diff options
Diffstat (limited to 'library/core/tests/iter/adapters/array_chunks.rs')
-rw-r--r-- | library/core/tests/iter/adapters/array_chunks.rs | 179 |
1 files changed, 179 insertions, 0 deletions
diff --git a/library/core/tests/iter/adapters/array_chunks.rs b/library/core/tests/iter/adapters/array_chunks.rs new file mode 100644 index 000000000..4e9d89e1e --- /dev/null +++ b/library/core/tests/iter/adapters/array_chunks.rs @@ -0,0 +1,179 @@ +use core::cell::Cell; +use core::iter::{self, Iterator}; + +use super::*; + +#[test] +fn test_iterator_array_chunks_infer() { + let xs = [1, 1, 2, -2, 6, 0, 3, 1]; + for [a, b, c] in xs.iter().copied().array_chunks() { + assert_eq!(a + b + c, 4); + } +} + +#[test] +fn test_iterator_array_chunks_clone_and_drop() { + let count = Cell::new(0); + let mut it = (0..5).map(|_| CountDrop::new(&count)).array_chunks::<3>(); + assert_eq!(it.by_ref().count(), 1); + assert_eq!(count.get(), 3); + let mut it2 = it.clone(); + assert_eq!(count.get(), 3); + assert_eq!(it.into_remainder().unwrap().len(), 2); + assert_eq!(count.get(), 5); + assert!(it2.next().is_none()); + assert_eq!(it2.into_remainder().unwrap().len(), 2); + assert_eq!(count.get(), 7); +} + +#[test] +fn test_iterator_array_chunks_remainder() { + let mut it = (0..11).array_chunks::<4>(); + assert_eq!(it.next(), Some([0, 1, 2, 3])); + assert_eq!(it.next(), Some([4, 5, 6, 7])); + assert_eq!(it.next(), None); + assert_eq!(it.into_remainder().unwrap().as_slice(), &[8, 9, 10]); +} + +#[test] +fn test_iterator_array_chunks_size_hint() { + let it = (0..6).array_chunks::<1>(); + assert_eq!(it.size_hint(), (6, Some(6))); + + let it = (0..6).array_chunks::<3>(); + assert_eq!(it.size_hint(), (2, Some(2))); + + let it = (0..6).array_chunks::<5>(); + assert_eq!(it.size_hint(), (1, Some(1))); + + let it = (0..6).array_chunks::<7>(); + assert_eq!(it.size_hint(), (0, Some(0))); + + let it = (1..).array_chunks::<2>(); + assert_eq!(it.size_hint(), (usize::MAX / 2, None)); + + let it = (1..).filter(|x| x % 2 != 0).array_chunks::<2>(); + assert_eq!(it.size_hint(), (0, None)); +} + +#[test] +fn test_iterator_array_chunks_count() { + let it = (0..6).array_chunks::<1>(); + assert_eq!(it.count(), 6); + + let it = (0..6).array_chunks::<3>(); + assert_eq!(it.count(), 2); + + let it = (0..6).array_chunks::<5>(); + assert_eq!(it.count(), 1); + + let it = (0..6).array_chunks::<7>(); + assert_eq!(it.count(), 0); + + let it = (0..6).filter(|x| x % 2 == 0).array_chunks::<2>(); + assert_eq!(it.count(), 1); + + let it = iter::empty::<i32>().array_chunks::<2>(); + assert_eq!(it.count(), 0); + + let it = [(); usize::MAX].iter().array_chunks::<2>(); + assert_eq!(it.count(), usize::MAX / 2); +} + +#[test] +fn test_iterator_array_chunks_next_and_next_back() { + let mut it = (0..11).array_chunks::<3>(); + assert_eq!(it.next(), Some([0, 1, 2])); + assert_eq!(it.next_back(), Some([6, 7, 8])); + assert_eq!(it.next(), Some([3, 4, 5])); + assert_eq!(it.next_back(), None); + assert_eq!(it.next(), None); + assert_eq!(it.next_back(), None); + assert_eq!(it.next(), None); + assert_eq!(it.into_remainder().unwrap().as_slice(), &[9, 10]); +} + +#[test] +fn test_iterator_array_chunks_rev_remainder() { + let mut it = (0..11).array_chunks::<4>(); + { + let mut it = it.by_ref().rev(); + assert_eq!(it.next(), Some([4, 5, 6, 7])); + assert_eq!(it.next(), Some([0, 1, 2, 3])); + assert_eq!(it.next(), None); + assert_eq!(it.next(), None); + } + assert_eq!(it.into_remainder().unwrap().as_slice(), &[8, 9, 10]); +} + +#[test] +fn test_iterator_array_chunks_try_fold() { + let count = Cell::new(0); + let mut it = (0..10).map(|_| CountDrop::new(&count)).array_chunks::<3>(); + let result: Result<_, ()> = it.by_ref().try_fold(0, |acc, _item| Ok(acc + 1)); + assert_eq!(result, Ok(3)); + assert_eq!(count.get(), 9); + drop(it); + assert_eq!(count.get(), 10); + + let count = Cell::new(0); + let mut it = (0..10).map(|_| CountDrop::new(&count)).array_chunks::<3>(); + let result = it.by_ref().try_fold(0, |acc, _item| if acc < 2 { Ok(acc + 1) } else { Err(acc) }); + assert_eq!(result, Err(2)); + assert_eq!(count.get(), 9); + drop(it); + assert_eq!(count.get(), 9); +} + +#[test] +fn test_iterator_array_chunks_fold() { + let result = (1..11).array_chunks::<3>().fold(0, |acc, [a, b, c]| { + assert_eq!(acc + 1, a); + assert_eq!(acc + 2, b); + assert_eq!(acc + 3, c); + acc + 3 + }); + assert_eq!(result, 9); + + let count = Cell::new(0); + let result = + (0..10).map(|_| CountDrop::new(&count)).array_chunks::<3>().fold(0, |acc, _item| acc + 1); + assert_eq!(result, 3); + assert_eq!(count.get(), 10); +} + +#[test] +fn test_iterator_array_chunks_try_rfold() { + let count = Cell::new(0); + let mut it = (0..10).map(|_| CountDrop::new(&count)).array_chunks::<3>(); + let result: Result<_, ()> = it.try_rfold(0, |acc, _item| Ok(acc + 1)); + assert_eq!(result, Ok(3)); + assert_eq!(count.get(), 9); + drop(it); + assert_eq!(count.get(), 10); + + let count = Cell::new(0); + let mut it = (0..10).map(|_| CountDrop::new(&count)).array_chunks::<3>(); + let result = it.try_rfold(0, |acc, _item| if acc < 2 { Ok(acc + 1) } else { Err(acc) }); + assert_eq!(result, Err(2)); + assert_eq!(count.get(), 9); + drop(it); + assert_eq!(count.get(), 10); +} + +#[test] +fn test_iterator_array_chunks_rfold() { + let result = (1..11).array_chunks::<3>().rfold(0, |acc, [a, b, c]| { + assert_eq!(10 - (acc + 1), c); + assert_eq!(10 - (acc + 2), b); + assert_eq!(10 - (acc + 3), a); + acc + 3 + }); + assert_eq!(result, 9); + + let count = Cell::new(0); + let result = + (0..10).map(|_| CountDrop::new(&count)).array_chunks::<3>().rfold(0, |acc, _item| acc + 1); + assert_eq!(result, 3); + assert_eq!(count.get(), 10); +} |