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Diffstat (limited to 'vendor/rayon/src/iter/fold_chunks.rs')
| -rw-r--r-- | vendor/rayon/src/iter/fold_chunks.rs | 236 |
1 files changed, 0 insertions, 236 deletions
diff --git a/vendor/rayon/src/iter/fold_chunks.rs b/vendor/rayon/src/iter/fold_chunks.rs deleted file mode 100644 index 185fb1a..0000000 --- a/vendor/rayon/src/iter/fold_chunks.rs +++ /dev/null @@ -1,236 +0,0 @@ -use std::fmt::{self, Debug}; - -use super::chunks::ChunkProducer; -use super::plumbing::*; -use super::*; -use crate::math::div_round_up; - -/// `FoldChunks` is an iterator that groups elements of an underlying iterator and applies a -/// function over them, producing a single value for each group. -/// -/// This struct is created by the [`fold_chunks()`] method on [`IndexedParallelIterator`] -/// -/// [`fold_chunks()`]: trait.IndexedParallelIterator.html#method.fold_chunks -/// [`IndexedParallelIterator`]: trait.IndexedParallelIterator.html -#[must_use = "iterator adaptors are lazy and do nothing unless consumed"] -#[derive(Clone)] -pub struct FoldChunks<I, ID, F> -where - I: IndexedParallelIterator, -{ - base: I, - chunk_size: usize, - fold_op: F, - identity: ID, -} - -impl<I: IndexedParallelIterator + Debug, ID, F> Debug for FoldChunks<I, ID, F> { - fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { - f.debug_struct("Fold") - .field("base", &self.base) - .field("chunk_size", &self.chunk_size) - .finish() - } -} - -impl<I, ID, U, F> FoldChunks<I, ID, F> -where - I: IndexedParallelIterator, - ID: Fn() -> U + Send + Sync, - F: Fn(U, I::Item) -> U + Send + Sync, - U: Send, -{ - /// Creates a new `FoldChunks` iterator - pub(super) fn new(base: I, chunk_size: usize, identity: ID, fold_op: F) -> Self { - FoldChunks { - base, - chunk_size, - identity, - fold_op, - } - } -} - -impl<I, ID, U, F> ParallelIterator for FoldChunks<I, ID, F> -where - I: IndexedParallelIterator, - ID: Fn() -> U + Send + Sync, - F: Fn(U, I::Item) -> U + Send + Sync, - U: Send, -{ - type Item = U; - - fn drive_unindexed<C>(self, consumer: C) -> C::Result - where - C: Consumer<U>, - { - bridge(self, consumer) - } - - fn opt_len(&self) -> Option<usize> { - Some(self.len()) - } -} - -impl<I, ID, U, F> IndexedParallelIterator for FoldChunks<I, ID, F> -where - I: IndexedParallelIterator, - ID: Fn() -> U + Send + Sync, - F: Fn(U, I::Item) -> U + Send + Sync, - U: Send, -{ - fn len(&self) -> usize { - div_round_up(self.base.len(), self.chunk_size) - } - - fn drive<C>(self, consumer: C) -> C::Result - where - C: Consumer<Self::Item>, - { - bridge(self, consumer) - } - - fn with_producer<CB>(self, callback: CB) -> CB::Output - where - CB: ProducerCallback<Self::Item>, - { - let len = self.base.len(); - return self.base.with_producer(Callback { - chunk_size: self.chunk_size, - len, - identity: self.identity, - fold_op: self.fold_op, - callback, - }); - - struct Callback<CB, ID, F> { - chunk_size: usize, - len: usize, - identity: ID, - fold_op: F, - callback: CB, - } - - impl<T, CB, ID, U, F> ProducerCallback<T> for Callback<CB, ID, F> - where - CB: ProducerCallback<U>, - ID: Fn() -> U + Send + Sync, - F: Fn(U, T) -> U + Send + Sync, - { - type Output = CB::Output; - - fn callback<P>(self, base: P) -> CB::Output - where - P: Producer<Item = T>, - { - let identity = &self.identity; - let fold_op = &self.fold_op; - let fold_iter = move |iter: P::IntoIter| iter.fold(identity(), fold_op); - let producer = ChunkProducer::new(self.chunk_size, self.len, base, fold_iter); - self.callback.callback(producer) - } - } - } -} - -#[cfg(test)] -mod test { - use super::*; - use std::ops::Add; - - #[test] - fn check_fold_chunks() { - let words = "bishbashbosh!" - .chars() - .collect::<Vec<_>>() - .into_par_iter() - .fold_chunks(4, String::new, |mut s, c| { - s.push(c); - s - }) - .collect::<Vec<_>>(); - - assert_eq!(words, vec!["bish", "bash", "bosh", "!"]); - } - - // 'closure' values for tests below - fn id() -> i32 { - 0 - } - fn sum<T, U>(x: T, y: U) -> T - where - T: Add<U, Output = T>, - { - x + y - } - - #[test] - #[should_panic(expected = "chunk_size must not be zero")] - fn check_fold_chunks_zero_size() { - let _: Vec<i32> = vec![1, 2, 3] - .into_par_iter() - .fold_chunks(0, id, sum) - .collect(); - } - - #[test] - fn check_fold_chunks_even_size() { - assert_eq!( - vec![1 + 2 + 3, 4 + 5 + 6, 7 + 8 + 9], - (1..10) - .into_par_iter() - .fold_chunks(3, id, sum) - .collect::<Vec<i32>>() - ); - } - - #[test] - fn check_fold_chunks_empty() { - let v: Vec<i32> = vec![]; - let expected: Vec<i32> = vec![]; - assert_eq!( - expected, - v.into_par_iter() - .fold_chunks(2, id, sum) - .collect::<Vec<i32>>() - ); - } - - #[test] - fn check_fold_chunks_len() { - assert_eq!(4, (0..8).into_par_iter().fold_chunks(2, id, sum).len()); - assert_eq!(3, (0..9).into_par_iter().fold_chunks(3, id, sum).len()); - assert_eq!(3, (0..8).into_par_iter().fold_chunks(3, id, sum).len()); - assert_eq!(1, (&[1]).par_iter().fold_chunks(3, id, sum).len()); - assert_eq!(0, (0..0).into_par_iter().fold_chunks(3, id, sum).len()); - } - - #[test] - fn check_fold_chunks_uneven() { - let cases: Vec<(Vec<u32>, usize, Vec<u32>)> = vec![ - ((0..5).collect(), 3, vec![0 + 1 + 2, 3 + 4]), - (vec![1], 5, vec![1]), - ((0..4).collect(), 3, vec![0 + 1 + 2, 3]), - ]; - - for (i, (v, n, expected)) in cases.into_iter().enumerate() { - let mut res: Vec<u32> = vec![]; - v.par_iter() - .fold_chunks(n, || 0, sum) - .collect_into_vec(&mut res); - assert_eq!(expected, res, "Case {} failed", i); - - res.truncate(0); - v.into_par_iter() - .fold_chunks(n, || 0, sum) - .rev() - .collect_into_vec(&mut res); - assert_eq!( - expected.into_iter().rev().collect::<Vec<u32>>(), - res, - "Case {} reversed failed", - i - ); - } - } -} |