eq, V: Eq> Eq for Slice<K, V> {}
+
+impl<K: PartialOrd, V: PartialOrd> PartialOrd for Slice<K, V> {
+ fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+ self.iter().partial_cmp(other)
+ }
+}
+
+impl<K: Ord, V: Ord> Ord for Slice<K, V> {
+ fn cmp(&self, other: &Self) -> Ordering {
+ self.iter().cmp(other)
+ }
+}
+
+impl<K: Hash, V: Hash> Hash for Slice<K, V> {
+ fn hash<H: Hasher>(&self, state: &mut H) {
+ self.len().hash(state);
+ for (key, value) in self {
+ key.hash(state);
+ value.hash(state);
+ }
+ }
+}
+
+impl<K, V> Index<usize> for Slice<K, V> {
+ type Output = V;
+
+ fn index(&self, index: usize) -> &V {
+ &self.entries[index].value
+ }
+}
+
+impl<K, V> IndexMut<usize> for Slice<K, V> {
+ fn index_mut(&mut self, index: usize) -> &mut V {
+ &mut self.entries[index].value
+ }
+}
+
+// We can't have `impl<I: RangeBounds<usize>> Index<I>` because that conflicts
+// both upstream with `Index<usize>` and downstream with `Index<&Q>`.
+// Instead, we repeat the implementations for all the core range types.
+macro_rules! impl_index {
+ ($($range:ty),*) => {$(
+ impl<K, V, S> Index<$range> for IndexMap<K, V, S> {
+ type Output = Slice<K, V>;
+
+ fn index(&self, range: $range) -> &Self::Output {
+ Slice::from_slice(&self.as_entries()[range])
+ }
+ }
+
+ impl<K, V, S> IndexMut<$range> for IndexMap<K, V, S> {
+ fn index_mut(&mut self, range: $range) -> &mut Self::Output {
+ Slice::from_mut_slice(&mut self.as_entries_mut()[range])
+ }
+ }
+
+ impl<K, V> Index<$range> for Slice<K, V> {
+ type Output = Slice<K, V>;
+
+ fn index(&self, range: $range) -> &Self {
+ Self::from_slice(&self.entries[range])
+ }
+ }
+
+ impl<K, V> IndexMut<$range> for Slice<K, V> {
+ fn index_mut(&mut self, range: $range) -> &mut Self {
+ Self::from_mut_slice(&mut 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::*;
+
+ #[test]
+ fn slice_index() {
+ fn check(
+ vec_slice: &[(i32, i32)],
+ map_slice: &Slice<i32, i32>,
+ sub_slice: &Slice<i32, i32>,
+ ) {
+ assert_eq!(map_slice as *const _, sub_slice as *const _);
+ itertools::assert_equal(
+ vec_slice.iter().copied(),
+ map_slice.iter().map(|(&k, &v)| (k, v)),
+ );
+ itertools::assert_equal(vec_slice.iter().map(|(k, _)| k), map_slice.keys());
+ itertools::assert_equal(vec_slice.iter().map(|(_, v)| v), map_slice.values());
+ }
+
+ let vec: Vec<(i32, i32)> = (0..10).map(|i| (i, i * i)).collect();
+ let map: IndexMap<i32, i32> = vec.iter().cloned().collect();
+ let slice = map.as_slice();
+
+ // RangeFull
+ check(&vec[..], &map[..], &slice[..]);
+
+ for i in 0usize..10 {
+ // Index
+ assert_eq!(vec[i].1, map[i]);
+ assert_eq!(vec[i].1, slice[i]);
+ assert_eq!(map[&(i as i32)], map[i]);
+ assert_eq!(map[&(i as i32)], slice[i]);
+
+ // RangeFrom
+ check(&vec[i..], &map[i..], &slice[i..]);
+
+ // RangeTo
+ check(&vec[..i], &map[..i], &slice[..i]);
+
+ // RangeToInclusive
+ check(&vec[..=i], &map[..=i], &slice[..=i]);
+
+ // (Bound<usize>, Bound<usize>)
+ let bounds = (Bound::Excluded(i), Bound::Unbounded);
+ check(&vec[i + 1..], &map[bounds], &slice[bounds]);
+
+ for j in i..=10 {
+ // Range
+ check(&vec[i..j], &map[i..j], &slice[i..j]);
+ }
+
+ for j in i..10 {
+ // RangeInclusive
+ check(&vec[i..=j], &map[i..=j], &slice[i..=j]);
+ }
+ }
+ }
+
+ #[test]
+ fn slice_index_mut() {
+ fn check_mut(
+ vec_slice: &[(i32, i32)],
+ map_slice: &mut Slice<i32, i32>,
+ sub_slice: &mut Slice<i32, i32>,
+ ) {
+ assert_eq!(map_slice, sub_slice);
+ itertools::assert_equal(
+ vec_slice.iter().copied(),
+ map_slice.iter_mut().map(|(&k, &mut v)| (k, v)),
+ );
+ itertools::assert_equal(
+ vec_slice.iter().map(|&(_, v)| v),
+ map_slice.values_mut().map(|&mut v| v),
+ );
+ }
+
+ let vec: Vec<(i32, i32)> = (0..10).map(|i| (i, i * i)).collect();
+ let mut map: IndexMap<i32, i32> = vec.iter().cloned().collect();
+ let mut map2 = map.clone();
+ let slice = map2.as_mut_slice();
+
+ // RangeFull
+ check_mut(&vec[..], &mut map[..], &mut slice[..]);
+
+ for i in 0usize..10 {
+ // IndexMut
+ assert_eq!(&mut map[i], &mut slice[i]);
+
+ // RangeFrom
+ check_mut(&vec[i..], &mut map[i..], &mut slice[i..]);
+
+ // RangeTo
+ check_mut(&vec[..i], &mut map[..i], &mut slice[..i]);
+
+ // RangeToInclusive
+ check_mut(&vec[..=i], &mut map[..=i], &mut slice[..=i]);
+
+ // (Bound<usize>, Bound<usize>)
+ let bounds = (Bound::Excluded(i), Bound::Unbounded);
+ check_mut(&vec[i + 1..], &mut map[bounds], &mut slice[bounds]);
+
+ for j in i..=10 {
+ // Range
+ check_mut(&vec[i..j], &mut map[i..j], &mut slice[i..j]);
+ }
+
+ for j in i..10 {
+ // RangeInclusive
+ check_mut(&vec[i..=j], &mut map[i..=j], &mut slice[i..=j]);
+ }
+ }
+ }
+}
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