use core::cell::Cell; use core::cmp::Ordering; use core::mem::MaybeUninit; use core::result::Result::{Err, Ok}; use core::slice; #[test] fn test_position() { let b = [1, 2, 3, 5, 5]; assert_eq!(b.iter().position(|&v| v == 9), None); assert_eq!(b.iter().position(|&v| v == 5), Some(3)); assert_eq!(b.iter().position(|&v| v == 3), Some(2)); assert_eq!(b.iter().position(|&v| v == 0), None); } #[test] fn test_rposition() { let b = [1, 2, 3, 5, 5]; assert_eq!(b.iter().rposition(|&v| v == 9), None); assert_eq!(b.iter().rposition(|&v| v == 5), Some(4)); assert_eq!(b.iter().rposition(|&v| v == 3), Some(2)); assert_eq!(b.iter().rposition(|&v| v == 0), None); } #[test] fn test_binary_search() { let b: [i32; 0] = []; assert_eq!(b.binary_search(&5), Err(0)); let b = [4]; assert_eq!(b.binary_search(&3), Err(0)); assert_eq!(b.binary_search(&4), Ok(0)); assert_eq!(b.binary_search(&5), Err(1)); let b = [1, 2, 4, 6, 8, 9]; assert_eq!(b.binary_search(&5), Err(3)); assert_eq!(b.binary_search(&6), Ok(3)); assert_eq!(b.binary_search(&7), Err(4)); assert_eq!(b.binary_search(&8), Ok(4)); let b = [1, 2, 4, 5, 6, 8]; assert_eq!(b.binary_search(&9), Err(6)); let b = [1, 2, 4, 6, 7, 8, 9]; assert_eq!(b.binary_search(&6), Ok(3)); assert_eq!(b.binary_search(&5), Err(3)); assert_eq!(b.binary_search(&8), Ok(5)); let b = [1, 2, 4, 5, 6, 8, 9]; assert_eq!(b.binary_search(&7), Err(5)); assert_eq!(b.binary_search(&0), Err(0)); let b = [1, 3, 3, 3, 7]; assert_eq!(b.binary_search(&0), Err(0)); assert_eq!(b.binary_search(&1), Ok(0)); assert_eq!(b.binary_search(&2), Err(1)); assert!(match b.binary_search(&3) { Ok(1..=3) => true, _ => false, }); assert!(match b.binary_search(&3) { Ok(1..=3) => true, _ => false, }); assert_eq!(b.binary_search(&4), Err(4)); assert_eq!(b.binary_search(&5), Err(4)); assert_eq!(b.binary_search(&6), Err(4)); assert_eq!(b.binary_search(&7), Ok(4)); assert_eq!(b.binary_search(&8), Err(5)); let b = [(); usize::MAX]; assert_eq!(b.binary_search(&()), Ok(usize::MAX / 2)); } #[test] fn test_binary_search_by_overflow() { let b = [(); usize::MAX]; assert_eq!(b.binary_search_by(|_| Ordering::Equal), Ok(usize::MAX / 2)); assert_eq!(b.binary_search_by(|_| Ordering::Greater), Err(0)); assert_eq!(b.binary_search_by(|_| Ordering::Less), Err(usize::MAX)); } #[test] // Test implementation specific behavior when finding equivalent elements. // It is ok to break this test but when you do a crater run is highly advisable. fn test_binary_search_implementation_details() { let b = [1, 1, 2, 2, 3, 3, 3]; assert_eq!(b.binary_search(&1), Ok(1)); assert_eq!(b.binary_search(&2), Ok(3)); assert_eq!(b.binary_search(&3), Ok(5)); let b = [1, 1, 1, 1, 1, 3, 3, 3, 3]; assert_eq!(b.binary_search(&1), Ok(4)); assert_eq!(b.binary_search(&3), Ok(7)); let b = [1, 1, 1, 1, 3, 3, 3, 3, 3]; assert_eq!(b.binary_search(&1), Ok(2)); assert_eq!(b.binary_search(&3), Ok(4)); } #[test] fn test_partition_point() { let b: [i32; 0] = []; assert_eq!(b.partition_point(|&x| x < 5), 0); let b = [4]; assert_eq!(b.partition_point(|&x| x < 3), 0); assert_eq!(b.partition_point(|&x| x < 4), 0); assert_eq!(b.partition_point(|&x| x < 5), 1); let b = [1, 2, 4, 6, 8, 9]; assert_eq!(b.partition_point(|&x| x < 5), 3); assert_eq!(b.partition_point(|&x| x < 6), 3); assert_eq!(b.partition_point(|&x| x < 7), 4); assert_eq!(b.partition_point(|&x| x < 8), 4); let b = [1, 2, 4, 5, 6, 8]; assert_eq!(b.partition_point(|&x| x < 9), 6); let b = [1, 2, 4, 6, 7, 8, 9]; assert_eq!(b.partition_point(|&x| x < 6), 3); assert_eq!(b.partition_point(|&x| x < 5), 3); assert_eq!(b.partition_point(|&x| x < 8), 5); let b = [1, 2, 4, 5, 6, 8, 9]; assert_eq!(b.partition_point(|&x| x < 7), 5); assert_eq!(b.partition_point(|&x| x < 0), 0); let b = [1, 3, 3, 3, 7]; assert_eq!(b.partition_point(|&x| x < 0), 0); assert_eq!(b.partition_point(|&x| x < 1), 0); assert_eq!(b.partition_point(|&x| x < 2), 1); assert_eq!(b.partition_point(|&x| x < 3), 1); assert_eq!(b.partition_point(|&x| x < 4), 4); assert_eq!(b.partition_point(|&x| x < 5), 4); assert_eq!(b.partition_point(|&x| x < 6), 4); assert_eq!(b.partition_point(|&x| x < 7), 4); assert_eq!(b.partition_point(|&x| x < 8), 5); } #[test] fn test_iterator_advance_by() { let v = &[0, 1, 2, 3, 4]; for i in 0..=v.len() { let mut iter = v.iter(); iter.advance_by(i).unwrap(); assert_eq!(iter.as_slice(), &v[i..]); } let mut iter = v.iter(); assert_eq!(iter.advance_by(v.len() + 1), Err(v.len())); assert_eq!(iter.as_slice(), &[]); let mut iter = v.iter(); iter.advance_by(3).unwrap(); assert_eq!(iter.as_slice(), &v[3..]); iter.advance_by(2).unwrap(); assert_eq!(iter.as_slice(), &[]); iter.advance_by(0).unwrap(); } #[test] fn test_iterator_advance_back_by() { let v = &[0, 1, 2, 3, 4]; for i in 0..=v.len() { let mut iter = v.iter(); iter.advance_back_by(i).unwrap(); assert_eq!(iter.as_slice(), &v[..v.len() - i]); } let mut iter = v.iter(); assert_eq!(iter.advance_back_by(v.len() + 1), Err(v.len())); assert_eq!(iter.as_slice(), &[]); let mut iter = v.iter(); iter.advance_back_by(3).unwrap(); assert_eq!(iter.as_slice(), &v[..v.len() - 3]); iter.advance_back_by(2).unwrap(); assert_eq!(iter.as_slice(), &[]); iter.advance_back_by(0).unwrap(); } #[test] fn test_iterator_nth() { let v: &[_] = &[0, 1, 2, 3, 4]; for i in 0..v.len() { assert_eq!(v.iter().nth(i).unwrap(), &v[i]); } assert_eq!(v.iter().nth(v.len()), None); let mut iter = v.iter(); assert_eq!(iter.nth(2).unwrap(), &v[2]); assert_eq!(iter.nth(1).unwrap(), &v[4]); } #[test] fn test_iterator_nth_back() { let v: &[_] = &[0, 1, 2, 3, 4]; for i in 0..v.len() { assert_eq!(v.iter().nth_back(i).unwrap(), &v[v.len() - i - 1]); } assert_eq!(v.iter().nth_back(v.len()), None); let mut iter = v.iter(); assert_eq!(iter.nth_back(2).unwrap(), &v[2]); assert_eq!(iter.nth_back(1).unwrap(), &v[0]); } #[test] fn test_iterator_last() { let v: &[_] = &[0, 1, 2, 3, 4]; assert_eq!(v.iter().last().unwrap(), &4); assert_eq!(v[..1].iter().last().unwrap(), &0); } #[test] fn test_iterator_count() { let v: &[_] = &[0, 1, 2, 3, 4]; assert_eq!(v.iter().count(), 5); let mut iter2 = v.iter(); iter2.next(); iter2.next(); assert_eq!(iter2.count(), 3); } #[test] fn test_chunks_count() { let v: &[i32] = &[0, 1, 2, 3, 4, 5]; let c = v.chunks(3); assert_eq!(c.count(), 2); let v2: &[i32] = &[0, 1, 2, 3, 4]; let c2 = v2.chunks(2); assert_eq!(c2.count(), 3); let v3: &[i32] = &[]; let c3 = v3.chunks(2); assert_eq!(c3.count(), 0); } #[test] fn test_chunks_nth() { let v: &[i32] = &[0, 1, 2, 3, 4, 5]; let mut c = v.chunks(2); assert_eq!(c.nth(1).unwrap(), &[2, 3]); assert_eq!(c.next().unwrap(), &[4, 5]); let v2: &[i32] = &[0, 1, 2, 3, 4]; let mut c2 = v2.chunks(3); assert_eq!(c2.nth(1).unwrap(), &[3, 4]); assert_eq!(c2.next(), None); } #[test] fn test_chunks_next() { let v = [0, 1, 2, 3, 4, 5]; let mut c = v.chunks(2); assert_eq!(c.next().unwrap(), &[0, 1]); assert_eq!(c.next().unwrap(), &[2, 3]); assert_eq!(c.next().unwrap(), &[4, 5]); assert_eq!(c.next(), None); let v = [0, 1, 2, 3, 4, 5, 6, 7]; let mut c = v.chunks(3); assert_eq!(c.next().unwrap(), &[0, 1, 2]); assert_eq!(c.next().unwrap(), &[3, 4, 5]); assert_eq!(c.next().unwrap(), &[6, 7]); assert_eq!(c.next(), None); } #[test] fn test_chunks_next_back() { let v = [0, 1, 2, 3, 4, 5]; let mut c = v.chunks(2); assert_eq!(c.next_back().unwrap(), &[4, 5]); assert_eq!(c.next_back().unwrap(), &[2, 3]); assert_eq!(c.next_back().unwrap(), &[0, 1]); assert_eq!(c.next_back(), None); let v = [0, 1, 2, 3, 4, 5, 6, 7]; let mut c = v.chunks(3); assert_eq!(c.next_back().unwrap(), &[6, 7]); assert_eq!(c.next_back().unwrap(), &[3, 4, 5]); assert_eq!(c.next_back().unwrap(), &[0, 1, 2]); assert_eq!(c.next_back(), None); } #[test] fn test_chunks_nth_back() { let v: &[i32] = &[0, 1, 2, 3, 4, 5]; let mut c = v.chunks(2); assert_eq!(c.nth_back(1).unwrap(), &[2, 3]); assert_eq!(c.next().unwrap(), &[0, 1]); assert_eq!(c.next(), None); let v2: &[i32] = &[0, 1, 2, 3, 4]; let mut c2 = v2.chunks(3); assert_eq!(c2.nth_back(1).unwrap(), &[0, 1, 2]); assert_eq!(c2.next(), None); assert_eq!(c2.next_back(), None); let v3: &[i32] = &[0, 1, 2, 3, 4]; let mut c3 = v3.chunks(10); assert_eq!(c3.nth_back(0).unwrap(), &[0, 1, 2, 3, 4]); assert_eq!(c3.next(), None); let v4: &[i32] = &[0, 1, 2]; let mut c4 = v4.chunks(10); assert_eq!(c4.nth_back(1_000_000_000usize), None); } #[test] fn test_chunks_last() { let v: &[i32] = &[0, 1, 2, 3, 4, 5]; let c = v.chunks(2); assert_eq!(c.last().unwrap()[1], 5); let v2: &[i32] = &[0, 1, 2, 3, 4]; let c2 = v2.chunks(2); assert_eq!(c2.last().unwrap()[0], 4); } #[test] fn test_chunks_zip() { let v1: &[i32] = &[0, 1, 2, 3, 4]; let v2: &[i32] = &[6, 7, 8, 9, 10]; let res = v1 .chunks(2) .zip(v2.chunks(2)) .map(|(a, b)| a.iter().sum::() + b.iter().sum::()) .collect::>(); assert_eq!(res, vec![14, 22, 14]); } #[test] fn test_chunks_mut_count() { let v: &mut [i32] = &mut [0, 1, 2, 3, 4, 5]; let c = v.chunks_mut(3); assert_eq!(c.count(), 2); let v2: &mut [i32] = &mut [0, 1, 2, 3, 4]; let c2 = v2.chunks_mut(2); assert_eq!(c2.count(), 3); let v3: &mut [i32] = &mut []; let c3 = v3.chunks_mut(2); assert_eq!(c3.count(), 0); } #[test] fn test_chunks_mut_nth() { let v: &mut [i32] = &mut [0, 1, 2, 3, 4, 5]; let mut c = v.chunks_mut(2); assert_eq!(c.nth(1).unwrap(), &[2, 3]); assert_eq!(c.next().unwrap(), &[4, 5]); let v2: &mut [i32] = &mut [0, 1, 2, 3, 4]; let mut c2 = v2.chunks_mut(3); assert_eq!(c2.nth(1).unwrap(), &[3, 4]); assert_eq!(c2.next(), None); } #[test] fn test_chunks_mut_nth_back() { let v: &mut [i32] = &mut [0, 1, 2, 3, 4, 5]; let mut c = v.chunks_mut(2); assert_eq!(c.nth_back(1).unwrap(), &[2, 3]); assert_eq!(c.next().unwrap(), &[0, 1]); let v1: &mut [i32] = &mut [0, 1, 2, 3, 4]; let mut c1 = v1.chunks_mut(3); assert_eq!(c1.nth_back(1).unwrap(), &[0, 1, 2]); assert_eq!(c1.next(), None); let v3: &mut [i32] = &mut [0, 1, 2, 3, 4]; let mut c3 = v3.chunks_mut(10); assert_eq!(c3.nth_back(0).unwrap(), &[0, 1, 2, 3, 4]); assert_eq!(c3.next(), None); let v4: &mut [i32] = &mut [0, 1, 2]; let mut c4 = v4.chunks_mut(10); assert_eq!(c4.nth_back(1_000_000_000usize), None); } #[test] fn test_chunks_mut_last() { let v: &mut [i32] = &mut [0, 1, 2, 3, 4, 5]; let c = v.chunks_mut(2); assert_eq!(c.last().unwrap(), &[4, 5]); let v2: &mut [i32] = &mut [0, 1, 2, 3, 4]; let c2 = v2.chunks_mut(2); assert_eq!(c2.last().unwrap(), &[4]); } #[test] fn test_chunks_mut_zip() { let v1: &mut [i32] = &mut [0, 1, 2, 3, 4]; let v2: &[i32] = &[6, 7, 8, 9, 10]; for (a, b) in v1.chunks_mut(2).zip(v2.chunks(2)) { let sum = b.iter().sum::(); for v in a { *v += sum; } } assert_eq!(v1, [13, 14, 19, 20, 14]); } #[test] fn test_chunks_mut_zip_aliasing() { let v1: &mut [i32] = &mut [0, 1, 2, 3, 4]; let v2: &[i32] = &[6, 7, 8, 9, 10]; let mut it = v1.chunks_mut(2).zip(v2.chunks(2)); let first = it.next().unwrap(); let _ = it.next().unwrap(); assert_eq!(first, (&mut [0, 1][..], &[6, 7][..])); } #[test] fn test_chunks_exact_mut_zip_aliasing() { let v1: &mut [i32] = &mut [0, 1, 2, 3, 4]; let v2: &[i32] = &[6, 7, 8, 9, 10]; let mut it = v1.chunks_exact_mut(2).zip(v2.chunks(2)); let first = it.next().unwrap(); let _ = it.next().unwrap(); assert_eq!(first, (&mut [0, 1][..], &[6, 7][..])); } #[test] fn test_rchunks_mut_zip_aliasing() { let v1: &mut [i32] = &mut [0, 1, 2, 3, 4]; let v2: &[i32] = &[6, 7, 8, 9, 10]; let mut it = v1.rchunks_mut(2).zip(v2.chunks(2)); let first = it.next().unwrap(); let _ = it.next().unwrap(); assert_eq!(first, (&mut [3, 4][..], &[6, 7][..])); } #[test] fn test_rchunks_exact_mut_zip_aliasing() { let v1: &mut [i32] = &mut [0, 1, 2, 3, 4]; let v2: &[i32] = &[6, 7, 8, 9, 10]; let mut it = v1.rchunks_exact_mut(2).zip(v2.chunks(2)); let first = it.next().unwrap(); let _ = it.next().unwrap(); assert_eq!(first, (&mut [3, 4][..], &[6, 7][..])); } #[test] fn test_chunks_exact_count() { let v: &[i32] = &[0, 1, 2, 3, 4, 5]; let c = v.chunks_exact(3); assert_eq!(c.count(), 2); let v2: &[i32] = &[0, 1, 2, 3, 4]; let c2 = v2.chunks_exact(2); assert_eq!(c2.count(), 2); let v3: &[i32] = &[]; let c3 = v3.chunks_exact(2); assert_eq!(c3.count(), 0); } #[test] fn test_chunks_exact_nth() { let v: &[i32] = &[0, 1, 2, 3, 4, 5]; let mut c = v.chunks_exact(2); assert_eq!(c.nth(1).unwrap(), &[2, 3]); assert_eq!(c.next().unwrap(), &[4, 5]); let v2: &[i32] = &[0, 1, 2, 3, 4, 5, 6]; let mut c2 = v2.chunks_exact(3); assert_eq!(c2.nth(1).unwrap(), &[3, 4, 5]); assert_eq!(c2.next(), None); } #[test] fn test_chunks_exact_nth_back() { let v: &[i32] = &[0, 1, 2, 3, 4, 5]; let mut c = v.chunks_exact(2); assert_eq!(c.nth_back(1).unwrap(), &[2, 3]); assert_eq!(c.next().unwrap(), &[0, 1]); assert_eq!(c.next(), None); let v2: &[i32] = &[0, 1, 2, 3, 4]; let mut c2 = v2.chunks_exact(3); assert_eq!(c2.nth_back(0).unwrap(), &[0, 1, 2]); assert_eq!(c2.next(), None); assert_eq!(c2.next_back(), None); let v3: &[i32] = &[0, 1, 2, 3, 4]; let mut c3 = v3.chunks_exact(10); assert_eq!(c3.nth_back(0), None); } #[test] fn test_chunks_exact_last() { let v: &[i32] = &[0, 1, 2, 3, 4, 5]; let c = v.chunks_exact(2); assert_eq!(c.last().unwrap(), &[4, 5]); let v2: &[i32] = &[0, 1, 2, 3, 4]; let c2 = v2.chunks_exact(2); assert_eq!(c2.last().unwrap(), &[2, 3]); } #[test] fn test_chunks_exact_remainder() { let v: &[i32] = &[0, 1, 2, 3, 4]; let c = v.chunks_exact(2); assert_eq!(c.remainder(), &[4]); } #[test] fn test_chunks_exact_zip() { let v1: &[i32] = &[0, 1, 2, 3, 4]; let v2: &[i32] = &[6, 7, 8, 9, 10]; let res = v1 .chunks_exact(2) .zip(v2.chunks_exact(2)) .map(|(a, b)| a.iter().sum::() + b.iter().sum::()) .collect::>(); assert_eq!(res, vec![14, 22]); } #[test] fn test_chunks_exact_mut_count() { let v: &mut [i32] = &mut [0, 1, 2, 3, 4, 5]; let c = v.chunks_exact_mut(3); assert_eq!(c.count(), 2); let v2: &mut [i32] = &mut [0, 1, 2, 3, 4]; let c2 = v2.chunks_exact_mut(2); assert_eq!(c2.count(), 2); let v3: &mut [i32] = &mut []; let c3 = v3.chunks_exact_mut(2); assert_eq!(c3.count(), 0); } #[test] fn test_chunks_exact_mut_nth() { let v: &mut [i32] = &mut [0, 1, 2, 3, 4, 5]; let mut c = v.chunks_exact_mut(2); assert_eq!(c.nth(1).unwrap(), &[2, 3]); assert_eq!(c.next().unwrap(), &[4, 5]); let v2: &mut [i32] = &mut [0, 1, 2, 3, 4, 5, 6]; let mut c2 = v2.chunks_exact_mut(3); assert_eq!(c2.nth(1).unwrap(), &[3, 4, 5]); assert_eq!(c2.next(), None); } #[test] fn test_chunks_exact_mut_nth_back() { let v: &mut [i32] = &mut [0, 1, 2, 3, 4, 5]; let mut c = v.chunks_exact_mut(2); assert_eq!(c.nth_back(1).unwrap(), &[2, 3]); assert_eq!(c.next().unwrap(), &[0, 1]); assert_eq!(c.next(), None); let v2: &mut [i32] = &mut [0, 1, 2, 3, 4]; let mut c2 = v2.chunks_exact_mut(3); assert_eq!(c2.nth_back(0).unwrap(), &[0, 1, 2]); assert_eq!(c2.next(), None); assert_eq!(c2.next_back(), None); let v3: &mut [i32] = &mut [0, 1, 2, 3, 4]; let mut c3 = v3.chunks_exact_mut(10); assert_eq!(c3.nth_back(0), None); } #[test] fn test_chunks_exact_mut_last() { let v: &mut [i32] = &mut [0, 1, 2, 3, 4, 5]; let c = v.chunks_exact_mut(2); assert_eq!(c.last().unwrap(), &[4, 5]); let v2: &mut [i32] = &mut [0, 1, 2, 3, 4]; let c2 = v2.chunks_exact_mut(2); assert_eq!(c2.last().unwrap(), &[2, 3]); } #[test] fn test_chunks_exact_mut_remainder() { let v: &mut [i32] = &mut [0, 1, 2, 3, 4]; let c = v.chunks_exact_mut(2); assert_eq!(c.into_remainder(), &[4]); } #[test] fn test_chunks_exact_mut_zip() { let v1: &mut [i32] = &mut [0, 1, 2, 3, 4]; let v2: &[i32] = &[6, 7, 8, 9, 10]; for (a, b) in v1.chunks_exact_mut(2).zip(v2.chunks_exact(2)) { let sum = b.iter().sum::(); for v in a { *v += sum; } } assert_eq!(v1, [13, 14, 19, 20, 4]); } #[test] fn test_array_chunks_infer() { let v: &[i32] = &[0, 1, 2, 3, 4, -4]; let c = v.array_chunks(); for &[a, b, c] in c { assert_eq!(a + b + c, 3); } let v2: &[i32] = &[0, 1, 2, 3, 4, 5, 6]; let total = v2.array_chunks().map(|&[a, b]| a * b).sum::(); assert_eq!(total, 2 * 3 + 4 * 5); } #[test] fn test_array_chunks_count() { let v: &[i32] = &[0, 1, 2, 3, 4, 5]; let c = v.array_chunks::<3>(); assert_eq!(c.count(), 2); let v2: &[i32] = &[0, 1, 2, 3, 4]; let c2 = v2.array_chunks::<2>(); assert_eq!(c2.count(), 2); let v3: &[i32] = &[]; let c3 = v3.array_chunks::<2>(); assert_eq!(c3.count(), 0); } #[test] fn test_array_chunks_nth() { let v: &[i32] = &[0, 1, 2, 3, 4, 5]; let mut c = v.array_chunks::<2>(); assert_eq!(c.nth(1).unwrap(), &[2, 3]); assert_eq!(c.next().unwrap(), &[4, 5]); let v2: &[i32] = &[0, 1, 2, 3, 4, 5, 6]; let mut c2 = v2.array_chunks::<3>(); assert_eq!(c2.nth(1).unwrap(), &[3, 4, 5]); assert_eq!(c2.next(), None); } #[test] fn test_array_chunks_nth_back() { let v: &[i32] = &[0, 1, 2, 3, 4, 5]; let mut c = v.array_chunks::<2>(); assert_eq!(c.nth_back(1).unwrap(), &[2, 3]); assert_eq!(c.next().unwrap(), &[0, 1]); assert_eq!(c.next(), None); let v2: &[i32] = &[0, 1, 2, 3, 4]; let mut c2 = v2.array_chunks::<3>(); assert_eq!(c2.nth_back(0).unwrap(), &[0, 1, 2]); assert_eq!(c2.next(), None); assert_eq!(c2.next_back(), None); let v3: &[i32] = &[0, 1, 2, 3, 4]; let mut c3 = v3.array_chunks::<10>(); assert_eq!(c3.nth_back(0), None); } #[test] fn test_array_chunks_last() { let v: &[i32] = &[0, 1, 2, 3, 4, 5]; let c = v.array_chunks::<2>(); assert_eq!(c.last().unwrap(), &[4, 5]); let v2: &[i32] = &[0, 1, 2, 3, 4]; let c2 = v2.array_chunks::<2>(); assert_eq!(c2.last().unwrap(), &[2, 3]); } #[test] fn test_array_chunks_remainder() { let v: &[i32] = &[0, 1, 2, 3, 4]; let c = v.array_chunks::<2>(); assert_eq!(c.remainder(), &[4]); } #[test] fn test_array_chunks_zip() { let v1: &[i32] = &[0, 1, 2, 3, 4]; let v2: &[i32] = &[6, 7, 8, 9, 10]; let res = v1 .array_chunks::<2>() .zip(v2.array_chunks::<2>()) .map(|(a, b)| a.iter().sum::() + b.iter().sum::()) .collect::>(); assert_eq!(res, vec![14, 22]); } #[test] fn test_array_chunks_mut_infer() { let v: &mut [i32] = &mut [0, 1, 2, 3, 4, 5, 6]; for a in v.array_chunks_mut() { let sum = a.iter().sum::(); *a = [sum; 3]; } assert_eq!(v, &[3, 3, 3, 12, 12, 12, 6]); let v2: &mut [i32] = &mut [0, 1, 2, 3, 4, 5, 6]; v2.array_chunks_mut().for_each(|[a, b]| core::mem::swap(a, b)); assert_eq!(v2, &[1, 0, 3, 2, 5, 4, 6]); } #[test] fn test_array_chunks_mut_count() { let v: &mut [i32] = &mut [0, 1, 2, 3, 4, 5]; let c = v.array_chunks_mut::<3>(); assert_eq!(c.count(), 2); let v2: &mut [i32] = &mut [0, 1, 2, 3, 4]; let c2 = v2.array_chunks_mut::<2>(); assert_eq!(c2.count(), 2); let v3: &mut [i32] = &mut []; let c3 = v3.array_chunks_mut::<2>(); assert_eq!(c3.count(), 0); } #[test] fn test_array_chunks_mut_nth() { let v: &mut [i32] = &mut [0, 1, 2, 3, 4, 5]; let mut c = v.array_chunks_mut::<2>(); assert_eq!(c.nth(1).unwrap(), &[2, 3]); assert_eq!(c.next().unwrap(), &[4, 5]); let v2: &mut [i32] = &mut [0, 1, 2, 3, 4, 5, 6]; let mut c2 = v2.array_chunks_mut::<3>(); assert_eq!(c2.nth(1).unwrap(), &[3, 4, 5]); assert_eq!(c2.next(), None); } #[test] fn test_array_chunks_mut_nth_back() { let v: &mut [i32] = &mut [0, 1, 2, 3, 4, 5]; let mut c = v.array_chunks_mut::<2>(); assert_eq!(c.nth_back(1).unwrap(), &[2, 3]); assert_eq!(c.next().unwrap(), &[0, 1]); assert_eq!(c.next(), None); let v2: &mut [i32] = &mut [0, 1, 2, 3, 4]; let mut c2 = v2.array_chunks_mut::<3>(); assert_eq!(c2.nth_back(0).unwrap(), &[0, 1, 2]); assert_eq!(c2.next(), None); assert_eq!(c2.next_back(), None); let v3: &mut [i32] = &mut [0, 1, 2, 3, 4]; let mut c3 = v3.array_chunks_mut::<10>(); assert_eq!(c3.nth_back(0), None); } #[test] fn test_array_chunks_mut_last() { let v: &mut [i32] = &mut [0, 1, 2, 3, 4, 5]; let c = v.array_chunks_mut::<2>(); assert_eq!(c.last().unwrap(), &[4, 5]); let v2: &mut [i32] = &mut [0, 1, 2, 3, 4]; let c2 = v2.array_chunks_mut::<2>(); assert_eq!(c2.last().unwrap(), &[2, 3]); } #[test] fn test_array_chunks_mut_remainder() { let v: &mut [i32] = &mut [0, 1, 2, 3, 4]; let c = v.array_chunks_mut::<2>(); assert_eq!(c.into_remainder(), &[4]); } #[test] fn test_array_chunks_mut_zip() { let v1: &mut [i32] = &mut [0, 1, 2, 3, 4]; let v2: &[i32] = &[6, 7, 8, 9, 10]; for (a, b) in v1.array_chunks_mut::<2>().zip(v2.array_chunks::<2>()) { let sum = b.iter().sum::(); for v in a { *v += sum; } } assert_eq!(v1, [13, 14, 19, 20, 4]); } #[test] fn test_array_windows_infer() { let v: &[i32] = &[0, 1, 0, 1]; assert_eq!(v.array_windows::<2>().count(), 3); let c = v.array_windows(); for &[a, b] in c { assert_eq!(a + b, 1); } let v2: &[i32] = &[0, 1, 2, 3, 4, 5, 6]; let total = v2.array_windows().map(|&[a, b, c]| a + b + c).sum::(); assert_eq!(total, 3 + 6 + 9 + 12 + 15); } #[test] fn test_array_windows_count() { let v: &[i32] = &[0, 1, 2, 3, 4, 5]; let c = v.array_windows::<3>(); assert_eq!(c.count(), 4); let v2: &[i32] = &[0, 1, 2, 3, 4]; let c2 = v2.array_windows::<6>(); assert_eq!(c2.count(), 0); let v3: &[i32] = &[]; let c3 = v3.array_windows::<2>(); assert_eq!(c3.count(), 0); let v4: &[()] = &[(); usize::MAX]; let c4 = v4.array_windows::<1>(); assert_eq!(c4.count(), usize::MAX); } #[test] fn test_array_windows_nth() { let v: &[i32] = &[0, 1, 2, 3, 4, 5]; let snd = v.array_windows::<4>().nth(1); assert_eq!(snd, Some(&[1, 2, 3, 4])); let mut arr_windows = v.array_windows::<2>(); assert_ne!(arr_windows.nth(0), arr_windows.nth(0)); let last = v.array_windows::<3>().last(); assert_eq!(last, Some(&[3, 4, 5])); } #[test] fn test_array_windows_nth_back() { let v: &[i32] = &[0, 1, 2, 3, 4, 5]; let snd = v.array_windows::<4>().nth_back(1); assert_eq!(snd, Some(&[1, 2, 3, 4])); let mut arr_windows = v.array_windows::<2>(); assert_ne!(arr_windows.nth_back(0), arr_windows.nth_back(0)); } #[test] fn test_rchunks_count() { let v: &[i32] = &[0, 1, 2, 3, 4, 5]; let c = v.rchunks(3); assert_eq!(c.count(), 2); let v2: &[i32] = &[0, 1, 2, 3, 4]; let c2 = v2.rchunks(2); assert_eq!(c2.count(), 3); let v3: &[i32] = &[]; let c3 = v3.rchunks(2); assert_eq!(c3.count(), 0); } #[test] fn test_rchunks_nth() { let v: &[i32] = &[0, 1, 2, 3, 4, 5]; let mut c = v.rchunks(2); assert_eq!(c.nth(1).unwrap(), &[2, 3]); assert_eq!(c.next().unwrap(), &[0, 1]); let v2: &[i32] = &[0, 1, 2, 3, 4]; let mut c2 = v2.rchunks(3); assert_eq!(c2.nth(1).unwrap(), &[0, 1]); assert_eq!(c2.next(), None); } #[test] fn test_rchunks_nth_back() { let v: &[i32] = &[0, 1, 2, 3, 4, 5]; let mut c = v.rchunks(2); assert_eq!(c.nth_back(1).unwrap(), &[2, 3]); assert_eq!(c.next_back().unwrap(), &[4, 5]); let v2: &[i32] = &[0, 1, 2, 3, 4]; let mut c2 = v2.rchunks(3); assert_eq!(c2.nth_back(1).unwrap(), &[2, 3, 4]); assert_eq!(c2.next_back(), None); } #[test] fn test_rchunks_next() { let v = [0, 1, 2, 3, 4, 5]; let mut c = v.rchunks(2); assert_eq!(c.next().unwrap(), &[4, 5]); assert_eq!(c.next().unwrap(), &[2, 3]); assert_eq!(c.next().unwrap(), &[0, 1]); assert_eq!(c.next(), None); let v = [0, 1, 2, 3, 4, 5, 6, 7]; let mut c = v.rchunks(3); assert_eq!(c.next().unwrap(), &[5, 6, 7]); assert_eq!(c.next().unwrap(), &[2, 3, 4]); assert_eq!(c.next().unwrap(), &[0, 1]); assert_eq!(c.next(), None); } #[test] fn test_rchunks_next_back() { let v = [0, 1, 2, 3, 4, 5]; let mut c = v.rchunks(2); assert_eq!(c.next_back().unwrap(), &[0, 1]); assert_eq!(c.next_back().unwrap(), &[2, 3]); assert_eq!(c.next_back().unwrap(), &[4, 5]); assert_eq!(c.next_back(), None); let v = [0, 1, 2, 3, 4, 5, 6, 7]; let mut c = v.rchunks(3); assert_eq!(c.next_back().unwrap(), &[0, 1]); assert_eq!(c.next_back().unwrap(), &[2, 3, 4]); assert_eq!(c.next_back().unwrap(), &[5, 6, 7]); assert_eq!(c.next_back(), None); } #[test] fn test_rchunks_last() { let v: &[i32] = &[0, 1, 2, 3, 4, 5]; let c = v.rchunks(2); assert_eq!(c.last().unwrap()[1], 1); let v2: &[i32] = &[0, 1, 2, 3, 4]; let c2 = v2.rchunks(2); assert_eq!(c2.last().unwrap()[0], 0); } #[test] fn test_rchunks_zip() { let v1: &[i32] = &[0, 1, 2, 3, 4]; let v2: &[i32] = &[6, 7, 8, 9, 10]; let res = v1 .rchunks(2) .zip(v2.rchunks(2)) .map(|(a, b)| a.iter().sum::() + b.iter().sum::()) .collect::>(); assert_eq!(res, vec![26, 18, 6]); } #[test] fn test_rchunks_mut_count() { let v: &mut [i32] = &mut [0, 1, 2, 3, 4, 5]; let c = v.rchunks_mut(3); assert_eq!(c.count(), 2); let v2: &mut [i32] = &mut [0, 1, 2, 3, 4]; let c2 = v2.rchunks_mut(2); assert_eq!(c2.count(), 3); let v3: &mut [i32] = &mut []; let c3 = v3.rchunks_mut(2); assert_eq!(c3.count(), 0); } #[test] fn test_rchunks_mut_nth() { let v: &mut [i32] = &mut [0, 1, 2, 3, 4, 5]; let mut c = v.rchunks_mut(2); assert_eq!(c.nth(1).unwrap(), &[2, 3]); assert_eq!(c.next().unwrap(), &[0, 1]); let v2: &mut [i32] = &mut [0, 1, 2, 3, 4]; let mut c2 = v2.rchunks_mut(3); assert_eq!(c2.nth(1).unwrap(), &[0, 1]); assert_eq!(c2.next(), None); } #[test] fn test_rchunks_mut_nth_back() { let v: &mut [i32] = &mut [0, 1, 2, 3, 4, 5]; let mut c = v.rchunks_mut(2); assert_eq!(c.nth_back(1).unwrap(), &[2, 3]); assert_eq!(c.next_back().unwrap(), &[4, 5]); let v2: &mut [i32] = &mut [0, 1, 2, 3, 4]; let mut c2 = v2.rchunks_mut(3); assert_eq!(c2.nth_back(1).unwrap(), &[2, 3, 4]); assert_eq!(c2.next_back(), None); } #[test] fn test_rchunks_mut_next() { let mut v = [0, 1, 2, 3, 4, 5]; let mut c = v.rchunks_mut(2); assert_eq!(c.next().unwrap(), &mut [4, 5]); assert_eq!(c.next().unwrap(), &mut [2, 3]); assert_eq!(c.next().unwrap(), &mut [0, 1]); assert_eq!(c.next(), None); let mut v = [0, 1, 2, 3, 4, 5, 6, 7]; let mut c = v.rchunks_mut(3); assert_eq!(c.next().unwrap(), &mut [5, 6, 7]); assert_eq!(c.next().unwrap(), &mut [2, 3, 4]); assert_eq!(c.next().unwrap(), &mut [0, 1]); assert_eq!(c.next(), None); } #[test] fn test_rchunks_mut_next_back() { let mut v = [0, 1, 2, 3, 4, 5]; let mut c = v.rchunks_mut(2); assert_eq!(c.next_back().unwrap(), &mut [0, 1]); assert_eq!(c.next_back().unwrap(), &mut [2, 3]); assert_eq!(c.next_back().unwrap(), &mut [4, 5]); assert_eq!(c.next_back(), None); let mut v = [0, 1, 2, 3, 4, 5, 6, 7]; let mut c = v.rchunks_mut(3); assert_eq!(c.next_back().unwrap(), &mut [0, 1]); assert_eq!(c.next_back().unwrap(), &mut [2, 3, 4]); assert_eq!(c.next_back().unwrap(), &mut [5, 6, 7]); assert_eq!(c.next_back(), None); } #[test] fn test_rchunks_mut_last() { let v: &mut [i32] = &mut [0, 1, 2, 3, 4, 5]; let c = v.rchunks_mut(2); assert_eq!(c.last().unwrap(), &[0, 1]); let v2: &mut [i32] = &mut [0, 1, 2, 3, 4]; let c2 = v2.rchunks_mut(2); assert_eq!(c2.last().unwrap(), &[0]); } #[test] fn test_rchunks_mut_zip() { let v1: &mut [i32] = &mut [0, 1, 2, 3, 4]; let v2: &[i32] = &[6, 7, 8, 9, 10]; for (a, b) in v1.rchunks_mut(2).zip(v2.rchunks(2)) { let sum = b.iter().sum::(); for v in a { *v += sum; } } assert_eq!(v1, [6, 16, 17, 22, 23]); } #[test] fn test_rchunks_exact_count() { let v: &[i32] = &[0, 1, 2, 3, 4, 5]; let c = v.rchunks_exact(3); assert_eq!(c.count(), 2); let v2: &[i32] = &[0, 1, 2, 3, 4]; let c2 = v2.rchunks_exact(2); assert_eq!(c2.count(), 2); let v3: &[i32] = &[]; let c3 = v3.rchunks_exact(2); assert_eq!(c3.count(), 0); } #[test] fn test_rchunks_exact_nth() { let v: &[i32] = &[0, 1, 2, 3, 4, 5]; let mut c = v.rchunks_exact(2); assert_eq!(c.nth(1).unwrap(), &[2, 3]); assert_eq!(c.next().unwrap(), &[0, 1]); let v2: &[i32] = &[0, 1, 2, 3, 4, 5, 6]; let mut c2 = v2.rchunks_exact(3); assert_eq!(c2.nth(1).unwrap(), &[1, 2, 3]); assert_eq!(c2.next(), None); } #[test] fn test_rchunks_exact_nth_back() { let v: &[i32] = &[0, 1, 2, 3, 4, 5]; let mut c = v.rchunks_exact(2); assert_eq!(c.nth_back(1).unwrap(), &[2, 3]); assert_eq!(c.next_back().unwrap(), &[4, 5]); let v2: &[i32] = &[0, 1, 2, 3, 4, 5, 6]; let mut c2 = v2.rchunks_exact(3); assert_eq!(c2.nth_back(1).unwrap(), &[4, 5, 6]); assert_eq!(c2.next(), None); } #[test] fn test_rchunks_exact_last() { let v: &[i32] = &[0, 1, 2, 3, 4, 5]; let c = v.rchunks_exact(2); assert_eq!(c.last().unwrap(), &[0, 1]); let v2: &[i32] = &[0, 1, 2, 3, 4]; let c2 = v2.rchunks_exact(2); assert_eq!(c2.last().unwrap(), &[1, 2]); } #[test] fn test_rchunks_exact_remainder() { let v: &[i32] = &[0, 1, 2, 3, 4]; let c = v.rchunks_exact(2); assert_eq!(c.remainder(), &[0]); } #[test] fn test_rchunks_exact_zip() { let v1: &[i32] = &[0, 1, 2, 3, 4]; let v2: &[i32] = &[6, 7, 8, 9, 10]; let res = v1 .rchunks_exact(2) .zip(v2.rchunks_exact(2)) .map(|(a, b)| a.iter().sum::() + b.iter().sum::()) .collect::>(); assert_eq!(res, vec![26, 18]); } #[test] fn test_rchunks_exact_mut_count() { let v: &mut [i32] = &mut [0, 1, 2, 3, 4, 5]; let c = v.rchunks_exact_mut(3); assert_eq!(c.count(), 2); let v2: &mut [i32] = &mut [0, 1, 2, 3, 4]; let c2 = v2.rchunks_exact_mut(2); assert_eq!(c2.count(), 2); let v3: &mut [i32] = &mut []; let c3 = v3.rchunks_exact_mut(2); assert_eq!(c3.count(), 0); } #[test] fn test_rchunks_exact_mut_nth() { let v: &mut [i32] = &mut [0, 1, 2, 3, 4, 5]; let mut c = v.rchunks_exact_mut(2); assert_eq!(c.nth(1).unwrap(), &[2, 3]); assert_eq!(c.next().unwrap(), &[0, 1]); let v2: &mut [i32] = &mut [0, 1, 2, 3, 4, 5, 6]; let mut c2 = v2.rchunks_exact_mut(3); assert_eq!(c2.nth(1).unwrap(), &[1, 2, 3]); assert_eq!(c2.next(), None); } #[test] fn test_rchunks_exact_mut_nth_back() { let v: &mut [i32] = &mut [0, 1, 2, 3, 4, 5]; let mut c = v.rchunks_exact_mut(2); assert_eq!(c.nth_back(1).unwrap(), &[2, 3]); assert_eq!(c.next_back().unwrap(), &[4, 5]); let v2: &mut [i32] = &mut [0, 1, 2, 3, 4, 5, 6]; let mut c2 = v2.rchunks_exact_mut(3); assert_eq!(c2.nth_back(1).unwrap(), &[4, 5, 6]); assert_eq!(c2.next(), None); } #[test] fn test_rchunks_exact_mut_last() { let v: &mut [i32] = &mut [0, 1, 2, 3, 4, 5]; let c = v.rchunks_exact_mut(2); assert_eq!(c.last().unwrap(), &[0, 1]); let v2: &mut [i32] = &mut [0, 1, 2, 3, 4]; let c2 = v2.rchunks_exact_mut(2); assert_eq!(c2.last().unwrap(), &[1, 2]); } #[test] fn test_rchunks_exact_mut_remainder() { let v: &mut [i32] = &mut [0, 1, 2, 3, 4]; let c = v.rchunks_exact_mut(2); assert_eq!(c.into_remainder(), &[0]); } #[test] fn test_rchunks_exact_mut_zip() { let v1: &mut [i32] = &mut [0, 1, 2, 3, 4]; let v2: &[i32] = &[6, 7, 8, 9, 10]; for (a, b) in v1.rchunks_exact_mut(2).zip(v2.rchunks_exact(2)) { let sum = b.iter().sum::(); for v in a { *v += sum; } } assert_eq!(v1, [0, 16, 17, 22, 23]); } #[test] fn chunks_mut_are_send_and_sync() { use std::cell::Cell; use std::slice::{ChunksExactMut, ChunksMut, RChunksExactMut, RChunksMut}; use std::sync::MutexGuard; #[allow(unused)] fn assert_send_and_sync() where ChunksMut<'static, Cell>: Send, ChunksMut<'static, MutexGuard<'static, u32>>: Sync, ChunksExactMut<'static, Cell>: Send, ChunksExactMut<'static, MutexGuard<'static, u32>>: Sync, RChunksMut<'static, Cell>: Send, RChunksMut<'static, MutexGuard<'static, u32>>: Sync, RChunksExactMut<'static, Cell>: Send, RChunksExactMut<'static, MutexGuard<'static, u32>>: Sync, { } } #[test] fn test_windows_count() { let v: &[i32] = &[0, 1, 2, 3, 4, 5]; let c = v.windows(3); assert_eq!(c.count(), 4); let v2: &[i32] = &[0, 1, 2, 3, 4]; let c2 = v2.windows(6); assert_eq!(c2.count(), 0); let v3: &[i32] = &[]; let c3 = v3.windows(2); assert_eq!(c3.count(), 0); let v4 = &[(); usize::MAX]; let c4 = v4.windows(1); assert_eq!(c4.count(), usize::MAX); } #[test] fn test_windows_nth() { let v: &[i32] = &[0, 1, 2, 3, 4, 5]; let mut c = v.windows(2); assert_eq!(c.nth(2).unwrap()[1], 3); assert_eq!(c.next().unwrap()[0], 3); let v2: &[i32] = &[0, 1, 2, 3, 4]; let mut c2 = v2.windows(4); assert_eq!(c2.nth(1).unwrap()[1], 2); assert_eq!(c2.next(), None); } #[test] fn test_windows_nth_back() { let v: &[i32] = &[0, 1, 2, 3, 4, 5]; let mut c = v.windows(2); assert_eq!(c.nth_back(2).unwrap()[0], 2); assert_eq!(c.next_back().unwrap()[1], 2); let v2: &[i32] = &[0, 1, 2, 3, 4]; let mut c2 = v2.windows(4); assert_eq!(c2.nth_back(1).unwrap()[1], 1); assert_eq!(c2.next_back(), None); } #[test] fn test_windows_last() { let v: &[i32] = &[0, 1, 2, 3, 4, 5]; let c = v.windows(2); assert_eq!(c.last().unwrap()[1], 5); let v2: &[i32] = &[0, 1, 2, 3, 4]; let c2 = v2.windows(2); assert_eq!(c2.last().unwrap()[0], 3); } #[test] fn test_windows_zip() { let v1: &[i32] = &[0, 1, 2, 3, 4]; let v2: &[i32] = &[6, 7, 8, 9, 10]; let res = v1 .windows(2) .zip(v2.windows(2)) .map(|(a, b)| a.iter().sum::() + b.iter().sum::()) .collect::>(); assert_eq!(res, [14, 18, 22, 26]); } #[test] #[allow(const_err)] fn test_iter_ref_consistency() { use std::fmt::Debug; fn test(x: T) { let v: &[T] = &[x, x, x]; let v_ptrs: [*const T; 3] = match v { [ref v1, ref v2, ref v3] => [v1 as *const _, v2 as *const _, v3 as *const _], _ => unreachable!(), }; let len = v.len(); // nth(i) for i in 0..len { assert_eq!(&v[i] as *const _, v_ptrs[i]); // check the v_ptrs array, just to be sure let nth = v.iter().nth(i).unwrap(); assert_eq!(nth as *const _, v_ptrs[i]); } assert_eq!(v.iter().nth(len), None, "nth(len) should return None"); // stepping through with nth(0) { let mut it = v.iter(); for i in 0..len { let next = it.nth(0).unwrap(); assert_eq!(next as *const _, v_ptrs[i]); } assert_eq!(it.nth(0), None); } // next() { let mut it = v.iter(); for i in 0..len { let remaining = len - i; assert_eq!(it.size_hint(), (remaining, Some(remaining))); let next = it.next().unwrap(); assert_eq!(next as *const _, v_ptrs[i]); } assert_eq!(it.size_hint(), (0, Some(0))); assert_eq!(it.next(), None, "The final call to next() should return None"); } // next_back() { let mut it = v.iter(); for i in 0..len { let remaining = len - i; assert_eq!(it.size_hint(), (remaining, Some(remaining))); let prev = it.next_back().unwrap(); assert_eq!(prev as *const _, v_ptrs[remaining - 1]); } assert_eq!(it.size_hint(), (0, Some(0))); assert_eq!(it.next_back(), None, "The final call to next_back() should return None"); } } fn test_mut(x: T) { let v: &mut [T] = &mut [x, x, x]; let v_ptrs: [*mut T; 3] = match v { [ref v1, ref v2, ref v3] => { [v1 as *const _ as *mut _, v2 as *const _ as *mut _, v3 as *const _ as *mut _] } _ => unreachable!(), }; let len = v.len(); // nth(i) for i in 0..len { assert_eq!(&mut v[i] as *mut _, v_ptrs[i]); // check the v_ptrs array, just to be sure let nth = v.iter_mut().nth(i).unwrap(); assert_eq!(nth as *mut _, v_ptrs[i]); } assert_eq!(v.iter().nth(len), None, "nth(len) should return None"); // stepping through with nth(0) { let mut it = v.iter(); for i in 0..len { let next = it.nth(0).unwrap(); assert_eq!(next as *const _, v_ptrs[i]); } assert_eq!(it.nth(0), None); } // next() { let mut it = v.iter_mut(); for i in 0..len { let remaining = len - i; assert_eq!(it.size_hint(), (remaining, Some(remaining))); let next = it.next().unwrap(); assert_eq!(next as *mut _, v_ptrs[i]); } assert_eq!(it.size_hint(), (0, Some(0))); assert_eq!(it.next(), None, "The final call to next() should return None"); } // next_back() { let mut it = v.iter_mut(); for i in 0..len { let remaining = len - i; assert_eq!(it.size_hint(), (remaining, Some(remaining))); let prev = it.next_back().unwrap(); assert_eq!(prev as *mut _, v_ptrs[remaining - 1]); } assert_eq!(it.size_hint(), (0, Some(0))); assert_eq!(it.next_back(), None, "The final call to next_back() should return None"); } } // Make sure iterators and slice patterns yield consistent addresses for various types, // including ZSTs. test(0u32); test(()); test([0u32; 0]); // ZST with alignment > 0 test_mut(0u32); test_mut(()); test_mut([0u32; 0]); // ZST with alignment > 0 } // The current implementation of SliceIndex fails to handle methods // orthogonally from range types; therefore, it is worth testing // all of the indexing operations on each input. mod slice_index { // This checks all six indexing methods, given an input range that // should succeed. (it is NOT suitable for testing invalid inputs) macro_rules! assert_range_eq { ($arr:expr, $range:expr, $expected:expr) => { let mut arr = $arr; let mut expected = $expected; { let s: &[_] = &arr; let expected: &[_] = &expected; assert_eq!(&s[$range], expected, "(in assertion for: index)"); assert_eq!(s.get($range), Some(expected), "(in assertion for: get)"); unsafe { assert_eq!( s.get_unchecked($range), expected, "(in assertion for: get_unchecked)", ); } } { let s: &mut [_] = &mut arr; let expected: &mut [_] = &mut expected; assert_eq!(&mut s[$range], expected, "(in assertion for: index_mut)",); assert_eq!( s.get_mut($range), Some(&mut expected[..]), "(in assertion for: get_mut)", ); unsafe { assert_eq!( s.get_unchecked_mut($range), expected, "(in assertion for: get_unchecked_mut)", ); } } }; } // Make sure the macro can actually detect bugs, // because if it can't, then what are we even doing here? // // (Be aware this only demonstrates the ability to detect bugs // in the FIRST method that panics, as the macro is not designed // to be used in `should_panic`) #[test] #[should_panic(expected = "out of range")] fn assert_range_eq_can_fail_by_panic() { assert_range_eq!([0, 1, 2], 0..5, [0, 1, 2]); } // (Be aware this only demonstrates the ability to detect bugs // in the FIRST method it calls, as the macro is not designed // to be used in `should_panic`) #[test] #[should_panic(expected = "==")] fn assert_range_eq_can_fail_by_inequality() { assert_range_eq!([0, 1, 2], 0..2, [0, 1, 2]); } // Test cases for bad index operations. // // This generates `should_panic` test cases for Index/IndexMut // and `None` test cases for get/get_mut. macro_rules! panic_cases { ($( // each test case needs a unique name to namespace the tests in mod $case_name:ident { data: $data:expr; // optional: // // one or more similar inputs for which data[input] succeeds, // and the corresponding output as an array. This helps validate // "critical points" where an input range straddles the boundary // between valid and invalid. // (such as the input `len..len`, which is just barely valid) $( good: data[$good:expr] == $output:expr; )* bad: data[$bad:expr]; message: $expect_msg:expr; } )*) => {$( mod $case_name { #[allow(unused_imports)] use core::ops::Bound; #[test] fn pass() { let mut v = $data; $( assert_range_eq!($data, $good, $output); )* { let v: &[_] = &v; assert_eq!(v.get($bad), None, "(in None assertion for get)"); } { let v: &mut [_] = &mut v; assert_eq!(v.get_mut($bad), None, "(in None assertion for get_mut)"); } } #[test] #[should_panic(expected = $expect_msg)] fn index_fail() { let v = $data; let v: &[_] = &v; let _v = &v[$bad]; } #[test] #[should_panic(expected = $expect_msg)] fn index_mut_fail() { let mut v = $data; let v: &mut [_] = &mut v; let _v = &mut v[$bad]; } } )*}; } #[test] fn simple() { let v = [0, 1, 2, 3, 4, 5]; assert_range_eq!(v, .., [0, 1, 2, 3, 4, 5]); assert_range_eq!(v, ..2, [0, 1]); assert_range_eq!(v, ..=1, [0, 1]); assert_range_eq!(v, 2.., [2, 3, 4, 5]); assert_range_eq!(v, 1..4, [1, 2, 3]); assert_range_eq!(v, 1..=3, [1, 2, 3]); } panic_cases! { in mod rangefrom_len { data: [0, 1, 2, 3, 4, 5]; good: data[6..] == []; bad: data[7..]; message: "out of range"; } in mod rangeto_len { data: [0, 1, 2, 3, 4, 5]; good: data[..6] == [0, 1, 2, 3, 4, 5]; bad: data[..7]; message: "out of range"; } in mod rangetoinclusive_len { data: [0, 1, 2, 3, 4, 5]; good: data[..=5] == [0, 1, 2, 3, 4, 5]; bad: data[..=6]; message: "out of range"; } in mod rangeinclusive_len { data: [0, 1, 2, 3, 4, 5]; good: data[0..=5] == [0, 1, 2, 3, 4, 5]; bad: data[0..=6]; message: "out of range"; } in mod range_len_len { data: [0, 1, 2, 3, 4, 5]; good: data[6..6] == []; bad: data[7..7]; message: "out of range"; } in mod rangeinclusive_len_len { data: [0, 1, 2, 3, 4, 5]; good: data[6..=5] == []; bad: data[7..=6]; message: "out of range"; } in mod boundpair_len { data: [0, 1, 2, 3, 4, 5]; good: data[(Bound::Included(6), Bound::Unbounded)] == []; good: data[(Bound::Unbounded, Bound::Included(5))] == [0, 1, 2, 3, 4, 5]; good: data[(Bound::Unbounded, Bound::Excluded(6))] == [0, 1, 2, 3, 4, 5]; good: data[(Bound::Included(0), Bound::Included(5))] == [0, 1, 2, 3, 4, 5]; good: data[(Bound::Included(0), Bound::Excluded(6))] == [0, 1, 2, 3, 4, 5]; good: data[(Bound::Included(2), Bound::Excluded(4))] == [2, 3]; good: data[(Bound::Excluded(1), Bound::Included(4))] == [2, 3, 4]; good: data[(Bound::Excluded(5), Bound::Excluded(6))] == []; good: data[(Bound::Included(6), Bound::Excluded(6))] == []; good: data[(Bound::Excluded(5), Bound::Included(5))] == []; good: data[(Bound::Included(6), Bound::Included(5))] == []; bad: data[(Bound::Unbounded, Bound::Included(6))]; message: "out of range"; } } panic_cases! { in mod rangeinclusive_exhausted { data: [0, 1, 2, 3, 4, 5]; good: data[0..=5] == [0, 1, 2, 3, 4, 5]; good: data[{ let mut iter = 0..=5; iter.by_ref().count(); // exhaust it iter }] == []; // 0..=6 is out of range before exhaustion, so it // stands to reason that it still would be after. bad: data[{ let mut iter = 0..=6; iter.by_ref().count(); // exhaust it iter }]; message: "out of range"; } } panic_cases! { in mod range_neg_width { data: [0, 1, 2, 3, 4, 5]; good: data[4..4] == []; bad: data[4..3]; message: "but ends at"; } in mod rangeinclusive_neg_width { data: [0, 1, 2, 3, 4, 5]; good: data[4..=3] == []; bad: data[4..=2]; message: "but ends at"; } in mod boundpair_neg_width { data: [0, 1, 2, 3, 4, 5]; good: data[(Bound::Included(4), Bound::Excluded(4))] == []; bad: data[(Bound::Included(4), Bound::Excluded(3))]; message: "but ends at"; } } panic_cases! { in mod rangeinclusive_overflow { data: [0, 1]; // note: using 0 specifically ensures that the result of overflowing is 0..0, // so that `get` doesn't simply return None for the wrong reason. bad: data[0 ..= usize::MAX]; message: "maximum usize"; } in mod rangetoinclusive_overflow { data: [0, 1]; bad: data[..= usize::MAX]; message: "maximum usize"; } in mod boundpair_overflow_end { data: [0; 1]; bad: data[(Bound::Unbounded, Bound::Included(usize::MAX))]; message: "maximum usize"; } in mod boundpair_overflow_start { data: [0; 1]; bad: data[(Bound::Excluded(usize::MAX), Bound::Unbounded)]; message: "maximum usize"; } } // panic_cases! } #[test] fn test_find_rfind() { let v = [0, 1, 2, 3, 4, 5]; let mut iter = v.iter(); let mut i = v.len(); while let Some(&elt) = iter.rfind(|_| true) { i -= 1; assert_eq!(elt, v[i]); } assert_eq!(i, 0); assert_eq!(v.iter().rfind(|&&x| x <= 3), Some(&3)); } #[test] fn test_iter_folds() { let a = [1, 2, 3, 4, 5]; // len>4 so the unroll is used assert_eq!(a.iter().fold(0, |acc, &x| 2 * acc + x), 57); assert_eq!(a.iter().rfold(0, |acc, &x| 2 * acc + x), 129); let fold = |acc: i32, &x| acc.checked_mul(2)?.checked_add(x); assert_eq!(a.iter().try_fold(0, &fold), Some(57)); assert_eq!(a.iter().try_rfold(0, &fold), Some(129)); // short-circuiting try_fold, through other methods let a = [0, 1, 2, 3, 5, 5, 5, 7, 8, 9]; let mut iter = a.iter(); assert_eq!(iter.position(|&x| x == 3), Some(3)); assert_eq!(iter.rfind(|&&x| x == 5), Some(&5)); assert_eq!(iter.len(), 2); } #[test] fn test_rotate_left() { const N: usize = 600; let a: &mut [_] = &mut [0; N]; for i in 0..N { a[i] = i; } a.rotate_left(42); let k = N - 42; for i in 0..N { assert_eq!(a[(i + k) % N], i); } } #[test] fn test_rotate_right() { const N: usize = 600; let a: &mut [_] = &mut [0; N]; for i in 0..N { a[i] = i; } a.rotate_right(42); for i in 0..N { assert_eq!(a[(i + 42) % N], i); } } #[test] #[cfg_attr(miri, ignore)] // Miri is too slow fn brute_force_rotate_test_0() { // In case of edge cases involving multiple algorithms let n = 300; for len in 0..n { for s in 0..len { let mut v = Vec::with_capacity(len); for i in 0..len { v.push(i); } v[..].rotate_right(s); for i in 0..v.len() { assert_eq!(v[i], v.len().wrapping_add(i.wrapping_sub(s)) % v.len()); } } } } #[test] fn brute_force_rotate_test_1() { // `ptr_rotate` covers so many kinds of pointer usage, that this is just a good test for // pointers in general. This uses a `[usize; 4]` to hit all algorithms without overwhelming miri let n = 30; for len in 0..n { for s in 0..len { let mut v: Vec<[usize; 4]> = Vec::with_capacity(len); for i in 0..len { v.push([i, 0, 0, 0]); } v[..].rotate_right(s); for i in 0..v.len() { assert_eq!(v[i][0], v.len().wrapping_add(i.wrapping_sub(s)) % v.len()); } } } } #[test] #[cfg(not(target_arch = "wasm32"))] fn sort_unstable() { use core::cmp::Ordering::{Equal, Greater, Less}; use core::slice::heapsort; use rand::{rngs::StdRng, seq::SliceRandom, Rng, SeedableRng}; // Miri is too slow (but still need to `chain` to make the types match) let lens = if cfg!(miri) { (2..20).chain(0..0) } else { (2..25).chain(500..510) }; let rounds = if cfg!(miri) { 1 } else { 100 }; let mut v = [0; 600]; let mut tmp = [0; 600]; let mut rng = StdRng::from_entropy(); for len in lens { let v = &mut v[0..len]; let tmp = &mut tmp[0..len]; for &modulus in &[5, 10, 100, 1000] { for _ in 0..rounds { for i in 0..len { v[i] = rng.gen::() % modulus; } // Sort in default order. tmp.copy_from_slice(v); tmp.sort_unstable(); assert!(tmp.windows(2).all(|w| w[0] <= w[1])); // Sort in ascending order. tmp.copy_from_slice(v); tmp.sort_unstable_by(|a, b| a.cmp(b)); assert!(tmp.windows(2).all(|w| w[0] <= w[1])); // Sort in descending order. tmp.copy_from_slice(v); tmp.sort_unstable_by(|a, b| b.cmp(a)); assert!(tmp.windows(2).all(|w| w[0] >= w[1])); // Test heapsort using `<` operator. tmp.copy_from_slice(v); heapsort(tmp, |a, b| a < b); assert!(tmp.windows(2).all(|w| w[0] <= w[1])); // Test heapsort using `>` operator. tmp.copy_from_slice(v); heapsort(tmp, |a, b| a > b); assert!(tmp.windows(2).all(|w| w[0] >= w[1])); } } } // Sort using a completely random comparison function. // This will reorder the elements *somehow*, but won't panic. for i in 0..v.len() { v[i] = i as i32; } v.sort_unstable_by(|_, _| *[Less, Equal, Greater].choose(&mut rng).unwrap()); v.sort_unstable(); for i in 0..v.len() { assert_eq!(v[i], i as i32); } // Should not panic. [0i32; 0].sort_unstable(); [(); 10].sort_unstable(); [(); 100].sort_unstable(); let mut v = [0xDEADBEEFu64]; v.sort_unstable(); assert!(v == [0xDEADBEEF]); } #[test] #[cfg(not(target_arch = "wasm32"))] #[cfg_attr(miri, ignore)] // Miri is too slow fn select_nth_unstable() { use core::cmp::Ordering::{Equal, Greater, Less}; use rand::rngs::StdRng; use rand::seq::SliceRandom; use rand::{Rng, SeedableRng}; let mut rng = StdRng::from_entropy(); for len in (2..21).chain(500..501) { let mut orig = vec![0; len]; for &modulus in &[5, 10, 1000] { for _ in 0..10 { for i in 0..len { orig[i] = rng.gen::() % modulus; } let v_sorted = { let mut v = orig.clone(); v.sort(); v }; // Sort in default order. for pivot in 0..len { let mut v = orig.clone(); v.select_nth_unstable(pivot); assert_eq!(v_sorted[pivot], v[pivot]); for i in 0..pivot { for j in pivot..len { assert!(v[i] <= v[j]); } } } // Sort in ascending order. for pivot in 0..len { let mut v = orig.clone(); let (left, pivot, right) = v.select_nth_unstable_by(pivot, |a, b| a.cmp(b)); assert_eq!(left.len() + right.len(), len - 1); for l in left { assert!(l <= pivot); for r in right.iter_mut() { assert!(l <= r); assert!(pivot <= r); } } } // Sort in descending order. let sort_descending_comparator = |a: &i32, b: &i32| b.cmp(a); let v_sorted_descending = { let mut v = orig.clone(); v.sort_by(sort_descending_comparator); v }; for pivot in 0..len { let mut v = orig.clone(); v.select_nth_unstable_by(pivot, sort_descending_comparator); assert_eq!(v_sorted_descending[pivot], v[pivot]); for i in 0..pivot { for j in pivot..len { assert!(v[j] <= v[i]); } } } } } } // Sort at index using a completely random comparison function. // This will reorder the elements *somehow*, but won't panic. let mut v = [0; 500]; for i in 0..v.len() { v[i] = i as i32; } for pivot in 0..v.len() { v.select_nth_unstable_by(pivot, |_, _| *[Less, Equal, Greater].choose(&mut rng).unwrap()); v.sort(); for i in 0..v.len() { assert_eq!(v[i], i as i32); } } // Should not panic. [(); 10].select_nth_unstable(0); [(); 10].select_nth_unstable(5); [(); 10].select_nth_unstable(9); [(); 100].select_nth_unstable(0); [(); 100].select_nth_unstable(50); [(); 100].select_nth_unstable(99); let mut v = [0xDEADBEEFu64]; v.select_nth_unstable(0); assert!(v == [0xDEADBEEF]); } #[test] #[should_panic(expected = "index 0 greater than length of slice")] fn select_nth_unstable_zero_length() { [0i32; 0].select_nth_unstable(0); } #[test] #[should_panic(expected = "index 20 greater than length of slice")] fn select_nth_unstable_past_length() { [0i32; 10].select_nth_unstable(20); } pub mod memchr { use core::slice::memchr::{memchr, memrchr}; // test fallback implementations on all platforms #[test] fn matches_one() { assert_eq!(Some(0), memchr(b'a', b"a")); } #[test] fn matches_begin() { assert_eq!(Some(0), memchr(b'a', b"aaaa")); } #[test] fn matches_end() { assert_eq!(Some(4), memchr(b'z', b"aaaaz")); } #[test] fn matches_nul() { assert_eq!(Some(4), memchr(b'\x00', b"aaaa\x00")); } #[test] fn matches_past_nul() { assert_eq!(Some(5), memchr(b'z', b"aaaa\x00z")); } #[test] fn no_match_empty() { assert_eq!(None, memchr(b'a', b"")); } #[test] fn no_match() { assert_eq!(None, memchr(b'a', b"xyz")); } #[test] fn matches_one_reversed() { assert_eq!(Some(0), memrchr(b'a', b"a")); } #[test] fn matches_begin_reversed() { assert_eq!(Some(3), memrchr(b'a', b"aaaa")); } #[test] fn matches_end_reversed() { assert_eq!(Some(0), memrchr(b'z', b"zaaaa")); } #[test] fn matches_nul_reversed() { assert_eq!(Some(4), memrchr(b'\x00', b"aaaa\x00")); } #[test] fn matches_past_nul_reversed() { assert_eq!(Some(0), memrchr(b'z', b"z\x00aaaa")); } #[test] fn no_match_empty_reversed() { assert_eq!(None, memrchr(b'a', b"")); } #[test] fn no_match_reversed() { assert_eq!(None, memrchr(b'a', b"xyz")); } #[test] fn each_alignment_reversed() { let mut data = [1u8; 64]; let needle = 2; let pos = 40; data[pos] = needle; for start in 0..16 { assert_eq!(Some(pos - start), memrchr(needle, &data[start..])); } } } #[test] fn test_align_to_simple() { let bytes = [1u8, 2, 3, 4, 5, 6, 7]; let (prefix, aligned, suffix) = unsafe { bytes.align_to::() }; assert_eq!(aligned.len(), 3); assert!(prefix == [1] || suffix == [7]); let expect1 = [1 << 8 | 2, 3 << 8 | 4, 5 << 8 | 6]; let expect2 = [1 | 2 << 8, 3 | 4 << 8, 5 | 6 << 8]; let expect3 = [2 << 8 | 3, 4 << 8 | 5, 6 << 8 | 7]; let expect4 = [2 | 3 << 8, 4 | 5 << 8, 6 | 7 << 8]; assert!( aligned == expect1 || aligned == expect2 || aligned == expect3 || aligned == expect4, "aligned={:?} expected={:?} || {:?} || {:?} || {:?}", aligned, expect1, expect2, expect3, expect4 ); } #[test] fn test_align_to_zst() { let bytes = [1, 2, 3, 4, 5, 6, 7]; let (prefix, aligned, suffix) = unsafe { bytes.align_to::<()>() }; assert_eq!(aligned.len(), 0); assert!(prefix == [1, 2, 3, 4, 5, 6, 7] || suffix == [1, 2, 3, 4, 5, 6, 7]); } #[test] fn test_align_to_non_trivial() { #[repr(align(8))] struct U64(u64, u64); #[repr(align(8))] struct U64U64U32(u64, u64, u32); let data = [ U64(1, 2), U64(3, 4), U64(5, 6), U64(7, 8), U64(9, 10), U64(11, 12), U64(13, 14), U64(15, 16), ]; let (prefix, aligned, suffix) = unsafe { data.align_to::() }; assert_eq!(aligned.len(), 4); assert_eq!(prefix.len() + suffix.len(), 2); } #[test] fn test_align_to_empty_mid() { use core::mem; // Make sure that we do not create empty unaligned slices for the mid part, even when the // overall slice is too short to contain an aligned address. let bytes = [1, 2, 3, 4, 5, 6, 7]; type Chunk = u32; for offset in 0..4 { let (_, mid, _) = unsafe { bytes[offset..offset + 1].align_to::() }; assert_eq!(mid.as_ptr() as usize % mem::align_of::(), 0); } } #[test] fn test_align_to_mut_aliasing() { let mut val = [1u8, 2, 3, 4, 5]; // `align_to_mut` used to create `mid` in a way that there was some intermediate // incorrect aliasing, invalidating the resulting `mid` slice. let (begin, mid, end) = unsafe { val.align_to_mut::<[u8; 2]>() }; assert!(begin.len() == 0); assert!(end.len() == 1); mid[0] = mid[1]; assert_eq!(val, [3, 4, 3, 4, 5]) } #[test] fn test_slice_partition_dedup_by() { let mut slice: [i32; 9] = [1, -1, 2, 3, 1, -5, 5, -2, 2]; let (dedup, duplicates) = slice.partition_dedup_by(|a, b| a.abs() == b.abs()); assert_eq!(dedup, [1, 2, 3, 1, -5, -2]); assert_eq!(duplicates, [5, -1, 2]); } #[test] fn test_slice_partition_dedup_empty() { let mut slice: [i32; 0] = []; let (dedup, duplicates) = slice.partition_dedup(); assert_eq!(dedup, []); assert_eq!(duplicates, []); } #[test] fn test_slice_partition_dedup_one() { let mut slice = [12]; let (dedup, duplicates) = slice.partition_dedup(); assert_eq!(dedup, [12]); assert_eq!(duplicates, []); } #[test] fn test_slice_partition_dedup_multiple_ident() { let mut slice = [12, 12, 12, 12, 12, 11, 11, 11, 11, 11, 11]; let (dedup, duplicates) = slice.partition_dedup(); assert_eq!(dedup, [12, 11]); assert_eq!(duplicates, [12, 12, 12, 12, 11, 11, 11, 11, 11]); } #[test] fn test_slice_partition_dedup_partialeq() { #[derive(Debug)] struct Foo(i32, i32); impl PartialEq for Foo { fn eq(&self, other: &Foo) -> bool { self.0 == other.0 } } let mut slice = [Foo(0, 1), Foo(0, 5), Foo(1, 7), Foo(1, 9)]; let (dedup, duplicates) = slice.partition_dedup(); assert_eq!(dedup, [Foo(0, 1), Foo(1, 7)]); assert_eq!(duplicates, [Foo(0, 5), Foo(1, 9)]); } #[test] fn test_copy_within() { // Start to end, with a RangeTo. let mut bytes = *b"Hello, World!"; bytes.copy_within(..3, 10); assert_eq!(&bytes, b"Hello, WorHel"); // End to start, with a RangeFrom. let mut bytes = *b"Hello, World!"; bytes.copy_within(10.., 0); assert_eq!(&bytes, b"ld!lo, World!"); // Overlapping, with a RangeInclusive. let mut bytes = *b"Hello, World!"; bytes.copy_within(0..=11, 1); assert_eq!(&bytes, b"HHello, World"); // Whole slice, with a RangeFull. let mut bytes = *b"Hello, World!"; bytes.copy_within(.., 0); assert_eq!(&bytes, b"Hello, World!"); // Ensure that copying at the end of slice won't cause UB. let mut bytes = *b"Hello, World!"; bytes.copy_within(13..13, 5); assert_eq!(&bytes, b"Hello, World!"); bytes.copy_within(5..5, 13); assert_eq!(&bytes, b"Hello, World!"); } #[test] #[should_panic(expected = "range end index 14 out of range for slice of length 13")] fn test_copy_within_panics_src_too_long() { let mut bytes = *b"Hello, World!"; // The length is only 13, so 14 is out of bounds. bytes.copy_within(10..14, 0); } #[test] #[should_panic(expected = "dest is out of bounds")] fn test_copy_within_panics_dest_too_long() { let mut bytes = *b"Hello, World!"; // The length is only 13, so a slice of length 4 starting at index 10 is out of bounds. bytes.copy_within(0..4, 10); } #[test] #[should_panic(expected = "slice index starts at 2 but ends at 1")] fn test_copy_within_panics_src_inverted() { let mut bytes = *b"Hello, World!"; // 2 is greater than 1, so this range is invalid. bytes.copy_within(2..1, 0); } #[test] #[should_panic(expected = "attempted to index slice up to maximum usize")] fn test_copy_within_panics_src_out_of_bounds() { let mut bytes = *b"Hello, World!"; // an inclusive range ending at usize::MAX would make src_end overflow bytes.copy_within(usize::MAX..=usize::MAX, 0); } #[test] fn test_is_sorted() { let empty: [i32; 0] = []; assert!([1, 2, 2, 9].is_sorted()); assert!(![1, 3, 2].is_sorted()); assert!([0].is_sorted()); assert!(empty.is_sorted()); assert!(![0.0, 1.0, f32::NAN].is_sorted()); assert!([-2, -1, 0, 3].is_sorted()); assert!(![-2i32, -1, 0, 3].is_sorted_by_key(|n| n.abs())); assert!(!["c", "bb", "aaa"].is_sorted()); assert!(["c", "bb", "aaa"].is_sorted_by_key(|s| s.len())); } #[test] fn test_slice_run_destructors() { // Make sure that destructors get run on slice literals struct Foo<'a> { x: &'a Cell, } impl<'a> Drop for Foo<'a> { fn drop(&mut self) { self.x.set(self.x.get() + 1); } } fn foo(x: &Cell) -> Foo<'_> { Foo { x } } let x = &Cell::new(0); { let l = &[foo(x)]; assert_eq!(l[0].x.get(), 0); } assert_eq!(x.get(), 1); } #[test] fn test_const_from_ref() { const VALUE: &i32 = &1; const SLICE: &[i32] = core::slice::from_ref(VALUE); assert!(core::ptr::eq(VALUE, &SLICE[0])) } #[test] fn test_slice_fill_with_uninit() { // This should not UB. See #87891 let mut a = [MaybeUninit::::uninit(); 10]; a.fill(MaybeUninit::uninit()); } #[test] fn test_swap() { let mut x = ["a", "b", "c", "d"]; x.swap(1, 3); assert_eq!(x, ["a", "d", "c", "b"]); x.swap(0, 3); assert_eq!(x, ["b", "d", "c", "a"]); } mod swap_panics { #[test] #[should_panic(expected = "index out of bounds: the len is 4 but the index is 4")] fn index_a_equals_len() { let mut x = ["a", "b", "c", "d"]; x.swap(4, 2); } #[test] #[should_panic(expected = "index out of bounds: the len is 4 but the index is 4")] fn index_b_equals_len() { let mut x = ["a", "b", "c", "d"]; x.swap(2, 4); } #[test] #[should_panic(expected = "index out of bounds: the len is 4 but the index is 5")] fn index_a_greater_than_len() { let mut x = ["a", "b", "c", "d"]; x.swap(5, 2); } #[test] #[should_panic(expected = "index out of bounds: the len is 4 but the index is 5")] fn index_b_greater_than_len() { let mut x = ["a", "b", "c", "d"]; x.swap(2, 5); } } #[test] fn slice_split_array_mut() { let v = &mut [1, 2, 3, 4, 5, 6][..]; { let (left, right) = v.split_array_mut::<0>(); assert_eq!(left, &mut []); assert_eq!(right, [1, 2, 3, 4, 5, 6]); } { let (left, right) = v.split_array_mut::<6>(); assert_eq!(left, &mut [1, 2, 3, 4, 5, 6]); assert_eq!(right, []); } } #[test] fn slice_rsplit_array_mut() { let v = &mut [1, 2, 3, 4, 5, 6][..]; { let (left, right) = v.rsplit_array_mut::<0>(); assert_eq!(left, [1, 2, 3, 4, 5, 6]); assert_eq!(right, &mut []); } { let (left, right) = v.rsplit_array_mut::<6>(); assert_eq!(left, []); assert_eq!(right, &mut [1, 2, 3, 4, 5, 6]); } } #[test] fn split_as_slice() { let arr = [1, 2, 3, 4, 5, 6]; let mut split = arr.split(|v| v % 2 == 0); assert_eq!(split.as_slice(), &[1, 2, 3, 4, 5, 6]); assert!(split.next().is_some()); assert_eq!(split.as_slice(), &[3, 4, 5, 6]); assert!(split.next().is_some()); assert!(split.next().is_some()); assert_eq!(split.as_slice(), &[]); } #[should_panic] #[test] fn slice_split_array_ref_out_of_bounds() { let v = &[1, 2, 3, 4, 5, 6][..]; let _ = v.split_array_ref::<7>(); } #[should_panic] #[test] fn slice_split_array_mut_out_of_bounds() { let v = &mut [1, 2, 3, 4, 5, 6][..]; let _ = v.split_array_mut::<7>(); } #[should_panic] #[test] fn slice_rsplit_array_ref_out_of_bounds() { let v = &[1, 2, 3, 4, 5, 6][..]; let _ = v.rsplit_array_ref::<7>(); } #[should_panic] #[test] fn slice_rsplit_array_mut_out_of_bounds() { let v = &mut [1, 2, 3, 4, 5, 6][..]; let _ = v.rsplit_array_mut::<7>(); } macro_rules! take_tests { (slice: &[], $($tts:tt)*) => { take_tests!(ty: &[()], slice: &[], $($tts)*); }; (slice: &mut [], $($tts:tt)*) => { take_tests!(ty: &mut [()], slice: &mut [], $($tts)*); }; (slice: &$slice:expr, $($tts:tt)*) => { take_tests!(ty: &[_], slice: &$slice, $($tts)*); }; (slice: &mut $slice:expr, $($tts:tt)*) => { take_tests!(ty: &mut [_], slice: &mut $slice, $($tts)*); }; (ty: $ty:ty, slice: $slice:expr, method: $method:ident, $(($test_name:ident, ($($args:expr),*), $output:expr, $remaining:expr),)*) => { $( #[test] fn $test_name() { let mut slice: $ty = $slice; assert_eq!($output, slice.$method($($args)*)); let remaining: $ty = $remaining; assert_eq!(remaining, slice); } )* }; } take_tests! { slice: &[0, 1, 2, 3], method: take, (take_in_bounds_range_to, (..1), Some(&[0] as _), &[1, 2, 3]), (take_in_bounds_range_to_inclusive, (..=0), Some(&[0] as _), &[1, 2, 3]), (take_in_bounds_range_from, (2..), Some(&[2, 3] as _), &[0, 1]), (take_oob_range_to, (..5), None, &[0, 1, 2, 3]), (take_oob_range_to_inclusive, (..=4), None, &[0, 1, 2, 3]), (take_oob_range_from, (5..), None, &[0, 1, 2, 3]), } take_tests! { slice: &mut [0, 1, 2, 3], method: take_mut, (take_mut_in_bounds_range_to, (..1), Some(&mut [0] as _), &mut [1, 2, 3]), (take_mut_in_bounds_range_to_inclusive, (..=0), Some(&mut [0] as _), &mut [1, 2, 3]), (take_mut_in_bounds_range_from, (2..), Some(&mut [2, 3] as _), &mut [0, 1]), (take_mut_oob_range_to, (..5), None, &mut [0, 1, 2, 3]), (take_mut_oob_range_to_inclusive, (..=4), None, &mut [0, 1, 2, 3]), (take_mut_oob_range_from, (5..), None, &mut [0, 1, 2, 3]), } take_tests! { slice: &[1, 2], method: take_first, (take_first_nonempty, (), Some(&1), &[2]), } take_tests! { slice: &mut [1, 2], method: take_first_mut, (take_first_mut_nonempty, (), Some(&mut 1), &mut [2]), } take_tests! { slice: &[1, 2], method: take_last, (take_last_nonempty, (), Some(&2), &[1]), } take_tests! { slice: &mut [1, 2], method: take_last_mut, (take_last_mut_nonempty, (), Some(&mut 2), &mut [1]), } take_tests! { slice: &[], method: take_first, (take_first_empty, (), None, &[]), } take_tests! { slice: &mut [], method: take_first_mut, (take_first_mut_empty, (), None, &mut []), } take_tests! { slice: &[], method: take_last, (take_last_empty, (), None, &[]), } take_tests! { slice: &mut [], method: take_last_mut, (take_last_mut_empty, (), None, &mut []), } #[cfg(not(miri))] // unused in Miri const EMPTY_MAX: &'static [()] = &[(); usize::MAX]; // can't be a constant due to const mutability rules #[cfg(not(miri))] // unused in Miri macro_rules! empty_max_mut { () => { &mut [(); usize::MAX] as _ }; } #[cfg(not(miri))] // Comparing usize::MAX many elements takes forever in Miri (and in rustc without optimizations) take_tests! { slice: &[(); usize::MAX], method: take, (take_in_bounds_max_range_to, (..usize::MAX), Some(EMPTY_MAX), &[(); 0]), (take_oob_max_range_to_inclusive, (..=usize::MAX), None, EMPTY_MAX), (take_in_bounds_max_range_from, (usize::MAX..), Some(&[] as _), EMPTY_MAX), } #[cfg(not(miri))] // Comparing usize::MAX many elements takes forever in Miri (and in rustc without optimizations) take_tests! { slice: &mut [(); usize::MAX], method: take_mut, (take_mut_in_bounds_max_range_to, (..usize::MAX), Some(empty_max_mut!()), &mut [(); 0]), (take_mut_oob_max_range_to_inclusive, (..=usize::MAX), None, empty_max_mut!()), (take_mut_in_bounds_max_range_from, (usize::MAX..), Some(&mut [] as _), empty_max_mut!()), } #[test] fn test_slice_from_ptr_range() { let arr = ["foo".to_owned(), "bar".to_owned()]; let range = arr.as_ptr_range(); unsafe { assert_eq!(slice::from_ptr_range(range), &arr); } let mut arr = [1, 2, 3]; let range = arr.as_mut_ptr_range(); unsafe { assert_eq!(slice::from_mut_ptr_range(range), &mut [1, 2, 3]); } let arr: [Vec; 0] = []; let range = arr.as_ptr_range(); unsafe { assert_eq!(slice::from_ptr_range(range), &arr); } } #[test] #[should_panic = "slice len overflow"] fn test_flatten_size_overflow() { let x = &[[(); usize::MAX]; 2][..]; let _ = x.flatten(); } #[test] #[should_panic = "slice len overflow"] fn test_flatten_mut_size_overflow() { let x = &mut [[(); usize::MAX]; 2][..]; let _ = x.flatten_mut(); }