/rust/registry/src/index.crates.io-6f17d22bba15001f/indexmap-2.10.0/src/set/slice.rs
Line | Count | Source (jump to first uncovered line) |
1 | | use super::{Bucket, IndexSet, IntoIter, Iter}; |
2 | | use crate::util::{slice_eq, try_simplify_range}; |
3 | | |
4 | | use alloc::boxed::Box; |
5 | | use alloc::vec::Vec; |
6 | | use core::cmp::Ordering; |
7 | | use core::fmt; |
8 | | use core::hash::{Hash, Hasher}; |
9 | | use core::ops::{self, Bound, Index, RangeBounds}; |
10 | | |
11 | | /// A dynamically-sized slice of values in an [`IndexSet`]. |
12 | | /// |
13 | | /// This supports indexed operations much like a `[T]` slice, |
14 | | /// but not any hashed operations on the values. |
15 | | /// |
16 | | /// Unlike `IndexSet`, `Slice` does consider the order for [`PartialEq`] |
17 | | /// and [`Eq`], and it also implements [`PartialOrd`], [`Ord`], and [`Hash`]. |
18 | | #[repr(transparent)] |
19 | | pub struct Slice<T> { |
20 | | pub(crate) entries: [Bucket<T>], |
21 | | } |
22 | | |
23 | | // SAFETY: `Slice<T>` is a transparent wrapper around `[Bucket<T>]`, |
24 | | // and reference lifetimes are bound together in function signatures. |
25 | | #[allow(unsafe_code)] |
26 | | impl<T> Slice<T> { |
27 | 0 | pub(super) const fn from_slice(entries: &[Bucket<T>]) -> &Self { |
28 | 0 | unsafe { &*(entries as *const [Bucket<T>] as *const Self) } |
29 | 0 | } |
30 | | |
31 | 0 | pub(super) fn from_boxed(entries: Box<[Bucket<T>]>) -> Box<Self> { |
32 | 0 | unsafe { Box::from_raw(Box::into_raw(entries) as *mut Self) } |
33 | 0 | } |
34 | | |
35 | 0 | fn into_boxed(self: Box<Self>) -> Box<[Bucket<T>]> { |
36 | 0 | unsafe { Box::from_raw(Box::into_raw(self) as *mut [Bucket<T>]) } |
37 | 0 | } |
38 | | } |
39 | | |
40 | | impl<T> Slice<T> { |
41 | 0 | pub(crate) fn into_entries(self: Box<Self>) -> Vec<Bucket<T>> { |
42 | 0 | self.into_boxed().into_vec() |
43 | 0 | } |
44 | | |
45 | | /// Returns an empty slice. |
46 | 0 | pub const fn new<'a>() -> &'a Self { |
47 | 0 | Self::from_slice(&[]) |
48 | 0 | } |
49 | | |
50 | | /// Return the number of elements in the set slice. |
51 | 0 | pub const fn len(&self) -> usize { |
52 | 0 | self.entries.len() |
53 | 0 | } |
54 | | |
55 | | /// Returns true if the set slice contains no elements. |
56 | 0 | pub const fn is_empty(&self) -> bool { |
57 | 0 | self.entries.is_empty() |
58 | 0 | } |
59 | | |
60 | | /// Get a value by index. |
61 | | /// |
62 | | /// Valid indices are `0 <= index < self.len()`. |
63 | 0 | pub fn get_index(&self, index: usize) -> Option<&T> { |
64 | 0 | self.entries.get(index).map(Bucket::key_ref) |
65 | 0 | } |
66 | | |
67 | | /// Returns a slice of values in the given range of indices. |
68 | | /// |
69 | | /// Valid indices are `0 <= index < self.len()`. |
70 | 0 | pub fn get_range<R: RangeBounds<usize>>(&self, range: R) -> Option<&Self> { |
71 | 0 | let range = try_simplify_range(range, self.entries.len())?; |
72 | 0 | self.entries.get(range).map(Self::from_slice) |
73 | 0 | } |
74 | | |
75 | | /// Get the first value. |
76 | 0 | pub fn first(&self) -> Option<&T> { |
77 | 0 | self.entries.first().map(Bucket::key_ref) |
78 | 0 | } |
79 | | |
80 | | /// Get the last value. |
81 | 0 | pub fn last(&self) -> Option<&T> { |
82 | 0 | self.entries.last().map(Bucket::key_ref) |
83 | 0 | } |
84 | | |
85 | | /// Divides one slice into two at an index. |
86 | | /// |
87 | | /// ***Panics*** if `index > len`. |
88 | | #[track_caller] |
89 | 0 | pub fn split_at(&self, index: usize) -> (&Self, &Self) { |
90 | 0 | let (first, second) = self.entries.split_at(index); |
91 | 0 | (Self::from_slice(first), Self::from_slice(second)) |
92 | 0 | } |
93 | | |
94 | | /// Returns the first value and the rest of the slice, |
95 | | /// or `None` if it is empty. |
96 | 0 | pub fn split_first(&self) -> Option<(&T, &Self)> { |
97 | 0 | if let [first, rest @ ..] = &self.entries { |
98 | 0 | Some((&first.key, Self::from_slice(rest))) |
99 | | } else { |
100 | 0 | None |
101 | | } |
102 | 0 | } |
103 | | |
104 | | /// Returns the last value and the rest of the slice, |
105 | | /// or `None` if it is empty. |
106 | 0 | pub fn split_last(&self) -> Option<(&T, &Self)> { |
107 | 0 | if let [rest @ .., last] = &self.entries { |
108 | 0 | Some((&last.key, Self::from_slice(rest))) |
109 | | } else { |
110 | 0 | None |
111 | | } |
112 | 0 | } |
113 | | |
114 | | /// Return an iterator over the values of the set slice. |
115 | 0 | pub fn iter(&self) -> Iter<'_, T> { |
116 | 0 | Iter::new(&self.entries) |
117 | 0 | } |
118 | | |
119 | | /// Search over a sorted set for a value. |
120 | | /// |
121 | | /// Returns the position where that value is present, or the position where it can be inserted |
122 | | /// to maintain the sort. See [`slice::binary_search`] for more details. |
123 | | /// |
124 | | /// Computes in **O(log(n))** time, which is notably less scalable than looking the value up in |
125 | | /// the set this is a slice from using [`IndexSet::get_index_of`], but this can also position |
126 | | /// missing values. |
127 | 0 | pub fn binary_search(&self, x: &T) -> Result<usize, usize> |
128 | 0 | where |
129 | 0 | T: Ord, |
130 | 0 | { |
131 | 0 | self.binary_search_by(|p| p.cmp(x)) |
132 | 0 | } |
133 | | |
134 | | /// Search over a sorted set with a comparator function. |
135 | | /// |
136 | | /// Returns the position where that value is present, or the position where it can be inserted |
137 | | /// to maintain the sort. See [`slice::binary_search_by`] for more details. |
138 | | /// |
139 | | /// Computes in **O(log(n))** time. |
140 | | #[inline] |
141 | 0 | pub fn binary_search_by<'a, F>(&'a self, mut f: F) -> Result<usize, usize> |
142 | 0 | where |
143 | 0 | F: FnMut(&'a T) -> Ordering, |
144 | 0 | { |
145 | 0 | self.entries.binary_search_by(move |a| f(&a.key)) |
146 | 0 | } |
147 | | |
148 | | /// Search over a sorted set with an extraction function. |
149 | | /// |
150 | | /// Returns the position where that value is present, or the position where it can be inserted |
151 | | /// to maintain the sort. See [`slice::binary_search_by_key`] for more details. |
152 | | /// |
153 | | /// Computes in **O(log(n))** time. |
154 | | #[inline] |
155 | 0 | pub fn binary_search_by_key<'a, B, F>(&'a self, b: &B, mut f: F) -> Result<usize, usize> |
156 | 0 | where |
157 | 0 | F: FnMut(&'a T) -> B, |
158 | 0 | B: Ord, |
159 | 0 | { |
160 | 0 | self.binary_search_by(|k| f(k).cmp(b)) |
161 | 0 | } |
162 | | |
163 | | /// Returns the index of the partition point of a sorted set according to the given predicate |
164 | | /// (the index of the first element of the second partition). |
165 | | /// |
166 | | /// See [`slice::partition_point`] for more details. |
167 | | /// |
168 | | /// Computes in **O(log(n))** time. |
169 | | #[must_use] |
170 | 0 | pub fn partition_point<P>(&self, mut pred: P) -> usize |
171 | 0 | where |
172 | 0 | P: FnMut(&T) -> bool, |
173 | 0 | { |
174 | 0 | self.entries.partition_point(move |a| pred(&a.key)) |
175 | 0 | } |
176 | | } |
177 | | |
178 | | impl<'a, T> IntoIterator for &'a Slice<T> { |
179 | | type IntoIter = Iter<'a, T>; |
180 | | type Item = &'a T; |
181 | | |
182 | 0 | fn into_iter(self) -> Self::IntoIter { |
183 | 0 | self.iter() |
184 | 0 | } |
185 | | } |
186 | | |
187 | | impl<T> IntoIterator for Box<Slice<T>> { |
188 | | type IntoIter = IntoIter<T>; |
189 | | type Item = T; |
190 | | |
191 | 0 | fn into_iter(self) -> Self::IntoIter { |
192 | 0 | IntoIter::new(self.into_entries()) |
193 | 0 | } |
194 | | } |
195 | | |
196 | | impl<T> Default for &'_ Slice<T> { |
197 | 0 | fn default() -> Self { |
198 | 0 | Slice::from_slice(&[]) |
199 | 0 | } |
200 | | } |
201 | | |
202 | | impl<T> Default for Box<Slice<T>> { |
203 | 0 | fn default() -> Self { |
204 | 0 | Slice::from_boxed(Box::default()) |
205 | 0 | } |
206 | | } |
207 | | |
208 | | impl<T: Clone> Clone for Box<Slice<T>> { |
209 | 0 | fn clone(&self) -> Self { |
210 | 0 | Slice::from_boxed(self.entries.to_vec().into_boxed_slice()) |
211 | 0 | } |
212 | | } |
213 | | |
214 | | impl<T: Copy> From<&Slice<T>> for Box<Slice<T>> { |
215 | 0 | fn from(slice: &Slice<T>) -> Self { |
216 | 0 | Slice::from_boxed(Box::from(&slice.entries)) |
217 | 0 | } |
218 | | } |
219 | | |
220 | | impl<T: fmt::Debug> fmt::Debug for Slice<T> { |
221 | 0 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
222 | 0 | f.debug_list().entries(self).finish() |
223 | 0 | } |
224 | | } |
225 | | |
226 | | impl<T, U> PartialEq<Slice<U>> for Slice<T> |
227 | | where |
228 | | T: PartialEq<U>, |
229 | | { |
230 | 0 | fn eq(&self, other: &Slice<U>) -> bool { |
231 | 0 | slice_eq(&self.entries, &other.entries, |b1, b2| b1.key == b2.key) |
232 | 0 | } |
233 | | } |
234 | | |
235 | | impl<T, U> PartialEq<[U]> for Slice<T> |
236 | | where |
237 | | T: PartialEq<U>, |
238 | | { |
239 | 0 | fn eq(&self, other: &[U]) -> bool { |
240 | 0 | slice_eq(&self.entries, other, |b, o| b.key == *o) |
241 | 0 | } |
242 | | } |
243 | | |
244 | | impl<T, U> PartialEq<Slice<U>> for [T] |
245 | | where |
246 | | T: PartialEq<U>, |
247 | | { |
248 | 0 | fn eq(&self, other: &Slice<U>) -> bool { |
249 | 0 | slice_eq(self, &other.entries, |o, b| *o == b.key) |
250 | 0 | } |
251 | | } |
252 | | |
253 | | impl<T, U, const N: usize> PartialEq<[U; N]> for Slice<T> |
254 | | where |
255 | | T: PartialEq<U>, |
256 | | { |
257 | 0 | fn eq(&self, other: &[U; N]) -> bool { |
258 | 0 | <Self as PartialEq<[U]>>::eq(self, other) |
259 | 0 | } |
260 | | } |
261 | | |
262 | | impl<T, const N: usize, U> PartialEq<Slice<U>> for [T; N] |
263 | | where |
264 | | T: PartialEq<U>, |
265 | | { |
266 | 0 | fn eq(&self, other: &Slice<U>) -> bool { |
267 | 0 | <[T] as PartialEq<Slice<U>>>::eq(self, other) |
268 | 0 | } |
269 | | } |
270 | | |
271 | | impl<T: Eq> Eq for Slice<T> {} |
272 | | |
273 | | impl<T: PartialOrd> PartialOrd for Slice<T> { |
274 | 0 | fn partial_cmp(&self, other: &Self) -> Option<Ordering> { |
275 | 0 | self.iter().partial_cmp(other) |
276 | 0 | } |
277 | | } |
278 | | |
279 | | impl<T: Ord> Ord for Slice<T> { |
280 | 0 | fn cmp(&self, other: &Self) -> Ordering { |
281 | 0 | self.iter().cmp(other) |
282 | 0 | } |
283 | | } |
284 | | |
285 | | impl<T: Hash> Hash for Slice<T> { |
286 | 0 | fn hash<H: Hasher>(&self, state: &mut H) { |
287 | 0 | self.len().hash(state); |
288 | 0 | for value in self { |
289 | 0 | value.hash(state); |
290 | 0 | } |
291 | 0 | } |
292 | | } |
293 | | |
294 | | impl<T> Index<usize> for Slice<T> { |
295 | | type Output = T; |
296 | | |
297 | 0 | fn index(&self, index: usize) -> &Self::Output { |
298 | 0 | &self.entries[index].key |
299 | 0 | } |
300 | | } |
301 | | |
302 | | // We can't have `impl<I: RangeBounds<usize>> Index<I>` because that conflicts with `Index<usize>`. |
303 | | // Instead, we repeat the implementations for all the core range types. |
304 | | macro_rules! impl_index { |
305 | | ($($range:ty),*) => {$( |
306 | | impl<T, S> Index<$range> for IndexSet<T, S> { |
307 | | type Output = Slice<T>; |
308 | | |
309 | 0 | fn index(&self, range: $range) -> &Self::Output { |
310 | 0 | Slice::from_slice(&self.as_entries()[range]) |
311 | 0 | } Unexecuted instantiation: <indexmap::set::IndexSet<_, _> as core::ops::index::Index<core::ops::range::Range<usize>>>::index Unexecuted instantiation: <indexmap::set::IndexSet<_, _> as core::ops::index::Index<core::ops::range::RangeFrom<usize>>>::index Unexecuted instantiation: <indexmap::set::IndexSet<_, _> as core::ops::index::Index<core::ops::range::RangeFull>>::index Unexecuted instantiation: <indexmap::set::IndexSet<_, _> as core::ops::index::Index<core::ops::range::RangeInclusive<usize>>>::index Unexecuted instantiation: <indexmap::set::IndexSet<_, _> as core::ops::index::Index<core::ops::range::RangeTo<usize>>>::index Unexecuted instantiation: <indexmap::set::IndexSet<_, _> as core::ops::index::Index<core::ops::range::RangeToInclusive<usize>>>::index Unexecuted instantiation: <indexmap::set::IndexSet<_, _> as core::ops::index::Index<(core::ops::range::Bound<usize>, core::ops::range::Bound<usize>)>>::index |
312 | | } |
313 | | |
314 | | impl<T> Index<$range> for Slice<T> { |
315 | | type Output = Self; |
316 | | |
317 | 0 | fn index(&self, range: $range) -> &Self::Output { |
318 | 0 | Slice::from_slice(&self.entries[range]) |
319 | 0 | } Unexecuted instantiation: <indexmap::set::slice::Slice<_> as core::ops::index::Index<core::ops::range::Range<usize>>>::index Unexecuted instantiation: <indexmap::set::slice::Slice<_> as core::ops::index::Index<core::ops::range::RangeFrom<usize>>>::index Unexecuted instantiation: <indexmap::set::slice::Slice<_> as core::ops::index::Index<core::ops::range::RangeFull>>::index Unexecuted instantiation: <indexmap::set::slice::Slice<_> as core::ops::index::Index<core::ops::range::RangeInclusive<usize>>>::index Unexecuted instantiation: <indexmap::set::slice::Slice<_> as core::ops::index::Index<core::ops::range::RangeTo<usize>>>::index Unexecuted instantiation: <indexmap::set::slice::Slice<_> as core::ops::index::Index<core::ops::range::RangeToInclusive<usize>>>::index Unexecuted instantiation: <indexmap::set::slice::Slice<_> as core::ops::index::Index<(core::ops::range::Bound<usize>, core::ops::range::Bound<usize>)>>::index |
320 | | } |
321 | | )*} |
322 | | } |
323 | | impl_index!( |
324 | | ops::Range<usize>, |
325 | | ops::RangeFrom<usize>, |
326 | | ops::RangeFull, |
327 | | ops::RangeInclusive<usize>, |
328 | | ops::RangeTo<usize>, |
329 | | ops::RangeToInclusive<usize>, |
330 | | (Bound<usize>, Bound<usize>) |
331 | | ); |
332 | | |
333 | | #[cfg(test)] |
334 | | mod tests { |
335 | | use super::*; |
336 | | |
337 | | #[test] |
338 | | fn slice_index() { |
339 | | fn check(vec_slice: &[i32], set_slice: &Slice<i32>, sub_slice: &Slice<i32>) { |
340 | | assert_eq!(set_slice as *const _, sub_slice as *const _); |
341 | | itertools::assert_equal(vec_slice, set_slice); |
342 | | } |
343 | | |
344 | | let vec: Vec<i32> = (0..10).map(|i| i * i).collect(); |
345 | | let set: IndexSet<i32> = vec.iter().cloned().collect(); |
346 | | let slice = set.as_slice(); |
347 | | |
348 | | // RangeFull |
349 | | check(&vec[..], &set[..], &slice[..]); |
350 | | |
351 | | for i in 0usize..10 { |
352 | | // Index |
353 | | assert_eq!(vec[i], set[i]); |
354 | | assert_eq!(vec[i], slice[i]); |
355 | | |
356 | | // RangeFrom |
357 | | check(&vec[i..], &set[i..], &slice[i..]); |
358 | | |
359 | | // RangeTo |
360 | | check(&vec[..i], &set[..i], &slice[..i]); |
361 | | |
362 | | // RangeToInclusive |
363 | | check(&vec[..=i], &set[..=i], &slice[..=i]); |
364 | | |
365 | | // (Bound<usize>, Bound<usize>) |
366 | | let bounds = (Bound::Excluded(i), Bound::Unbounded); |
367 | | check(&vec[i + 1..], &set[bounds], &slice[bounds]); |
368 | | |
369 | | for j in i..=10 { |
370 | | // Range |
371 | | check(&vec[i..j], &set[i..j], &slice[i..j]); |
372 | | } |
373 | | |
374 | | for j in i..10 { |
375 | | // RangeInclusive |
376 | | check(&vec[i..=j], &set[i..=j], &slice[i..=j]); |
377 | | } |
378 | | } |
379 | | } |
380 | | } |