/rust/registry/src/index.crates.io-6f17d22bba15001f/rayon-1.10.0/src/iter/update.rs

Source (jump to first uncovered line)
use super::plumbing::*;
use super::*;

use std::fmt::{self, Debug};

/// `Update` is an iterator that mutates the elements of an
/// underlying iterator before they are yielded.
///
/// This struct is created by the [`update()`] method on [`ParallelIterator`]
///
/// [`update()`]: trait.ParallelIterator.html#method.update
/// [`ParallelIterator`]: trait.ParallelIterator.html
#[must_use = "iterator adaptors are lazy and do nothing unless consumed"]
#[derive(Clone)]
pub struct Update<I: ParallelIterator, F> {
    base: I,
    update_op: F,
}

impl<I: ParallelIterator + Debug, F> Debug for Update<I, F> {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        f.debug_struct("Update").field("base", &self.base).finish()
    }
}

impl<I, F> Update<I, F>
where
    I: ParallelIterator,
{
    /// Creates a new `Update` iterator.
    pub(super) fn new(base: I, update_op: F) -> Self {
        Update { base, update_op }
    }
}

impl<I, F> ParallelIterator for Update<I, F>
where
    I: ParallelIterator,
    F: Fn(&mut I::Item) + Send + Sync,
{
    type Item = I::Item;

    fn drive_unindexed<C>(self, consumer: C) -> C::Result
    where
        C: UnindexedConsumer<Self::Item>,
    {
        let consumer1 = UpdateConsumer::new(consumer, &self.update_op);
        self.base.drive_unindexed(consumer1)
    }

    fn opt_len(&self) -> Option<usize> {
        self.base.opt_len()
    }
}

impl<I, F> IndexedParallelIterator for Update<I, F>
where
    I: IndexedParallelIterator,
    F: Fn(&mut I::Item) + Send + Sync,
{
    fn drive<C>(self, consumer: C) -> C::Result
    where
        C: Consumer<Self::Item>,
    {
        let consumer1 = UpdateConsumer::new(consumer, &self.update_op);
        self.base.drive(consumer1)
    }

    fn len(&self) -> usize {
        self.base.len()
    }

    fn with_producer<CB>(self, callback: CB) -> CB::Output
    where
        CB: ProducerCallback<Self::Item>,
    {
        return self.base.with_producer(Callback {
            callback,
            update_op: self.update_op,
        });

        struct Callback<CB, F> {
            callback: CB,
            update_op: F,
        }

        impl<T, F, CB> ProducerCallback<T> for Callback<CB, F>
        where
            CB: ProducerCallback<T>,
            F: Fn(&mut T) + Send + Sync,
        {
            type Output = CB::Output;

            fn callback<P>(self, base: P) -> CB::Output
            where
                P: Producer<Item = T>,
            {
                let producer = UpdateProducer {
                    base,
                    update_op: &self.update_op,
                };
                self.callback.callback(producer)
            }
        }
    }
}

/// ////////////////////////////////////////////////////////////////////////

struct UpdateProducer<'f, P, F> {
    base: P,
    update_op: &'f F,
}

impl<'f, P, F> Producer for UpdateProducer<'f, P, F>
where
    P: Producer,
    F: Fn(&mut P::Item) + Send + Sync,
{
    type Item = P::Item;
    type IntoIter = UpdateSeq<P::IntoIter, &'f F>;

    fn into_iter(self) -> Self::IntoIter {
        UpdateSeq {
            base: self.base.into_iter(),
            update_op: self.update_op,
        }
    }

    fn min_len(&self) -> usize {
        self.base.min_len()
    }
    fn max_len(&self) -> usize {
        self.base.max_len()
    }

    fn split_at(self, index: usize) -> (Self, Self) {
        let (left, right) = self.base.split_at(index);
        (
            UpdateProducer {
                base: left,
                update_op: self.update_op,
            },
            UpdateProducer {
                base: right,
                update_op: self.update_op,
            },
        )
    }

    fn fold_with<G>(self, folder: G) -> G
    where
        G: Folder<Self::Item>,
    {
        let folder1 = UpdateFolder {
            base: folder,
            update_op: self.update_op,
        };
        self.base.fold_with(folder1).base
    }
}

/// ////////////////////////////////////////////////////////////////////////
/// Consumer implementation

struct UpdateConsumer<'f, C, F> {
    base: C,
    update_op: &'f F,
}

impl<'f, C, F> UpdateConsumer<'f, C, F> {
    fn new(base: C, update_op: &'f F) -> Self {
        UpdateConsumer { base, update_op }
    }
}

impl<'f, T, C, F> Consumer<T> for UpdateConsumer<'f, C, F>
where
    C: Consumer<T>,
    F: Fn(&mut T) + Send + Sync,
{
    type Folder = UpdateFolder<'f, C::Folder, F>;
    type Reducer = C::Reducer;
    type Result = C::Result;

    fn split_at(self, index: usize) -> (Self, Self, Self::Reducer) {
        let (left, right, reducer) = self.base.split_at(index);
        (
            UpdateConsumer::new(left, self.update_op),
            UpdateConsumer::new(right, self.update_op),
            reducer,
        )
    }

    fn into_folder(self) -> Self::Folder {
        UpdateFolder {
            base: self.base.into_folder(),
            update_op: self.update_op,
        }
    }

    fn full(&self) -> bool {
        self.base.full()
    }
}

impl<'f, T, C, F> UnindexedConsumer<T> for UpdateConsumer<'f, C, F>
where
    C: UnindexedConsumer<T>,
    F: Fn(&mut T) + Send + Sync,
{
    fn split_off_left(&self) -> Self {
        UpdateConsumer::new(self.base.split_off_left(), self.update_op)
    }

    fn to_reducer(&self) -> Self::Reducer {
        self.base.to_reducer()
    }
}

struct UpdateFolder<'f, C, F> {
    base: C,
    update_op: &'f F,
}

fn apply<T>(update_op: impl Fn(&mut T)) -> impl Fn(T) -> T {
    move |mut item| {
        update_op(&mut item);
        item
    }
}

impl<'f, T, C, F> Folder<T> for UpdateFolder<'f, C, F>
where
    C: Folder<T>,
    F: Fn(&mut T),
{
    type Result = C::Result;

    fn consume(self, mut item: T) -> Self {
        (self.update_op)(&mut item);

        UpdateFolder {
            base: self.base.consume(item),
            update_op: self.update_op,
        }
    }

    fn consume_iter<I>(mut self, iter: I) -> Self
    where
        I: IntoIterator<Item = T>,
    {
        let update_op = self.update_op;
        self.base = self
            .base
            .consume_iter(iter.into_iter().map(apply(update_op)));
        self
    }

    fn complete(self) -> C::Result {
        self.base.complete()
    }

    fn full(&self) -> bool {
        self.base.full()
    }
}

/// Standard Update adaptor, based on `itertools::adaptors::Update`
#[must_use = "iterator adaptors are lazy and do nothing unless consumed"]
#[derive(Debug, Clone)]
struct UpdateSeq<I, F> {
    base: I,
    update_op: F,
}

impl<I, F> Iterator for UpdateSeq<I, F>
where
    I: Iterator,
    F: Fn(&mut I::Item),
{
    type Item = I::Item;

    fn next(&mut self) -> Option<Self::Item> {
        let mut v = self.base.next()?;
        (self.update_op)(&mut v);
        Some(v)
    }

    fn size_hint(&self) -> (usize, Option<usize>) {
        self.base.size_hint()
    }

    fn fold<Acc, G>(self, init: Acc, g: G) -> Acc
    where
        G: FnMut(Acc, Self::Item) -> Acc,
    {
        self.base.map(apply(self.update_op)).fold(init, g)
    }

    // if possible, re-use inner iterator specializations in collect
    fn collect<C>(self) -> C
    where
        C: ::std::iter::FromIterator<Self::Item>,
    {
        self.base.map(apply(self.update_op)).collect()
    }
}

impl<I, F> ExactSizeIterator for UpdateSeq<I, F>
where
    I: ExactSizeIterator,
    F: Fn(&mut I::Item),
{
}

impl<I, F> DoubleEndedIterator for UpdateSeq<I, F>
where
    I: DoubleEndedIterator,
    F: Fn(&mut I::Item),
{
    fn next_back(&mut self) -> Option<Self::Item> {
        let mut v = self.base.next_back()?;
        (self.update_op)(&mut v);
        Some(v)
    }
}

Coverage Report

Created: 2025-07-04 06:57

Line	Count	Source (jump to first uncovered line)
1		use super::plumbing::*;
2		use super::*;
3
4		use std::fmt::{self, Debug};
5
6		/// `Update` is an iterator that mutates the elements of an
7		/// underlying iterator before they are yielded.
8		///
9		/// This struct is created by the [`update()`] method on [`ParallelIterator`]
10		///
11		/// [`update()`]: trait.ParallelIterator.html#method.update
12		/// [`ParallelIterator`]: trait.ParallelIterator.html
13		#[must_use = "iterator adaptors are lazy and do nothing unless consumed"]
14		#[derive(Clone)]
15		pub struct Update<I: ParallelIterator, F> {
16		base: I,
17		update_op: F,
18		}
19
20		impl<I: ParallelIterator + Debug, F> Debug for Update<I, F> {
21	0	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
22	0	f.debug_struct("Update").field("base", &self.base).finish()
23	0	}
24		}
25
26		impl<I, F> Update<I, F>
27		where
28		I: ParallelIterator,
29		{
30		/// Creates a new `Update` iterator.
31	0	pub(super) fn new(base: I, update_op: F) -> Self {
32	0	Update { base, update_op }
33	0	}
34		}
35
36		impl<I, F> ParallelIterator for Update<I, F>
37		where
38		I: ParallelIterator,
39		F: Fn(&mut I::Item) + Send + Sync,
40		{
41		type Item = I::Item;
42
43	0	fn drive_unindexed<C>(self, consumer: C) -> C::Result
44	0	where
45	0	C: UnindexedConsumer<Self::Item>,
46	0	{
47	0	let consumer1 = UpdateConsumer::new(consumer, &self.update_op);
48	0	self.base.drive_unindexed(consumer1)
49	0	}
50
51	0	fn opt_len(&self) -> Option<usize> {
52	0	self.base.opt_len()
53	0	}
54		}
55
56		impl<I, F> IndexedParallelIterator for Update<I, F>
57		where
58		I: IndexedParallelIterator,
59		F: Fn(&mut I::Item) + Send + Sync,
60		{
61	0	fn drive<C>(self, consumer: C) -> C::Result
62	0	where
63	0	C: Consumer<Self::Item>,
64	0	{
65	0	let consumer1 = UpdateConsumer::new(consumer, &self.update_op);
66	0	self.base.drive(consumer1)
67	0	}
68
69	0	fn len(&self) -> usize {
70	0	self.base.len()
71	0	}
72
73	0	fn with_producer<CB>(self, callback: CB) -> CB::Output
74	0	where
75	0	CB: ProducerCallback<Self::Item>,
76	0	{
77	0	return self.base.with_producer(Callback {
78	0	callback,
79	0	update_op: self.update_op,
80	0	});
81
82		struct Callback<CB, F> {
83		callback: CB,
84		update_op: F,
85		}
86
87		impl<T, F, CB> ProducerCallback<T> for Callback<CB, F>
88		where
89		CB: ProducerCallback<T>,
90		F: Fn(&mut T) + Send + Sync,
91		{
92		type Output = CB::Output;
93
94	0	fn callback<P>(self, base: P) -> CB::Output
95	0	where
96	0	P: Producer<Item = T>,
97	0	{
98	0	let producer = UpdateProducer {
99	0	base,
100	0	update_op: &self.update_op,
101	0	};
102	0	self.callback.callback(producer)
103	0	}
104		}
105	0	}
106		}
107
108		/// ////////////////////////////////////////////////////////////////////////
109
110		struct UpdateProducer<'f, P, F> {
111		base: P,
112		update_op: &'f F,
113		}
114
115		impl<'f, P, F> Producer for UpdateProducer<'f, P, F>
116		where
117		P: Producer,
118		F: Fn(&mut P::Item) + Send + Sync,
119		{
120		type Item = P::Item;
121		type IntoIter = UpdateSeq<P::IntoIter, &'f F>;
122
123	0	fn into_iter(self) -> Self::IntoIter {
124	0	UpdateSeq {
125	0	base: self.base.into_iter(),
126	0	update_op: self.update_op,
127	0	}
128	0	}
129
130	0	fn min_len(&self) -> usize {
131	0	self.base.min_len()
132	0	}
133	0	fn max_len(&self) -> usize {
134	0	self.base.max_len()
135	0	}
136
137	0	fn split_at(self, index: usize) -> (Self, Self) {
138	0	let (left, right) = self.base.split_at(index);
139	0	(
140	0	UpdateProducer {
141	0	base: left,
142	0	update_op: self.update_op,
143	0	},
144	0	UpdateProducer {
145	0	base: right,
146	0	update_op: self.update_op,
147	0	},
148	0	)
149	0	}
150
151	0	fn fold_with<G>(self, folder: G) -> G
152	0	where
153	0	G: Folder<Self::Item>,
154	0	{
155	0	let folder1 = UpdateFolder {
156	0	base: folder,
157	0	update_op: self.update_op,
158	0	};
159	0	self.base.fold_with(folder1).base
160	0	}
161		}
162
163		/// ////////////////////////////////////////////////////////////////////////
164		/// Consumer implementation
165
166		struct UpdateConsumer<'f, C, F> {
167		base: C,
168		update_op: &'f F,
169		}
170
171		impl<'f, C, F> UpdateConsumer<'f, C, F> {
172	0	fn new(base: C, update_op: &'f F) -> Self {
173	0	UpdateConsumer { base, update_op }
174	0	}
175		}
176
177		impl<'f, T, C, F> Consumer<T> for UpdateConsumer<'f, C, F>
178		where
179		C: Consumer<T>,
180		F: Fn(&mut T) + Send + Sync,
181		{
182		type Folder = UpdateFolder<'f, C::Folder, F>;
183		type Reducer = C::Reducer;
184		type Result = C::Result;
185
186	0	fn split_at(self, index: usize) -> (Self, Self, Self::Reducer) {
187	0	let (left, right, reducer) = self.base.split_at(index);
188	0	(
189	0	UpdateConsumer::new(left, self.update_op),
190	0	UpdateConsumer::new(right, self.update_op),
191	0	reducer,
192	0	)
193	0	}
194
195	0	fn into_folder(self) -> Self::Folder {
196	0	UpdateFolder {
197	0	base: self.base.into_folder(),
198	0	update_op: self.update_op,
199	0	}
200	0	}
201
202	0	fn full(&self) -> bool {
203	0	self.base.full()
204	0	}
205		}
206
207		impl<'f, T, C, F> UnindexedConsumer<T> for UpdateConsumer<'f, C, F>
208		where
209		C: UnindexedConsumer<T>,
210		F: Fn(&mut T) + Send + Sync,
211		{
212	0	fn split_off_left(&self) -> Self {
213	0	UpdateConsumer::new(self.base.split_off_left(), self.update_op)
214	0	}
215
216	0	fn to_reducer(&self) -> Self::Reducer {
217	0	self.base.to_reducer()
218	0	}
219		}
220
221		struct UpdateFolder<'f, C, F> {
222		base: C,
223		update_op: &'f F,
224		}
225
226	0	fn apply<T>(update_op: impl Fn(&mut T)) -> impl Fn(T) -> T {
227	0	move \|mut item\| {
228	0	update_op(&mut item);
229	0	item
230	0	}
231	0	}
232
233		impl<'f, T, C, F> Folder<T> for UpdateFolder<'f, C, F>
234		where
235		C: Folder<T>,
236		F: Fn(&mut T),
237		{
238		type Result = C::Result;
239
240	0	fn consume(self, mut item: T) -> Self {
241	0	(self.update_op)(&mut item);
242	0
243	0	UpdateFolder {
244	0	base: self.base.consume(item),
245	0	update_op: self.update_op,
246	0	}
247	0	}
248
249	0	fn consume_iter<I>(mut self, iter: I) -> Self
250	0	where
251	0	I: IntoIterator<Item = T>,
252	0	{
253	0	let update_op = self.update_op;
254	0	self.base = self
255	0	.base
256	0	.consume_iter(iter.into_iter().map(apply(update_op)));
257	0	self
258	0	}
259
260	0	fn complete(self) -> C::Result {
261	0	self.base.complete()
262	0	}
263
264	0	fn full(&self) -> bool {
265	0	self.base.full()
266	0	}
267		}
268
269		/// Standard Update adaptor, based on `itertools::adaptors::Update`
270		#[must_use = "iterator adaptors are lazy and do nothing unless consumed"]
271		#[derive(Debug, Clone)]
272		struct UpdateSeq<I, F> {
273		base: I,
274		update_op: F,
275		}
276
277		impl<I, F> Iterator for UpdateSeq<I, F>
278		where
279		I: Iterator,
280		F: Fn(&mut I::Item),
281		{
282		type Item = I::Item;
283
284	0	fn next(&mut self) -> Option<Self::Item> {
285	0	let mut v = self.base.next()?;
286	0	(self.update_op)(&mut v);
287	0	Some(v)
288	0	}
289
290	0	fn size_hint(&self) -> (usize, Option<usize>) {
291	0	self.base.size_hint()
292	0	}
293
294	0	fn fold<Acc, G>(self, init: Acc, g: G) -> Acc
295	0	where
296	0	G: FnMut(Acc, Self::Item) -> Acc,
297	0	{
298	0	self.base.map(apply(self.update_op)).fold(init, g)
299	0	}
300
301		// if possible, re-use inner iterator specializations in collect
302	0	fn collect<C>(self) -> C
303	0	where
304	0	C: ::std::iter::FromIterator<Self::Item>,
305	0	{
306	0	self.base.map(apply(self.update_op)).collect()
307	0	}
308		}
309
310		impl<I, F> ExactSizeIterator for UpdateSeq<I, F>
311		where
312		I: ExactSizeIterator,
313		F: Fn(&mut I::Item),
314		{
315		}
316
317		impl<I, F> DoubleEndedIterator for UpdateSeq<I, F>
318		where
319		I: DoubleEndedIterator,
320		F: Fn(&mut I::Item),
321		{
322	0	fn next_back(&mut self) -> Option<Self::Item> {
323	0	let mut v = self.base.next_back()?;
324	0	(self.update_op)(&mut v);
325	0	Some(v)
326	0	}
327		}