rust/src/liballoc/tests/slice.rs

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// Copyright 2012-2015 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
use std::cell::Cell;
use std::cmp::Ordering::{Equal, Greater, Less};
use std::cmp::Ordering;
use std::mem;
use std::panic;
use std::rc::Rc;
use std::sync::atomic::Ordering::Relaxed;
use std::sync::atomic::{ATOMIC_USIZE_INIT, AtomicUsize};
use std::thread;
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use rand::{Rng, RngCore, thread_rng};
use rand::distributions::Standard;
fn square(n: usize) -> usize {
n * n
}
fn is_odd(n: &usize) -> bool {
*n % 2 == 1
}
#[test]
fn test_from_fn() {
// Test on-stack from_fn.
let mut v: Vec<_> = (0..3).map(square).collect();
{
let v = v;
assert_eq!(v.len(), 3);
assert_eq!(v[0], 0);
assert_eq!(v[1], 1);
assert_eq!(v[2], 4);
}
// Test on-heap from_fn.
v = (0..5).map(square).collect();
{
let v = v;
assert_eq!(v.len(), 5);
assert_eq!(v[0], 0);
assert_eq!(v[1], 1);
assert_eq!(v[2], 4);
assert_eq!(v[3], 9);
assert_eq!(v[4], 16);
}
}
#[test]
fn test_from_elem() {
// Test on-stack from_elem.
let mut v = vec![10, 10];
{
let v = v;
assert_eq!(v.len(), 2);
assert_eq!(v[0], 10);
assert_eq!(v[1], 10);
}
// Test on-heap from_elem.
v = vec![20; 6];
{
let v = &v[..];
assert_eq!(v[0], 20);
assert_eq!(v[1], 20);
assert_eq!(v[2], 20);
assert_eq!(v[3], 20);
assert_eq!(v[4], 20);
assert_eq!(v[5], 20);
}
}
#[test]
fn test_is_empty() {
let xs: [i32; 0] = [];
assert!(xs.is_empty());
assert!(![0].is_empty());
}
#[test]
fn test_len_divzero() {
type Z = [i8; 0];
let v0: &[Z] = &[];
let v1: &[Z] = &[[]];
let v2: &[Z] = &[[], []];
assert_eq!(mem::size_of::<Z>(), 0);
assert_eq!(v0.len(), 0);
assert_eq!(v1.len(), 1);
assert_eq!(v2.len(), 2);
}
#[test]
fn test_get() {
let mut a = vec![11];
assert_eq!(a.get(1), None);
a = vec![11, 12];
assert_eq!(a.get(1).unwrap(), &12);
a = vec![11, 12, 13];
assert_eq!(a.get(1).unwrap(), &12);
}
#[test]
fn test_first() {
let mut a = vec![];
assert_eq!(a.first(), None);
a = vec![11];
assert_eq!(a.first().unwrap(), &11);
a = vec![11, 12];
assert_eq!(a.first().unwrap(), &11);
}
#[test]
fn test_first_mut() {
let mut a = vec![];
assert_eq!(a.first_mut(), None);
a = vec![11];
assert_eq!(*a.first_mut().unwrap(), 11);
a = vec![11, 12];
assert_eq!(*a.first_mut().unwrap(), 11);
}
#[test]
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fn test_split_first() {
let mut a = vec![11];
let b: &[i32] = &[];
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assert!(b.split_first().is_none());
assert_eq!(a.split_first(), Some((&11, b)));
a = vec![11, 12];
let b: &[i32] = &[12];
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assert_eq!(a.split_first(), Some((&11, b)));
}
#[test]
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fn test_split_first_mut() {
let mut a = vec![11];
let b: &mut [i32] = &mut [];
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assert!(b.split_first_mut().is_none());
assert!(a.split_first_mut() == Some((&mut 11, b)));
a = vec![11, 12];
let b: &mut [_] = &mut [12];
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assert!(a.split_first_mut() == Some((&mut 11, b)));
}
#[test]
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fn test_split_last() {
let mut a = vec![11];
let b: &[i32] = &[];
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assert!(b.split_last().is_none());
assert_eq!(a.split_last(), Some((&11, b)));
a = vec![11, 12];
let b: &[_] = &[11];
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assert_eq!(a.split_last(), Some((&12, b)));
}
#[test]
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fn test_split_last_mut() {
let mut a = vec![11];
let b: &mut [i32] = &mut [];
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assert!(b.split_last_mut().is_none());
assert!(a.split_last_mut() == Some((&mut 11, b)));
a = vec![11, 12];
let b: &mut [_] = &mut [11];
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assert!(a.split_last_mut() == Some((&mut 12, b)));
}
#[test]
fn test_last() {
let mut a = vec![];
assert_eq!(a.last(), None);
a = vec![11];
assert_eq!(a.last().unwrap(), &11);
a = vec![11, 12];
assert_eq!(a.last().unwrap(), &12);
}
#[test]
fn test_last_mut() {
let mut a = vec![];
assert_eq!(a.last_mut(), None);
a = vec![11];
assert_eq!(*a.last_mut().unwrap(), 11);
a = vec![11, 12];
assert_eq!(*a.last_mut().unwrap(), 12);
}
#[test]
fn test_slice() {
// Test fixed length vector.
let vec_fixed = [1, 2, 3, 4];
let v_a = vec_fixed[1..vec_fixed.len()].to_vec();
assert_eq!(v_a.len(), 3);
assert_eq!(v_a[0], 2);
assert_eq!(v_a[1], 3);
assert_eq!(v_a[2], 4);
// Test on stack.
let vec_stack: &[_] = &[1, 2, 3];
let v_b = vec_stack[1..3].to_vec();
assert_eq!(v_b.len(), 2);
assert_eq!(v_b[0], 2);
assert_eq!(v_b[1], 3);
// Test `Box<[T]>`
let vec_unique = vec![1, 2, 3, 4, 5, 6];
let v_d = vec_unique[1..6].to_vec();
assert_eq!(v_d.len(), 5);
assert_eq!(v_d[0], 2);
assert_eq!(v_d[1], 3);
assert_eq!(v_d[2], 4);
assert_eq!(v_d[3], 5);
assert_eq!(v_d[4], 6);
}
#[test]
fn test_slice_from() {
let vec: &[_] = &[1, 2, 3, 4];
assert_eq!(&vec[..], vec);
let b: &[_] = &[3, 4];
assert_eq!(&vec[2..], b);
let b: &[_] = &[];
assert_eq!(&vec[4..], b);
}
#[test]
fn test_slice_to() {
let vec: &[_] = &[1, 2, 3, 4];
assert_eq!(&vec[..4], vec);
let b: &[_] = &[1, 2];
assert_eq!(&vec[..2], b);
let b: &[_] = &[];
assert_eq!(&vec[..0], b);
}
#[test]
fn test_pop() {
let mut v = vec![5];
let e = v.pop();
assert_eq!(v.len(), 0);
assert_eq!(e, Some(5));
let f = v.pop();
assert_eq!(f, None);
let g = v.pop();
assert_eq!(g, None);
}
#[test]
fn test_swap_remove() {
let mut v = vec![1, 2, 3, 4, 5];
let mut e = v.swap_remove(0);
assert_eq!(e, 1);
assert_eq!(v, [5, 2, 3, 4]);
e = v.swap_remove(3);
assert_eq!(e, 4);
assert_eq!(v, [5, 2, 3]);
}
#[test]
#[should_panic]
fn test_swap_remove_fail() {
let mut v = vec![1];
let _ = v.swap_remove(0);
let _ = v.swap_remove(0);
}
#[test]
fn test_swap_remove_noncopyable() {
// Tests that we don't accidentally run destructors twice.
let mut v: Vec<Box<_>> = Vec::new();
v.push(box 0);
v.push(box 0);
v.push(box 0);
let mut _e = v.swap_remove(0);
assert_eq!(v.len(), 2);
_e = v.swap_remove(1);
assert_eq!(v.len(), 1);
_e = v.swap_remove(0);
assert_eq!(v.len(), 0);
}
#[test]
fn test_push() {
// Test on-stack push().
let mut v = vec![];
v.push(1);
assert_eq!(v.len(), 1);
assert_eq!(v[0], 1);
// Test on-heap push().
v.push(2);
assert_eq!(v.len(), 2);
assert_eq!(v[0], 1);
assert_eq!(v[1], 2);
}
#[test]
fn test_truncate() {
let mut v: Vec<Box<_>> = vec![box 6, box 5, box 4];
v.truncate(1);
let v = v;
assert_eq!(v.len(), 1);
assert_eq!(*(v[0]), 6);
// If the unsafe block didn't drop things properly, we blow up here.
}
#[test]
fn test_clear() {
let mut v: Vec<Box<_>> = vec![box 6, box 5, box 4];
v.clear();
assert_eq!(v.len(), 0);
// If the unsafe block didn't drop things properly, we blow up here.
}
#[test]
fn test_retain() {
let mut v = vec![1, 2, 3, 4, 5];
v.retain(is_odd);
assert_eq!(v, [1, 3, 5]);
}
#[test]
fn test_binary_search() {
assert_eq!([1, 2, 3, 4, 5].binary_search(&5).ok(), Some(4));
assert_eq!([1, 2, 3, 4, 5].binary_search(&4).ok(), Some(3));
assert_eq!([1, 2, 3, 4, 5].binary_search(&3).ok(), Some(2));
assert_eq!([1, 2, 3, 4, 5].binary_search(&2).ok(), Some(1));
assert_eq!([1, 2, 3, 4, 5].binary_search(&1).ok(), Some(0));
assert_eq!([2, 4, 6, 8, 10].binary_search(&1).ok(), None);
assert_eq!([2, 4, 6, 8, 10].binary_search(&5).ok(), None);
assert_eq!([2, 4, 6, 8, 10].binary_search(&4).ok(), Some(1));
assert_eq!([2, 4, 6, 8, 10].binary_search(&10).ok(), Some(4));
assert_eq!([2, 4, 6, 8].binary_search(&1).ok(), None);
assert_eq!([2, 4, 6, 8].binary_search(&5).ok(), None);
assert_eq!([2, 4, 6, 8].binary_search(&4).ok(), Some(1));
assert_eq!([2, 4, 6, 8].binary_search(&8).ok(), Some(3));
assert_eq!([2, 4, 6].binary_search(&1).ok(), None);
assert_eq!([2, 4, 6].binary_search(&5).ok(), None);
assert_eq!([2, 4, 6].binary_search(&4).ok(), Some(1));
assert_eq!([2, 4, 6].binary_search(&6).ok(), Some(2));
assert_eq!([2, 4].binary_search(&1).ok(), None);
assert_eq!([2, 4].binary_search(&5).ok(), None);
assert_eq!([2, 4].binary_search(&2).ok(), Some(0));
assert_eq!([2, 4].binary_search(&4).ok(), Some(1));
assert_eq!([2].binary_search(&1).ok(), None);
assert_eq!([2].binary_search(&5).ok(), None);
assert_eq!([2].binary_search(&2).ok(), Some(0));
assert_eq!([].binary_search(&1).ok(), None);
assert_eq!([].binary_search(&5).ok(), None);
assert!([1, 1, 1, 1, 1].binary_search(&1).ok() != None);
assert!([1, 1, 1, 1, 2].binary_search(&1).ok() != None);
assert!([1, 1, 1, 2, 2].binary_search(&1).ok() != None);
assert!([1, 1, 2, 2, 2].binary_search(&1).ok() != None);
assert_eq!([1, 2, 2, 2, 2].binary_search(&1).ok(), Some(0));
assert_eq!([1, 2, 3, 4, 5].binary_search(&6).ok(), None);
assert_eq!([1, 2, 3, 4, 5].binary_search(&0).ok(), None);
}
#[test]
fn test_reverse() {
let mut v = vec![10, 20];
assert_eq!(v[0], 10);
assert_eq!(v[1], 20);
v.reverse();
assert_eq!(v[0], 20);
assert_eq!(v[1], 10);
let mut v3 = Vec::<i32>::new();
v3.reverse();
assert!(v3.is_empty());
// check the 1-byte-types path
let mut v = (-50..51i8).collect::<Vec<_>>();
v.reverse();
assert_eq!(v, (-50..51i8).rev().collect::<Vec<_>>());
// check the 2-byte-types path
let mut v = (-50..51i16).collect::<Vec<_>>();
v.reverse();
assert_eq!(v, (-50..51i16).rev().collect::<Vec<_>>());
}
#[test]
fn test_sort() {
let mut rng = thread_rng();
for len in (2..25).chain(500..510) {
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for &modulus in &[5, 10, 100, 1000] {
for _ in 0..10 {
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let orig: Vec<_> = rng.sample_iter::<i32, _>(&Standard)
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.map(|x| x % modulus)
.take(len)
.collect();
// Sort in default order.
let mut v = orig.clone();
v.sort();
assert!(v.windows(2).all(|w| w[0] <= w[1]));
// Sort in ascending order.
let mut v = orig.clone();
v.sort_by(|a, b| a.cmp(b));
assert!(v.windows(2).all(|w| w[0] <= w[1]));
// Sort in descending order.
let mut v = orig.clone();
v.sort_by(|a, b| b.cmp(a));
assert!(v.windows(2).all(|w| w[0] >= w[1]));
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// Sort in lexicographic order.
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let mut v1 = orig.clone();
let mut v2 = orig.clone();
v1.sort_by_key(|x| x.to_string());
v2.sort_by_cached_key(|x| x.to_string());
assert!(v1.windows(2).all(|w| w[0].to_string() <= w[1].to_string()));
assert!(v1 == v2);
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// Sort with many pre-sorted runs.
let mut v = orig.clone();
v.sort();
v.reverse();
for _ in 0..5 {
let a = rng.gen::<usize>() % len;
let b = rng.gen::<usize>() % len;
if a < b {
v[a..b].reverse();
} else {
v.swap(a, b);
}
}
v.sort();
assert!(v.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.
let mut v = [0; 500];
for i in 0..v.len() {
v[i] = i as i32;
}
v.sort_by(|_, _| *rng.choose(&[Less, Equal, Greater]).unwrap());
v.sort();
for i in 0..v.len() {
assert_eq!(v[i], i as i32);
}
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// Should not panic.
[0i32; 0].sort();
[(); 10].sort();
[(); 100].sort();
let mut v = [0xDEADBEEFu64];
v.sort();
assert!(v == [0xDEADBEEF]);
}
#[test]
fn test_sort_stability() {
for len in (2..25).chain(500..510) {
for _ in 0..10 {
let mut counts = [0; 10];
// create a vector like [(6, 1), (5, 1), (6, 2), ...],
// where the first item of each tuple is random, but
// the second item represents which occurrence of that
// number this element is, i.e., the second elements
// will occur in sorted order.
let mut orig: Vec<_> = (0..len)
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.map(|_| {
let n = thread_rng().gen::<usize>() % 10;
counts[n] += 1;
(n, counts[n])
})
.collect();
let mut v = orig.clone();
// Only sort on the first element, so an unstable sort
// may mix up the counts.
v.sort_by(|&(a, _), &(b, _)| a.cmp(&b));
// This comparison includes the count (the second item
// of the tuple), so elements with equal first items
// will need to be ordered with increasing
// counts... i.e., exactly asserting that this sort is
// stable.
assert!(v.windows(2).all(|w| w[0] <= w[1]));
let mut v = orig.clone();
v.sort_by_cached_key(|&(x, _)| x);
assert!(v.windows(2).all(|w| w[0] <= w[1]));
}
}
}
#[test]
Deprecate [T]::rotate in favor of [T]::rotate_{left,right}. Background ========== Slices currently have an unstable [`rotate`] method which rotates elements in the slice to the _left_ N positions. [Here][tracking] is the tracking issue for this unstable feature. ```rust let mut a = ['a', 'b' ,'c', 'd', 'e', 'f']; a.rotate(2); assert_eq!(a, ['c', 'd', 'e', 'f', 'a', 'b']); ``` Proposal ======== Deprecate the [`rotate`] method and introduce `rotate_left` and `rotate_right` methods. ```rust let mut a = ['a', 'b' ,'c', 'd', 'e', 'f']; a.rotate_left(2); assert_eq!(a, ['c', 'd', 'e', 'f', 'a', 'b']); ``` ```rust let mut a = ['a', 'b' ,'c', 'd', 'e', 'f']; a.rotate_right(2); assert_eq!(a, ['e', 'f', 'a', 'b', 'c', 'd']); ``` Justification ============= I used this method today for my first time and (probably because I’m a naive westerner who reads LTR) was surprised when the docs mentioned that elements get rotated in a left-ward direction. I was in a situation where I needed to shift elements in a right-ward direction and had to context switch from the main problem I was working on and think how much to rotate left in order to accomplish the right-ward rotation I needed. Ruby’s `Array.rotate` shifts left-ward, Python’s `deque.rotate` shifts right-ward. Both of their implementations allow passing negative numbers to shift in the opposite direction respectively. Introducing `rotate_left` and `rotate_right` would: - remove ambiguity about direction (alleviating need to read docs 😉) - make it easier for people who need to rotate right [`rotate`]: https://doc.rust-lang.org/std/primitive.slice.html#method.rotate [tracking]: https://github.com/rust-lang/rust/issues/41891
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fn test_rotate_left() {
let expected: Vec<_> = (0..13).collect();
let mut v = Vec::new();
// no-ops
v.clone_from(&expected);
Deprecate [T]::rotate in favor of [T]::rotate_{left,right}. Background ========== Slices currently have an unstable [`rotate`] method which rotates elements in the slice to the _left_ N positions. [Here][tracking] is the tracking issue for this unstable feature. ```rust let mut a = ['a', 'b' ,'c', 'd', 'e', 'f']; a.rotate(2); assert_eq!(a, ['c', 'd', 'e', 'f', 'a', 'b']); ``` Proposal ======== Deprecate the [`rotate`] method and introduce `rotate_left` and `rotate_right` methods. ```rust let mut a = ['a', 'b' ,'c', 'd', 'e', 'f']; a.rotate_left(2); assert_eq!(a, ['c', 'd', 'e', 'f', 'a', 'b']); ``` ```rust let mut a = ['a', 'b' ,'c', 'd', 'e', 'f']; a.rotate_right(2); assert_eq!(a, ['e', 'f', 'a', 'b', 'c', 'd']); ``` Justification ============= I used this method today for my first time and (probably because I’m a naive westerner who reads LTR) was surprised when the docs mentioned that elements get rotated in a left-ward direction. I was in a situation where I needed to shift elements in a right-ward direction and had to context switch from the main problem I was working on and think how much to rotate left in order to accomplish the right-ward rotation I needed. Ruby’s `Array.rotate` shifts left-ward, Python’s `deque.rotate` shifts right-ward. Both of their implementations allow passing negative numbers to shift in the opposite direction respectively. Introducing `rotate_left` and `rotate_right` would: - remove ambiguity about direction (alleviating need to read docs 😉) - make it easier for people who need to rotate right [`rotate`]: https://doc.rust-lang.org/std/primitive.slice.html#method.rotate [tracking]: https://github.com/rust-lang/rust/issues/41891
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v.rotate_left(0);
assert_eq!(v, expected);
Deprecate [T]::rotate in favor of [T]::rotate_{left,right}. Background ========== Slices currently have an unstable [`rotate`] method which rotates elements in the slice to the _left_ N positions. [Here][tracking] is the tracking issue for this unstable feature. ```rust let mut a = ['a', 'b' ,'c', 'd', 'e', 'f']; a.rotate(2); assert_eq!(a, ['c', 'd', 'e', 'f', 'a', 'b']); ``` Proposal ======== Deprecate the [`rotate`] method and introduce `rotate_left` and `rotate_right` methods. ```rust let mut a = ['a', 'b' ,'c', 'd', 'e', 'f']; a.rotate_left(2); assert_eq!(a, ['c', 'd', 'e', 'f', 'a', 'b']); ``` ```rust let mut a = ['a', 'b' ,'c', 'd', 'e', 'f']; a.rotate_right(2); assert_eq!(a, ['e', 'f', 'a', 'b', 'c', 'd']); ``` Justification ============= I used this method today for my first time and (probably because I’m a naive westerner who reads LTR) was surprised when the docs mentioned that elements get rotated in a left-ward direction. I was in a situation where I needed to shift elements in a right-ward direction and had to context switch from the main problem I was working on and think how much to rotate left in order to accomplish the right-ward rotation I needed. Ruby’s `Array.rotate` shifts left-ward, Python’s `deque.rotate` shifts right-ward. Both of their implementations allow passing negative numbers to shift in the opposite direction respectively. Introducing `rotate_left` and `rotate_right` would: - remove ambiguity about direction (alleviating need to read docs 😉) - make it easier for people who need to rotate right [`rotate`]: https://doc.rust-lang.org/std/primitive.slice.html#method.rotate [tracking]: https://github.com/rust-lang/rust/issues/41891
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v.rotate_left(expected.len());
assert_eq!(v, expected);
let mut zst_array = [(), (), ()];
Deprecate [T]::rotate in favor of [T]::rotate_{left,right}. Background ========== Slices currently have an unstable [`rotate`] method which rotates elements in the slice to the _left_ N positions. [Here][tracking] is the tracking issue for this unstable feature. ```rust let mut a = ['a', 'b' ,'c', 'd', 'e', 'f']; a.rotate(2); assert_eq!(a, ['c', 'd', 'e', 'f', 'a', 'b']); ``` Proposal ======== Deprecate the [`rotate`] method and introduce `rotate_left` and `rotate_right` methods. ```rust let mut a = ['a', 'b' ,'c', 'd', 'e', 'f']; a.rotate_left(2); assert_eq!(a, ['c', 'd', 'e', 'f', 'a', 'b']); ``` ```rust let mut a = ['a', 'b' ,'c', 'd', 'e', 'f']; a.rotate_right(2); assert_eq!(a, ['e', 'f', 'a', 'b', 'c', 'd']); ``` Justification ============= I used this method today for my first time and (probably because I’m a naive westerner who reads LTR) was surprised when the docs mentioned that elements get rotated in a left-ward direction. I was in a situation where I needed to shift elements in a right-ward direction and had to context switch from the main problem I was working on and think how much to rotate left in order to accomplish the right-ward rotation I needed. Ruby’s `Array.rotate` shifts left-ward, Python’s `deque.rotate` shifts right-ward. Both of their implementations allow passing negative numbers to shift in the opposite direction respectively. Introducing `rotate_left` and `rotate_right` would: - remove ambiguity about direction (alleviating need to read docs 😉) - make it easier for people who need to rotate right [`rotate`]: https://doc.rust-lang.org/std/primitive.slice.html#method.rotate [tracking]: https://github.com/rust-lang/rust/issues/41891
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zst_array.rotate_left(2);
// happy path
v = (5..13).chain(0..5).collect();
Deprecate [T]::rotate in favor of [T]::rotate_{left,right}. Background ========== Slices currently have an unstable [`rotate`] method which rotates elements in the slice to the _left_ N positions. [Here][tracking] is the tracking issue for this unstable feature. ```rust let mut a = ['a', 'b' ,'c', 'd', 'e', 'f']; a.rotate(2); assert_eq!(a, ['c', 'd', 'e', 'f', 'a', 'b']); ``` Proposal ======== Deprecate the [`rotate`] method and introduce `rotate_left` and `rotate_right` methods. ```rust let mut a = ['a', 'b' ,'c', 'd', 'e', 'f']; a.rotate_left(2); assert_eq!(a, ['c', 'd', 'e', 'f', 'a', 'b']); ``` ```rust let mut a = ['a', 'b' ,'c', 'd', 'e', 'f']; a.rotate_right(2); assert_eq!(a, ['e', 'f', 'a', 'b', 'c', 'd']); ``` Justification ============= I used this method today for my first time and (probably because I’m a naive westerner who reads LTR) was surprised when the docs mentioned that elements get rotated in a left-ward direction. I was in a situation where I needed to shift elements in a right-ward direction and had to context switch from the main problem I was working on and think how much to rotate left in order to accomplish the right-ward rotation I needed. Ruby’s `Array.rotate` shifts left-ward, Python’s `deque.rotate` shifts right-ward. Both of their implementations allow passing negative numbers to shift in the opposite direction respectively. Introducing `rotate_left` and `rotate_right` would: - remove ambiguity about direction (alleviating need to read docs 😉) - make it easier for people who need to rotate right [`rotate`]: https://doc.rust-lang.org/std/primitive.slice.html#method.rotate [tracking]: https://github.com/rust-lang/rust/issues/41891
2017-12-16 14:29:09 -06:00
v.rotate_left(8);
assert_eq!(v, expected);
let expected: Vec<_> = (0..1000).collect();
// small rotations in large slice, uses ptr::copy
v = (2..1000).chain(0..2).collect();
Deprecate [T]::rotate in favor of [T]::rotate_{left,right}. Background ========== Slices currently have an unstable [`rotate`] method which rotates elements in the slice to the _left_ N positions. [Here][tracking] is the tracking issue for this unstable feature. ```rust let mut a = ['a', 'b' ,'c', 'd', 'e', 'f']; a.rotate(2); assert_eq!(a, ['c', 'd', 'e', 'f', 'a', 'b']); ``` Proposal ======== Deprecate the [`rotate`] method and introduce `rotate_left` and `rotate_right` methods. ```rust let mut a = ['a', 'b' ,'c', 'd', 'e', 'f']; a.rotate_left(2); assert_eq!(a, ['c', 'd', 'e', 'f', 'a', 'b']); ``` ```rust let mut a = ['a', 'b' ,'c', 'd', 'e', 'f']; a.rotate_right(2); assert_eq!(a, ['e', 'f', 'a', 'b', 'c', 'd']); ``` Justification ============= I used this method today for my first time and (probably because I’m a naive westerner who reads LTR) was surprised when the docs mentioned that elements get rotated in a left-ward direction. I was in a situation where I needed to shift elements in a right-ward direction and had to context switch from the main problem I was working on and think how much to rotate left in order to accomplish the right-ward rotation I needed. Ruby’s `Array.rotate` shifts left-ward, Python’s `deque.rotate` shifts right-ward. Both of their implementations allow passing negative numbers to shift in the opposite direction respectively. Introducing `rotate_left` and `rotate_right` would: - remove ambiguity about direction (alleviating need to read docs 😉) - make it easier for people who need to rotate right [`rotate`]: https://doc.rust-lang.org/std/primitive.slice.html#method.rotate [tracking]: https://github.com/rust-lang/rust/issues/41891
2017-12-16 14:29:09 -06:00
v.rotate_left(998);
assert_eq!(v, expected);
v = (998..1000).chain(0..998).collect();
Deprecate [T]::rotate in favor of [T]::rotate_{left,right}. Background ========== Slices currently have an unstable [`rotate`] method which rotates elements in the slice to the _left_ N positions. [Here][tracking] is the tracking issue for this unstable feature. ```rust let mut a = ['a', 'b' ,'c', 'd', 'e', 'f']; a.rotate(2); assert_eq!(a, ['c', 'd', 'e', 'f', 'a', 'b']); ``` Proposal ======== Deprecate the [`rotate`] method and introduce `rotate_left` and `rotate_right` methods. ```rust let mut a = ['a', 'b' ,'c', 'd', 'e', 'f']; a.rotate_left(2); assert_eq!(a, ['c', 'd', 'e', 'f', 'a', 'b']); ``` ```rust let mut a = ['a', 'b' ,'c', 'd', 'e', 'f']; a.rotate_right(2); assert_eq!(a, ['e', 'f', 'a', 'b', 'c', 'd']); ``` Justification ============= I used this method today for my first time and (probably because I’m a naive westerner who reads LTR) was surprised when the docs mentioned that elements get rotated in a left-ward direction. I was in a situation where I needed to shift elements in a right-ward direction and had to context switch from the main problem I was working on and think how much to rotate left in order to accomplish the right-ward rotation I needed. Ruby’s `Array.rotate` shifts left-ward, Python’s `deque.rotate` shifts right-ward. Both of their implementations allow passing negative numbers to shift in the opposite direction respectively. Introducing `rotate_left` and `rotate_right` would: - remove ambiguity about direction (alleviating need to read docs 😉) - make it easier for people who need to rotate right [`rotate`]: https://doc.rust-lang.org/std/primitive.slice.html#method.rotate [tracking]: https://github.com/rust-lang/rust/issues/41891
2017-12-16 14:29:09 -06:00
v.rotate_left(2);
assert_eq!(v, expected);
// non-small prime rotation, has a few rounds of swapping
v = (389..1000).chain(0..389).collect();
Deprecate [T]::rotate in favor of [T]::rotate_{left,right}. Background ========== Slices currently have an unstable [`rotate`] method which rotates elements in the slice to the _left_ N positions. [Here][tracking] is the tracking issue for this unstable feature. ```rust let mut a = ['a', 'b' ,'c', 'd', 'e', 'f']; a.rotate(2); assert_eq!(a, ['c', 'd', 'e', 'f', 'a', 'b']); ``` Proposal ======== Deprecate the [`rotate`] method and introduce `rotate_left` and `rotate_right` methods. ```rust let mut a = ['a', 'b' ,'c', 'd', 'e', 'f']; a.rotate_left(2); assert_eq!(a, ['c', 'd', 'e', 'f', 'a', 'b']); ``` ```rust let mut a = ['a', 'b' ,'c', 'd', 'e', 'f']; a.rotate_right(2); assert_eq!(a, ['e', 'f', 'a', 'b', 'c', 'd']); ``` Justification ============= I used this method today for my first time and (probably because I’m a naive westerner who reads LTR) was surprised when the docs mentioned that elements get rotated in a left-ward direction. I was in a situation where I needed to shift elements in a right-ward direction and had to context switch from the main problem I was working on and think how much to rotate left in order to accomplish the right-ward rotation I needed. Ruby’s `Array.rotate` shifts left-ward, Python’s `deque.rotate` shifts right-ward. Both of their implementations allow passing negative numbers to shift in the opposite direction respectively. Introducing `rotate_left` and `rotate_right` would: - remove ambiguity about direction (alleviating need to read docs 😉) - make it easier for people who need to rotate right [`rotate`]: https://doc.rust-lang.org/std/primitive.slice.html#method.rotate [tracking]: https://github.com/rust-lang/rust/issues/41891
2017-12-16 14:29:09 -06:00
v.rotate_left(1000-389);
assert_eq!(v, expected);
}
#[test]
fn test_rotate_right() {
let expected: Vec<_> = (0..13).collect();
let mut v = Vec::new();
// no-ops
v.clone_from(&expected);
v.rotate_right(0);
assert_eq!(v, expected);
v.rotate_right(expected.len());
assert_eq!(v, expected);
let mut zst_array = [(), (), ()];
zst_array.rotate_right(2);
// happy path
v = (5..13).chain(0..5).collect();
v.rotate_right(5);
assert_eq!(v, expected);
let expected: Vec<_> = (0..1000).collect();
// small rotations in large slice, uses ptr::copy
v = (2..1000).chain(0..2).collect();
v.rotate_right(2);
assert_eq!(v, expected);
v = (998..1000).chain(0..998).collect();
v.rotate_right(998);
assert_eq!(v, expected);
// non-small prime rotation, has a few rounds of swapping
v = (389..1000).chain(0..389).collect();
v.rotate_right(389);
assert_eq!(v, expected);
}
#[test]
fn test_concat() {
let v: [Vec<i32>; 0] = [];
let c = v.concat();
assert_eq!(c, []);
let d = [vec![1], vec![2, 3]].concat();
assert_eq!(d, [1, 2, 3]);
let v: &[&[_]] = &[&[1], &[2, 3]];
assert_eq!(v.join(&0), [1, 0, 2, 3]);
let v: &[&[_]] = &[&[1], &[2], &[3]];
assert_eq!(v.join(&0), [1, 0, 2, 0, 3]);
}
#[test]
fn test_join() {
let v: [Vec<i32>; 0] = [];
assert_eq!(v.join(&0), []);
assert_eq!([vec![1], vec![2, 3]].join(&0), [1, 0, 2, 3]);
assert_eq!([vec![1], vec![2], vec![3]].join(&0), [1, 0, 2, 0, 3]);
let v: [&[_]; 2] = [&[1], &[2, 3]];
assert_eq!(v.join(&0), [1, 0, 2, 3]);
let v: [&[_]; 3] = [&[1], &[2], &[3]];
assert_eq!(v.join(&0), [1, 0, 2, 0, 3]);
}
#[test]
fn test_join_nocopy() {
let v: [String; 0] = [];
assert_eq!(v.join(","), "");
assert_eq!(["a".to_string(), "ab".into()].join(","), "a,ab");
assert_eq!(["a".to_string(), "ab".into(), "abc".into()].join(","), "a,ab,abc");
assert_eq!(["a".to_string(), "ab".into(), "".into()].join(","), "a,ab,");
}
#[test]
fn test_insert() {
let mut a = vec![1, 2, 4];
a.insert(2, 3);
assert_eq!(a, [1, 2, 3, 4]);
let mut a = vec![1, 2, 3];
a.insert(0, 0);
assert_eq!(a, [0, 1, 2, 3]);
let mut a = vec![1, 2, 3];
a.insert(3, 4);
assert_eq!(a, [1, 2, 3, 4]);
let mut a = vec![];
a.insert(0, 1);
assert_eq!(a, [1]);
}
#[test]
#[should_panic]
fn test_insert_oob() {
let mut a = vec![1, 2, 3];
a.insert(4, 5);
}
#[test]
fn test_remove() {
let mut a = vec![1, 2, 3, 4];
assert_eq!(a.remove(2), 3);
assert_eq!(a, [1, 2, 4]);
assert_eq!(a.remove(2), 4);
assert_eq!(a, [1, 2]);
assert_eq!(a.remove(0), 1);
assert_eq!(a, [2]);
assert_eq!(a.remove(0), 2);
assert_eq!(a, []);
}
#[test]
#[should_panic]
fn test_remove_fail() {
let mut a = vec![1];
let _ = a.remove(0);
let _ = a.remove(0);
}
#[test]
fn test_capacity() {
let mut v = vec![0];
v.reserve_exact(10);
assert!(v.capacity() >= 11);
}
#[test]
fn test_slice_2() {
let v = vec![1, 2, 3, 4, 5];
let v = &v[1..3];
assert_eq!(v.len(), 2);
assert_eq!(v[0], 2);
assert_eq!(v[1], 3);
}
macro_rules! assert_order {
(Greater, $a:expr, $b:expr) => {
assert_eq!($a.cmp($b), Greater);
assert!($a > $b);
};
(Less, $a:expr, $b:expr) => {
assert_eq!($a.cmp($b), Less);
assert!($a < $b);
};
(Equal, $a:expr, $b:expr) => {
assert_eq!($a.cmp($b), Equal);
assert_eq!($a, $b);
}
}
#[test]
fn test_total_ord_u8() {
let c = &[1u8, 2, 3];
assert_order!(Greater, &[1u8, 2, 3, 4][..], &c[..]);
let c = &[1u8, 2, 3, 4];
assert_order!(Less, &[1u8, 2, 3][..], &c[..]);
let c = &[1u8, 2, 3, 6];
assert_order!(Equal, &[1u8, 2, 3, 6][..], &c[..]);
let c = &[1u8, 2, 3, 4, 5, 6];
assert_order!(Less, &[1u8, 2, 3, 4, 5, 5, 5, 5][..], &c[..]);
let c = &[1u8, 2, 3, 4];
assert_order!(Greater, &[2u8, 2][..], &c[..]);
}
#[test]
fn test_total_ord_i32() {
let c = &[1, 2, 3];
assert_order!(Greater, &[1, 2, 3, 4][..], &c[..]);
let c = &[1, 2, 3, 4];
assert_order!(Less, &[1, 2, 3][..], &c[..]);
let c = &[1, 2, 3, 6];
assert_order!(Equal, &[1, 2, 3, 6][..], &c[..]);
let c = &[1, 2, 3, 4, 5, 6];
assert_order!(Less, &[1, 2, 3, 4, 5, 5, 5, 5][..], &c[..]);
let c = &[1, 2, 3, 4];
assert_order!(Greater, &[2, 2][..], &c[..]);
}
#[test]
fn test_iterator() {
let xs = [1, 2, 5, 10, 11];
let mut it = xs.iter();
assert_eq!(it.size_hint(), (5, Some(5)));
assert_eq!(it.next().unwrap(), &1);
assert_eq!(it.size_hint(), (4, Some(4)));
assert_eq!(it.next().unwrap(), &2);
assert_eq!(it.size_hint(), (3, Some(3)));
assert_eq!(it.next().unwrap(), &5);
assert_eq!(it.size_hint(), (2, Some(2)));
assert_eq!(it.next().unwrap(), &10);
assert_eq!(it.size_hint(), (1, Some(1)));
assert_eq!(it.next().unwrap(), &11);
assert_eq!(it.size_hint(), (0, Some(0)));
assert!(it.next().is_none());
}
#[test]
fn test_iter_size_hints() {
let mut xs = [1, 2, 5, 10, 11];
assert_eq!(xs.iter().size_hint(), (5, Some(5)));
assert_eq!(xs.iter_mut().size_hint(), (5, Some(5)));
}
#[test]
fn test_iter_as_slice() {
let xs = [1, 2, 5, 10, 11];
let mut iter = xs.iter();
assert_eq!(iter.as_slice(), &[1, 2, 5, 10, 11]);
iter.next();
assert_eq!(iter.as_slice(), &[2, 5, 10, 11]);
}
#[test]
fn test_iter_as_ref() {
let xs = [1, 2, 5, 10, 11];
let mut iter = xs.iter();
assert_eq!(iter.as_ref(), &[1, 2, 5, 10, 11]);
iter.next();
assert_eq!(iter.as_ref(), &[2, 5, 10, 11]);
}
#[test]
fn test_iter_clone() {
let xs = [1, 2, 5];
let mut it = xs.iter();
it.next();
let mut jt = it.clone();
assert_eq!(it.next(), jt.next());
assert_eq!(it.next(), jt.next());
assert_eq!(it.next(), jt.next());
}
#[test]
fn test_iter_is_empty() {
let xs = [1, 2, 5, 10, 11];
for i in 0..xs.len() {
for j in i..xs.len() {
assert_eq!(xs[i..j].iter().is_empty(), xs[i..j].is_empty());
}
}
}
#[test]
fn test_mut_iterator() {
let mut xs = [1, 2, 3, 4, 5];
for x in &mut xs {
*x += 1;
}
assert!(xs == [2, 3, 4, 5, 6])
}
#[test]
fn test_rev_iterator() {
let xs = [1, 2, 5, 10, 11];
let ys = [11, 10, 5, 2, 1];
let mut i = 0;
for &x in xs.iter().rev() {
assert_eq!(x, ys[i]);
i += 1;
}
assert_eq!(i, 5);
}
#[test]
fn test_mut_rev_iterator() {
let mut xs = [1, 2, 3, 4, 5];
for (i, x) in xs.iter_mut().rev().enumerate() {
*x += i;
}
assert!(xs == [5, 5, 5, 5, 5])
}
#[test]
fn test_move_iterator() {
let xs = vec![1, 2, 3, 4, 5];
assert_eq!(xs.into_iter().fold(0, |a: usize, b: usize| 10 * a + b),
12345);
}
#[test]
fn test_move_rev_iterator() {
let xs = vec![1, 2, 3, 4, 5];
assert_eq!(xs.into_iter().rev().fold(0, |a: usize, b: usize| 10 * a + b),
54321);
}
#[test]
fn test_splitator() {
let xs = &[1, 2, 3, 4, 5];
let splits: &[&[_]] = &[&[1], &[3], &[5]];
assert_eq!(xs.split(|x| *x % 2 == 0).collect::<Vec<_>>(), splits);
let splits: &[&[_]] = &[&[], &[2, 3, 4, 5]];
assert_eq!(xs.split(|x| *x == 1).collect::<Vec<_>>(), splits);
let splits: &[&[_]] = &[&[1, 2, 3, 4], &[]];
assert_eq!(xs.split(|x| *x == 5).collect::<Vec<_>>(), splits);
let splits: &[&[_]] = &[&[1, 2, 3, 4, 5]];
assert_eq!(xs.split(|x| *x == 10).collect::<Vec<_>>(), splits);
let splits: &[&[_]] = &[&[], &[], &[], &[], &[], &[]];
assert_eq!(xs.split(|_| true).collect::<Vec<&[i32]>>(), splits);
let xs: &[i32] = &[];
let splits: &[&[i32]] = &[&[]];
assert_eq!(xs.split(|x| *x == 5).collect::<Vec<&[i32]>>(), splits);
}
#[test]
fn test_splitnator() {
let xs = &[1, 2, 3, 4, 5];
let splits: &[&[_]] = &[&[1, 2, 3, 4, 5]];
assert_eq!(xs.splitn(1, |x| *x % 2 == 0).collect::<Vec<_>>(), splits);
let splits: &[&[_]] = &[&[1], &[3, 4, 5]];
assert_eq!(xs.splitn(2, |x| *x % 2 == 0).collect::<Vec<_>>(), splits);
let splits: &[&[_]] = &[&[], &[], &[], &[4, 5]];
assert_eq!(xs.splitn(4, |_| true).collect::<Vec<_>>(), splits);
let xs: &[i32] = &[];
let splits: &[&[i32]] = &[&[]];
assert_eq!(xs.splitn(2, |x| *x == 5).collect::<Vec<_>>(), splits);
}
#[test]
fn test_splitnator_mut() {
let xs = &mut [1, 2, 3, 4, 5];
let splits: &[&mut [_]] = &[&mut [1, 2, 3, 4, 5]];
assert_eq!(xs.splitn_mut(1, |x| *x % 2 == 0).collect::<Vec<_>>(),
splits);
let splits: &[&mut [_]] = &[&mut [1], &mut [3, 4, 5]];
assert_eq!(xs.splitn_mut(2, |x| *x % 2 == 0).collect::<Vec<_>>(),
splits);
let splits: &[&mut [_]] = &[&mut [], &mut [], &mut [], &mut [4, 5]];
assert_eq!(xs.splitn_mut(4, |_| true).collect::<Vec<_>>(), splits);
let xs: &mut [i32] = &mut [];
let splits: &[&mut [i32]] = &[&mut []];
assert_eq!(xs.splitn_mut(2, |x| *x == 5).collect::<Vec<_>>(), splits);
}
#[test]
fn test_rsplitator() {
let xs = &[1, 2, 3, 4, 5];
let splits: &[&[_]] = &[&[5], &[3], &[1]];
assert_eq!(xs.split(|x| *x % 2 == 0).rev().collect::<Vec<_>>(), splits);
let splits: &[&[_]] = &[&[2, 3, 4, 5], &[]];
assert_eq!(xs.split(|x| *x == 1).rev().collect::<Vec<_>>(), splits);
let splits: &[&[_]] = &[&[], &[1, 2, 3, 4]];
assert_eq!(xs.split(|x| *x == 5).rev().collect::<Vec<_>>(), splits);
let splits: &[&[_]] = &[&[1, 2, 3, 4, 5]];
assert_eq!(xs.split(|x| *x == 10).rev().collect::<Vec<_>>(), splits);
let xs: &[i32] = &[];
let splits: &[&[i32]] = &[&[]];
assert_eq!(xs.split(|x| *x == 5).rev().collect::<Vec<&[i32]>>(), splits);
}
#[test]
fn test_rsplitnator() {
let xs = &[1, 2, 3, 4, 5];
let splits: &[&[_]] = &[&[1, 2, 3, 4, 5]];
assert_eq!(xs.rsplitn(1, |x| *x % 2 == 0).collect::<Vec<_>>(), splits);
let splits: &[&[_]] = &[&[5], &[1, 2, 3]];
assert_eq!(xs.rsplitn(2, |x| *x % 2 == 0).collect::<Vec<_>>(), splits);
let splits: &[&[_]] = &[&[], &[], &[], &[1, 2]];
assert_eq!(xs.rsplitn(4, |_| true).collect::<Vec<_>>(), splits);
let xs: &[i32] = &[];
let splits: &[&[i32]] = &[&[]];
assert_eq!(xs.rsplitn(2, |x| *x == 5).collect::<Vec<&[i32]>>(), splits);
assert!(xs.rsplitn(0, |x| *x % 2 == 0).next().is_none());
}
#[test]
fn test_windowsator() {
let v = &[1, 2, 3, 4];
let wins: &[&[_]] = &[&[1, 2], &[2, 3], &[3, 4]];
assert_eq!(v.windows(2).collect::<Vec<_>>(), wins);
let wins: &[&[_]] = &[&[1, 2, 3], &[2, 3, 4]];
assert_eq!(v.windows(3).collect::<Vec<_>>(), wins);
assert!(v.windows(6).next().is_none());
let wins: &[&[_]] = &[&[3, 4], &[2, 3], &[1, 2]];
assert_eq!(v.windows(2).rev().collect::<Vec<&[_]>>(), wins);
}
#[test]
#[should_panic]
fn test_windowsator_0() {
let v = &[1, 2, 3, 4];
let _it = v.windows(0);
}
#[test]
fn test_chunksator() {
let v = &[1, 2, 3, 4, 5];
assert_eq!(v.chunks(2).len(), 3);
let chunks: &[&[_]] = &[&[1, 2], &[3, 4], &[5]];
assert_eq!(v.chunks(2).collect::<Vec<_>>(), chunks);
let chunks: &[&[_]] = &[&[1, 2, 3], &[4, 5]];
assert_eq!(v.chunks(3).collect::<Vec<_>>(), chunks);
let chunks: &[&[_]] = &[&[1, 2, 3, 4, 5]];
assert_eq!(v.chunks(6).collect::<Vec<_>>(), chunks);
let chunks: &[&[_]] = &[&[5], &[3, 4], &[1, 2]];
assert_eq!(v.chunks(2).rev().collect::<Vec<_>>(), chunks);
}
#[test]
#[should_panic]
fn test_chunksator_0() {
let v = &[1, 2, 3, 4];
let _it = v.chunks(0);
}
#[test]
fn test_chunks_exactator() {
let v = &[1, 2, 3, 4, 5];
assert_eq!(v.chunks_exact(2).len(), 2);
let chunks: &[&[_]] = &[&[1, 2], &[3, 4]];
assert_eq!(v.chunks_exact(2).collect::<Vec<_>>(), chunks);
let chunks: &[&[_]] = &[&[1, 2, 3]];
assert_eq!(v.chunks_exact(3).collect::<Vec<_>>(), chunks);
let chunks: &[&[_]] = &[];
assert_eq!(v.chunks_exact(6).collect::<Vec<_>>(), chunks);
let chunks: &[&[_]] = &[&[3, 4], &[1, 2]];
assert_eq!(v.chunks_exact(2).rev().collect::<Vec<_>>(), chunks);
}
#[test]
#[should_panic]
fn test_chunks_exactator_0() {
let v = &[1, 2, 3, 4];
let _it = v.chunks_exact(0);
}
#[test]
fn test_rchunksator() {
let v = &[1, 2, 3, 4, 5];
assert_eq!(v.rchunks(2).len(), 3);
let chunks: &[&[_]] = &[&[4, 5], &[2, 3], &[1]];
assert_eq!(v.rchunks(2).collect::<Vec<_>>(), chunks);
let chunks: &[&[_]] = &[&[3, 4, 5], &[1, 2]];
assert_eq!(v.rchunks(3).collect::<Vec<_>>(), chunks);
let chunks: &[&[_]] = &[&[1, 2, 3, 4, 5]];
assert_eq!(v.rchunks(6).collect::<Vec<_>>(), chunks);
let chunks: &[&[_]] = &[&[1], &[2, 3], &[4, 5]];
assert_eq!(v.rchunks(2).rev().collect::<Vec<_>>(), chunks);
}
#[test]
#[should_panic]
fn test_rchunksator_0() {
let v = &[1, 2, 3, 4];
let _it = v.rchunks(0);
}
#[test]
fn test_rchunks_exactator() {
let v = &[1, 2, 3, 4, 5];
assert_eq!(v.rchunks_exact(2).len(), 2);
let chunks: &[&[_]] = &[&[4, 5], &[2, 3]];
assert_eq!(v.rchunks_exact(2).collect::<Vec<_>>(), chunks);
let chunks: &[&[_]] = &[&[3, 4, 5]];
assert_eq!(v.rchunks_exact(3).collect::<Vec<_>>(), chunks);
let chunks: &[&[_]] = &[];
assert_eq!(v.rchunks_exact(6).collect::<Vec<_>>(), chunks);
let chunks: &[&[_]] = &[&[2, 3], &[4, 5]];
assert_eq!(v.rchunks_exact(2).rev().collect::<Vec<_>>(), chunks);
}
#[test]
#[should_panic]
fn test_rchunks_exactator_0() {
let v = &[1, 2, 3, 4];
let _it = v.rchunks_exact(0);
}
#[test]
fn test_reverse_part() {
let mut values = [1, 2, 3, 4, 5];
values[1..4].reverse();
assert!(values == [1, 4, 3, 2, 5]);
}
#[test]
fn test_show() {
macro_rules! test_show_vec {
($x:expr, $x_str:expr) => ({
let (x, x_str) = ($x, $x_str);
assert_eq!(format!("{:?}", x), x_str);
assert_eq!(format!("{:?}", x), x_str);
})
}
let empty = Vec::<i32>::new();
test_show_vec!(empty, "[]");
test_show_vec!(vec![1], "[1]");
test_show_vec!(vec![1, 2, 3], "[1, 2, 3]");
test_show_vec!(vec![vec![], vec![1], vec![1, 1]], "[[], [1], [1, 1]]");
let empty_mut: &mut [i32] = &mut [];
test_show_vec!(empty_mut, "[]");
let v = &mut [1];
test_show_vec!(v, "[1]");
let v = &mut [1, 2, 3];
test_show_vec!(v, "[1, 2, 3]");
let v: &mut [&mut [_]] = &mut [&mut [], &mut [1], &mut [1, 1]];
test_show_vec!(v, "[[], [1], [1, 1]]");
}
#[test]
fn test_vec_default() {
macro_rules! t {
($ty:ty) => {{
let v: $ty = Default::default();
assert!(v.is_empty());
}}
}
t!(&[i32]);
t!(Vec<i32>);
}
#[test]
#[should_panic]
fn test_overflow_does_not_cause_segfault() {
let mut v = vec![];
v.reserve_exact(!0);
v.push(1);
v.push(2);
}
#[test]
#[should_panic]
fn test_overflow_does_not_cause_segfault_managed() {
let mut v = vec![Rc::new(1)];
v.reserve_exact(!0);
v.push(Rc::new(2));
}
#[test]
fn test_mut_split_at() {
let mut values = [1, 2, 3, 4, 5];
{
let (left, right) = values.split_at_mut(2);
{
let left: &[_] = left;
assert!(left[..left.len()] == [1, 2]);
}
for p in left {
*p += 1;
}
{
let right: &[_] = right;
assert!(right[..right.len()] == [3, 4, 5]);
}
for p in right {
*p += 2;
}
}
assert!(values == [2, 3, 5, 6, 7]);
}
#[derive(Clone, PartialEq)]
struct Foo;
#[test]
fn test_iter_zero_sized() {
let mut v = vec![Foo, Foo, Foo];
assert_eq!(v.len(), 3);
let mut cnt = 0;
for f in &v {
assert!(*f == Foo);
cnt += 1;
}
assert_eq!(cnt, 3);
for f in &v[1..3] {
assert!(*f == Foo);
cnt += 1;
}
assert_eq!(cnt, 5);
for f in &mut v {
assert!(*f == Foo);
cnt += 1;
}
assert_eq!(cnt, 8);
for f in v {
assert!(f == Foo);
cnt += 1;
}
assert_eq!(cnt, 11);
let xs: [Foo; 3] = [Foo, Foo, Foo];
cnt = 0;
for f in &xs {
assert!(*f == Foo);
cnt += 1;
}
assert!(cnt == 3);
}
#[test]
fn test_shrink_to_fit() {
let mut xs = vec![0, 1, 2, 3];
for i in 4..100 {
xs.push(i)
}
assert_eq!(xs.capacity(), 128);
xs.shrink_to_fit();
assert_eq!(xs.capacity(), 100);
assert_eq!(xs, (0..100).collect::<Vec<_>>());
}
#[test]
fn test_starts_with() {
assert!(b"foobar".starts_with(b"foo"));
assert!(!b"foobar".starts_with(b"oob"));
assert!(!b"foobar".starts_with(b"bar"));
assert!(!b"foo".starts_with(b"foobar"));
assert!(!b"bar".starts_with(b"foobar"));
assert!(b"foobar".starts_with(b"foobar"));
let empty: &[u8] = &[];
assert!(empty.starts_with(empty));
assert!(!empty.starts_with(b"foo"));
assert!(b"foobar".starts_with(empty));
}
#[test]
fn test_ends_with() {
assert!(b"foobar".ends_with(b"bar"));
assert!(!b"foobar".ends_with(b"oba"));
assert!(!b"foobar".ends_with(b"foo"));
assert!(!b"foo".ends_with(b"foobar"));
assert!(!b"bar".ends_with(b"foobar"));
assert!(b"foobar".ends_with(b"foobar"));
let empty: &[u8] = &[];
assert!(empty.ends_with(empty));
assert!(!empty.ends_with(b"foo"));
assert!(b"foobar".ends_with(empty));
}
#[test]
fn test_mut_splitator() {
let mut xs = [0, 1, 0, 2, 3, 0, 0, 4, 5, 0];
assert_eq!(xs.split_mut(|x| *x == 0).count(), 6);
for slice in xs.split_mut(|x| *x == 0) {
slice.reverse();
}
assert!(xs == [0, 1, 0, 3, 2, 0, 0, 5, 4, 0]);
let mut xs = [0, 1, 0, 2, 3, 0, 0, 4, 5, 0, 6, 7];
for slice in xs.split_mut(|x| *x == 0).take(5) {
slice.reverse();
}
assert!(xs == [0, 1, 0, 3, 2, 0, 0, 5, 4, 0, 6, 7]);
}
#[test]
fn test_mut_splitator_rev() {
let mut xs = [1, 2, 0, 3, 4, 0, 0, 5, 6, 0];
for slice in xs.split_mut(|x| *x == 0).rev().take(4) {
slice.reverse();
}
assert!(xs == [1, 2, 0, 4, 3, 0, 0, 6, 5, 0]);
}
#[test]
fn test_get_mut() {
let mut v = [0, 1, 2];
assert_eq!(v.get_mut(3), None);
v.get_mut(1).map(|e| *e = 7);
assert_eq!(v[1], 7);
let mut x = 2;
assert_eq!(v.get_mut(2), Some(&mut x));
}
#[test]
fn test_mut_chunks() {
let mut v = [0, 1, 2, 3, 4, 5, 6];
assert_eq!(v.chunks_mut(3).len(), 3);
for (i, chunk) in v.chunks_mut(3).enumerate() {
for x in chunk {
*x = i as u8;
}
}
let result = [0, 0, 0, 1, 1, 1, 2];
assert_eq!(v, result);
}
#[test]
fn test_mut_chunks_rev() {
let mut v = [0, 1, 2, 3, 4, 5, 6];
for (i, chunk) in v.chunks_mut(3).rev().enumerate() {
for x in chunk {
*x = i as u8;
}
}
let result = [2, 2, 2, 1, 1, 1, 0];
assert_eq!(v, result);
}
#[test]
#[should_panic]
fn test_mut_chunks_0() {
let mut v = [1, 2, 3, 4];
let _it = v.chunks_mut(0);
}
#[test]
fn test_mut_chunks_exact() {
let mut v = [0, 1, 2, 3, 4, 5, 6];
assert_eq!(v.chunks_exact_mut(3).len(), 2);
for (i, chunk) in v.chunks_exact_mut(3).enumerate() {
for x in chunk {
*x = i as u8;
}
}
let result = [0, 0, 0, 1, 1, 1, 6];
assert_eq!(v, result);
}
#[test]
fn test_mut_chunks_exact_rev() {
let mut v = [0, 1, 2, 3, 4, 5, 6];
for (i, chunk) in v.chunks_exact_mut(3).rev().enumerate() {
for x in chunk {
*x = i as u8;
}
}
let result = [1, 1, 1, 0, 0, 0, 6];
assert_eq!(v, result);
}
#[test]
#[should_panic]
fn test_mut_chunks_exact_0() {
let mut v = [1, 2, 3, 4];
let _it = v.chunks_exact_mut(0);
}
#[test]
fn test_mut_rchunks() {
let mut v = [0, 1, 2, 3, 4, 5, 6];
assert_eq!(v.rchunks_mut(3).len(), 3);
for (i, chunk) in v.rchunks_mut(3).enumerate() {
for x in chunk {
*x = i as u8;
}
}
let result = [2, 1, 1, 1, 0, 0, 0];
assert_eq!(v, result);
}
#[test]
fn test_mut_rchunks_rev() {
let mut v = [0, 1, 2, 3, 4, 5, 6];
for (i, chunk) in v.rchunks_mut(3).rev().enumerate() {
for x in chunk {
*x = i as u8;
}
}
let result = [0, 1, 1, 1, 2, 2, 2];
assert_eq!(v, result);
}
#[test]
#[should_panic]
fn test_mut_rchunks_0() {
let mut v = [1, 2, 3, 4];
let _it = v.rchunks_mut(0);
}
#[test]
fn test_mut_rchunks_exact() {
let mut v = [0, 1, 2, 3, 4, 5, 6];
assert_eq!(v.rchunks_exact_mut(3).len(), 2);
for (i, chunk) in v.rchunks_exact_mut(3).enumerate() {
for x in chunk {
*x = i as u8;
}
}
let result = [0, 1, 1, 1, 0, 0, 0];
assert_eq!(v, result);
}
#[test]
fn test_mut_rchunks_exact_rev() {
let mut v = [0, 1, 2, 3, 4, 5, 6];
for (i, chunk) in v.rchunks_exact_mut(3).rev().enumerate() {
for x in chunk {
*x = i as u8;
}
}
let result = [0, 0, 0, 0, 1, 1, 1];
assert_eq!(v, result);
}
#[test]
#[should_panic]
fn test_mut_rchunks_exact_0() {
let mut v = [1, 2, 3, 4];
let _it = v.rchunks_exact_mut(0);
}
#[test]
fn test_mut_last() {
let mut x = [1, 2, 3, 4, 5];
let h = x.last_mut();
assert_eq!(*h.unwrap(), 5);
let y: &mut [i32] = &mut [];
assert!(y.last_mut().is_none());
}
#[test]
fn test_to_vec() {
let xs: Box<_> = box [1, 2, 3];
let ys = xs.to_vec();
assert_eq!(ys, [1, 2, 3]);
}
#[test]
fn test_box_slice_clone() {
let data = vec![vec![0, 1], vec![0], vec![1]];
let data2 = data.clone().into_boxed_slice().clone().to_vec();
assert_eq!(data, data2);
}
#[test]
#[allow(unused_must_use)] // here, we care about the side effects of `.clone()`
#[cfg_attr(target_os = "emscripten", ignore)]
fn test_box_slice_clone_panics() {
use std::sync::Arc;
use std::sync::atomic::{AtomicUsize, Ordering};
use std::thread::spawn;
struct Canary {
count: Arc<AtomicUsize>,
panics: bool,
}
impl Drop for Canary {
fn drop(&mut self) {
self.count.fetch_add(1, Ordering::SeqCst);
}
}
impl Clone for Canary {
fn clone(&self) -> Self {
if self.panics {
panic!()
}
Canary {
count: self.count.clone(),
panics: self.panics,
}
}
}
let drop_count = Arc::new(AtomicUsize::new(0));
let canary = Canary {
count: drop_count.clone(),
panics: false,
};
let panic = Canary {
count: drop_count.clone(),
panics: true,
};
spawn(move || {
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// When xs is dropped, +5.
let xs = vec![canary.clone(), canary.clone(), canary.clone(), panic, canary]
.into_boxed_slice();
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// When panic is cloned, +3.
xs.clone();
})
.join()
.unwrap_err();
// Total = 8
assert_eq!(drop_count.load(Ordering::SeqCst), 8);
}
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#[test]
fn test_copy_from_slice() {
let src = [0, 1, 2, 3, 4, 5];
let mut dst = [0; 6];
dst.copy_from_slice(&src);
assert_eq!(src, dst)
}
#[test]
#[should_panic(expected = "destination and source slices have different lengths")]
fn test_copy_from_slice_dst_longer() {
let src = [0, 1, 2, 3];
let mut dst = [0; 5];
dst.copy_from_slice(&src);
}
#[test]
#[should_panic(expected = "destination and source slices have different lengths")]
fn test_copy_from_slice_dst_shorter() {
let src = [0, 1, 2, 3];
let mut dst = [0; 3];
dst.copy_from_slice(&src);
}
const MAX_LEN: usize = 80;
static DROP_COUNTS: [AtomicUsize; MAX_LEN] = [
// FIXME(RFC 1109): AtomicUsize is not Copy.
AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0),
AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0),
AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0),
AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0),
AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0),
AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0),
AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0),
AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0),
AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0),
AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0),
AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0),
AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0),
AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0),
AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0),
AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0),
AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0),
AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0),
AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0),
AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0),
AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0), AtomicUsize::new(0),
];
static VERSIONS: AtomicUsize = ATOMIC_USIZE_INIT;
#[derive(Clone, Eq)]
struct DropCounter {
x: u32,
id: usize,
version: Cell<usize>,
}
impl PartialEq for DropCounter {
fn eq(&self, other: &Self) -> bool {
self.partial_cmp(other) == Some(Ordering::Equal)
}
}
impl PartialOrd for DropCounter {
fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
self.version.set(self.version.get() + 1);
other.version.set(other.version.get() + 1);
VERSIONS.fetch_add(2, Relaxed);
self.x.partial_cmp(&other.x)
}
}
impl Ord for DropCounter {
fn cmp(&self, other: &Self) -> Ordering {
self.partial_cmp(other).unwrap()
}
}
impl Drop for DropCounter {
fn drop(&mut self) {
DROP_COUNTS[self.id].fetch_add(1, Relaxed);
VERSIONS.fetch_sub(self.version.get(), Relaxed);
}
}
macro_rules! test {
($input:ident, $func:ident) => {
let len = $input.len();
// Work out the total number of comparisons required to sort
// this array...
let mut count = 0usize;
$input.to_owned().$func(|a, b| { count += 1; a.cmp(b) });
// ... and then panic on each and every single one.
for panic_countdown in 0..count {
// Refresh the counters.
VERSIONS.store(0, Relaxed);
for i in 0..len {
DROP_COUNTS[i].store(0, Relaxed);
}
let v = $input.to_owned();
let _ = thread::spawn(move || {
let mut v = v;
let mut panic_countdown = panic_countdown;
v.$func(|a, b| {
if panic_countdown == 0 {
SILENCE_PANIC.with(|s| s.set(true));
panic!();
}
panic_countdown -= 1;
a.cmp(b)
})
}).join();
// Check that the number of things dropped is exactly
// what we expect (i.e., the contents of `v`).
for (i, c) in DROP_COUNTS.iter().enumerate().take(len) {
let count = c.load(Relaxed);
assert!(count == 1,
"found drop count == {} for i == {}, len == {}",
count, i, len);
}
// Check that the most recent versions of values were dropped.
assert_eq!(VERSIONS.load(Relaxed), 0);
}
}
}
thread_local!(static SILENCE_PANIC: Cell<bool> = Cell::new(false));
#[test]
#[cfg_attr(target_os = "emscripten", ignore)] // no threads
fn panic_safe() {
let prev = panic::take_hook();
panic::set_hook(Box::new(move |info| {
if !SILENCE_PANIC.with(|s| s.get()) {
prev(info);
}
}));
let mut rng = thread_rng();
for len in (1..20).chain(70..MAX_LEN) {
for &modulus in &[5, 20, 50] {
for &has_runs in &[false, true] {
let mut input = (0..len)
.map(|id| {
DropCounter {
x: rng.next_u32() % modulus,
id: id,
version: Cell::new(0),
}
})
.collect::<Vec<_>>();
if has_runs {
for c in &mut input {
c.x = c.id as u32;
}
for _ in 0..5 {
let a = rng.gen::<usize>() % len;
let b = rng.gen::<usize>() % len;
if a < b {
input[a..b].reverse();
} else {
input.swap(a, b);
}
}
}
test!(input, sort_by);
test!(input, sort_unstable_by);
}
}
}
}
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#[test]
fn repeat_generic_slice() {
assert_eq!([1, 2].repeat(2), vec![1, 2, 1, 2]);
assert_eq!([1, 2, 3, 4].repeat(0), vec![]);
assert_eq!([1, 2, 3, 4].repeat(1), vec![1, 2, 3, 4]);
assert_eq!(
[1, 2, 3, 4].repeat(3),
vec![1, 2, 3, 4, 1, 2, 3, 4, 1, 2, 3, 4]
);
}