rust/library/alloc/tests/slice.rs

2020 lines
57 KiB
Rust
Raw Normal View History

use std::cell::Cell;
use std::cmp::Ordering::{self, Equal, Greater, Less};
use std::convert::identity;
use std::fmt;
use std::mem;
use std::panic;
use std::rc::Rc;
2019-12-22 22:42:04 +00:00
use std::sync::atomic::{AtomicUsize, Ordering::Relaxed};
2019-02-02 09:14:40 +00:00
use rand::distributions::Standard;
2019-12-22 22:42:04 +00:00
use rand::seq::SliceRandom;
use rand::{thread_rng, Rng, RngCore};
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]
2015-07-11 11:34:57 +00:00
fn test_split_first() {
let mut a = vec![11];
let b: &[i32] = &[];
2015-07-11 11:34:57 +00:00
assert!(b.split_first().is_none());
assert_eq!(a.split_first(), Some((&11, b)));
a = vec![11, 12];
let b: &[i32] = &[12];
2015-07-11 11:34:57 +00:00
assert_eq!(a.split_first(), Some((&11, b)));
}
#[test]
2015-07-11 11:34:57 +00:00
fn test_split_first_mut() {
let mut a = vec![11];
let b: &mut [i32] = &mut [];
2015-07-11 11:34:57 +00:00
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];
2015-07-11 11:34:57 +00:00
assert!(a.split_first_mut() == Some((&mut 11, b)));
}
#[test]
2015-07-11 11:34:57 +00:00
fn test_split_last() {
let mut a = vec![11];
let b: &[i32] = &[];
2015-07-11 11:34:57 +00:00
assert!(b.split_last().is_none());
assert_eq!(a.split_last(), Some((&11, b)));
a = vec![11, 12];
let b: &[_] = &[11];
2015-07-11 11:34:57 +00:00
assert_eq!(a.split_last(), Some((&12, b)));
}
#[test]
2015-07-11 11:34:57 +00:00
fn test_split_last_mut() {
let mut a = vec![11];
let b: &mut [i32] = &mut [];
2015-07-11 11:34:57 +00:00
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];
2015-07-11 11:34:57 +00:00
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]
#[cfg_attr(miri, ignore)] // Miri is too slow
fn test_sort() {
let mut rng = thread_rng();
for len in (2..25).chain(500..510) {
2017-06-24 14:51:16 +00:00
for &modulus in &[5, 10, 100, 1000] {
for _ in 0..10 {
2019-12-22 22:42:04 +00:00
let orig: Vec<_> =
rng.sample_iter::<i32, _>(&Standard).map(|x| x % modulus).take(len).collect();
2017-06-24 14:51:16 +00:00
// 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]));
2018-03-01 13:39:52 +00:00
// Sort in lexicographic order.
2018-03-16 14:37:17 +00:00
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);
2018-03-01 13:39:52 +00:00
2017-06-24 14:51:16 +00:00
// 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;
}
std: Depend directly on crates.io crates Ever since we added a Cargo-based build system for the compiler the standard library has always been a little special, it's never been able to depend on crates.io crates for runtime dependencies. This has been a result of various limitations, namely that Cargo doesn't understand that crates from crates.io depend on libcore, so Cargo tries to build crates before libcore is finished. I had an idea this afternoon, however, which lifts the strategy from #52919 to directly depend on crates.io crates from the standard library. After all is said and done this removes a whopping three submodules that we need to manage! The basic idea here is that for any crate `std` depends on it adds an *optional* dependency on an empty crate on crates.io, in this case named `rustc-std-workspace-core`. This crate is overridden via `[patch]` in this repository to point to a local crate we write, and *that* has a `path` dependency on libcore. Note that all `no_std` crates also depend on `compiler_builtins`, but if we're not using submodules we can publish `compiler_builtins` to crates.io and all crates can depend on it anyway! The basic strategy then looks like: * The standard library (or some transitive dep) decides to depend on a crate `foo`. * The standard library adds ```toml [dependencies] foo = { version = "0.1", features = ['rustc-dep-of-std'] } ``` * The crate `foo` has an optional dependency on `rustc-std-workspace-core` * The crate `foo` has an optional dependency on `compiler_builtins` * The crate `foo` has a feature `rustc-dep-of-std` which activates these crates and any other necessary infrastructure in the crate. A sample commit for `dlmalloc` [turns out to be quite simple][commit]. After that all `no_std` crates should largely build "as is" and still be publishable on crates.io! Notably they should be able to continue to use stable Rust if necessary, since the `rename-dependency` feature of Cargo is soon stabilizing. As a proof of concept, this commit removes the `dlmalloc`, `libcompiler_builtins`, and `libc` submodules from this repository. Long thorns in our side these are now gone for good and we can directly depend on crates.io! It's hoped that in the long term we can bring in other crates as necessary, but for now this is largely intended to simply make it easier to manage these crates and remove submodules. This should be a transparent non-breaking change for all users, but one possible stickler is that this almost for sure breaks out-of-tree `std`-building tools like `xargo` and `cargo-xbuild`. I think it should be relatively easy to get them working, however, as all that's needed is an entry in the `[patch]` section used to build the standard library. Hopefully we can work with these tools to solve this problem! [commit]: https://github.com/alexcrichton/dlmalloc-rs/commit/28ee12db813a3b650a7c25d1c36d2c17dcb88ae3
2018-11-20 05:52:50 +00:00
v.sort_by(|_, _| *[Less, Equal, Greater].choose(&mut rng).unwrap());
v.sort();
for i in 0..v.len() {
assert_eq!(v[i], i as i32);
}
2017-03-17 14:05:44 +00:00
// Should not panic.
[0i32; 0].sort();
[(); 10].sort();
[(); 100].sort();
let mut v = [0xDEADBEEFu64];
v.sort();
assert!(v == [0xDEADBEEF]);
}
#[test]
fn test_sort_stability() {
// Miri is too slow
let large_range = if cfg!(miri) { 0..0 } else { 500..510 };
let rounds = if cfg!(miri) { 1 } else { 10 };
2019-04-17 07:47:36 +00:00
for len in (2..25).chain(large_range) {
for _ in 0..rounds {
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.
2019-02-02 09:14:40 +00:00
let orig: Vec<_> = (0..len)
2016-10-16 10:18:22 +00:00
.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
2017-12-16 20:29:09 +00:00
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
2017-12-16 20:29:09 +00:00
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
2017-12-16 20:29:09 +00:00
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
2017-12-16 20:29:09 +00:00
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 20:29:09 +00:00
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 20:29:09 +00:00
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 20:29:09 +00:00
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();
2019-12-22 22:42:04 +00:00
v.rotate_left(1000 - 389);
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 20:29:09 +00:00
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);
2019-12-22 22:42:04 +00:00
};
}
#[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];
2019-12-22 22:42:04 +00:00
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];
2019-12-22 22:42:04 +00:00
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_splitator_inclusive() {
let xs = &[1, 2, 3, 4, 5];
let splits: &[&[_]] = &[&[1, 2], &[3, 4], &[5]];
assert_eq!(xs.split_inclusive(|x| *x % 2 == 0).collect::<Vec<_>>(), splits);
let splits: &[&[_]] = &[&[1], &[2, 3, 4, 5]];
assert_eq!(xs.split_inclusive(|x| *x == 1).collect::<Vec<_>>(), splits);
let splits: &[&[_]] = &[&[1, 2, 3, 4, 5]];
assert_eq!(xs.split_inclusive(|x| *x == 5).collect::<Vec<_>>(), splits);
let splits: &[&[_]] = &[&[1, 2, 3, 4, 5]];
assert_eq!(xs.split_inclusive(|x| *x == 10).collect::<Vec<_>>(), splits);
let splits: &[&[_]] = &[&[1], &[2], &[3], &[4], &[5]];
assert_eq!(xs.split_inclusive(|_| true).collect::<Vec<&[i32]>>(), splits);
let xs: &[i32] = &[];
let splits: &[&[i32]] = &[&[]];
assert_eq!(xs.split_inclusive(|x| *x == 5).collect::<Vec<&[i32]>>(), splits);
}
#[test]
fn test_splitator_inclusive_reverse() {
let xs = &[1, 2, 3, 4, 5];
let splits: &[&[_]] = &[&[5], &[3, 4], &[1, 2]];
assert_eq!(xs.split_inclusive(|x| *x % 2 == 0).rev().collect::<Vec<_>>(), splits);
let splits: &[&[_]] = &[&[2, 3, 4, 5], &[1]];
assert_eq!(xs.split_inclusive(|x| *x == 1).rev().collect::<Vec<_>>(), splits);
let splits: &[&[_]] = &[&[1, 2, 3, 4, 5]];
assert_eq!(xs.split_inclusive(|x| *x == 5).rev().collect::<Vec<_>>(), splits);
let splits: &[&[_]] = &[&[1, 2, 3, 4, 5]];
assert_eq!(xs.split_inclusive(|x| *x == 10).rev().collect::<Vec<_>>(), splits);
let splits: &[&[_]] = &[&[5], &[4], &[3], &[2], &[1]];
assert_eq!(xs.split_inclusive(|_| true).rev().collect::<Vec<_>>(), splits);
let xs: &[i32] = &[];
let splits: &[&[i32]] = &[&[]];
assert_eq!(xs.split_inclusive(|x| *x == 5).rev().collect::<Vec<_>>(), splits);
}
#[test]
fn test_splitator_mut_inclusive() {
let xs = &mut [1, 2, 3, 4, 5];
let splits: &[&[_]] = &[&[1, 2], &[3, 4], &[5]];
assert_eq!(xs.split_inclusive_mut(|x| *x % 2 == 0).collect::<Vec<_>>(), splits);
let splits: &[&[_]] = &[&[1], &[2, 3, 4, 5]];
assert_eq!(xs.split_inclusive_mut(|x| *x == 1).collect::<Vec<_>>(), splits);
let splits: &[&[_]] = &[&[1, 2, 3, 4, 5]];
assert_eq!(xs.split_inclusive_mut(|x| *x == 5).collect::<Vec<_>>(), splits);
let splits: &[&[_]] = &[&[1, 2, 3, 4, 5]];
assert_eq!(xs.split_inclusive_mut(|x| *x == 10).collect::<Vec<_>>(), splits);
let splits: &[&[_]] = &[&[1], &[2], &[3], &[4], &[5]];
assert_eq!(xs.split_inclusive_mut(|_| true).collect::<Vec<_>>(), splits);
let xs: &mut [i32] = &mut [];
let splits: &[&[i32]] = &[&[]];
assert_eq!(xs.split_inclusive_mut(|x| *x == 5).collect::<Vec<_>>(), splits);
}
#[test]
fn test_splitator_mut_inclusive_reverse() {
let xs = &mut [1, 2, 3, 4, 5];
let splits: &[&[_]] = &[&[5], &[3, 4], &[1, 2]];
assert_eq!(xs.split_inclusive_mut(|x| *x % 2 == 0).rev().collect::<Vec<_>>(), splits);
let splits: &[&[_]] = &[&[2, 3, 4, 5], &[1]];
assert_eq!(xs.split_inclusive_mut(|x| *x == 1).rev().collect::<Vec<_>>(), splits);
let splits: &[&[_]] = &[&[1, 2, 3, 4, 5]];
assert_eq!(xs.split_inclusive_mut(|x| *x == 5).rev().collect::<Vec<_>>(), splits);
let splits: &[&[_]] = &[&[1, 2, 3, 4, 5]];
assert_eq!(xs.split_inclusive_mut(|x| *x == 10).rev().collect::<Vec<_>>(), splits);
let splits: &[&[_]] = &[&[5], &[4], &[3], &[2], &[1]];
assert_eq!(xs.split_inclusive_mut(|_| true).rev().collect::<Vec<_>>(), splits);
let xs: &mut [i32] = &mut [];
let splits: &[&[i32]] = &[&[]];
assert_eq!(xs.split_inclusive_mut(|x| *x == 5).rev().collect::<Vec<_>>(), 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]];
2019-12-22 22:42:04 +00:00
assert_eq!(xs.splitn_mut(1, |x| *x % 2 == 0).collect::<Vec<_>>(), splits);
let splits: &[&mut [_]] = &[&mut [1], &mut [3, 4, 5]];
2019-12-22 22:42:04 +00:00
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_split_iterators_size_hint() {
#[derive(Copy, Clone)]
enum Bounds {
Lower,
Upper,
}
fn assert_precise_size_hints(mut it: impl Iterator, which: Bounds, context: impl fmt::Display) {
match which {
Bounds::Lower => {
let mut lower_bounds = vec![it.size_hint().0];
while let Some(_) = it.next() {
lower_bounds.push(it.size_hint().0);
}
let target: Vec<_> = (0..lower_bounds.len()).rev().collect();
assert_eq!(lower_bounds, target, "incorrect lower bounds: {}", context);
}
Bounds::Upper => {
let mut upper_bounds = vec![it.size_hint().1];
while let Some(_) = it.next() {
upper_bounds.push(it.size_hint().1);
}
let target: Vec<_> = (0..upper_bounds.len()).map(Some).rev().collect();
assert_eq!(upper_bounds, target, "incorrect upper bounds: {}", context);
}
}
}
for len in 0..=2 {
let mut v: Vec<u8> = (0..len).collect();
// p: predicate, b: bound selection
for (p, b) in [
// with a predicate always returning false, the split*-iterators
// become maximally short, so the size_hint lower bounds are correct
((|_| false) as fn(&_) -> _, Bounds::Lower),
// with a predicate always returning true, the split*-iterators
// become maximally long, so the size_hint upper bounds are correct
((|_| true) as fn(&_) -> _, Bounds::Upper),
] {
use assert_precise_size_hints as a;
use format_args as f;
a(v.split(p), b, "split");
a(v.split_mut(p), b, "split_mut");
a(v.split_inclusive(p), b, "split_inclusive");
a(v.split_inclusive_mut(p), b, "split_inclusive_mut");
a(v.rsplit(p), b, "rsplit");
a(v.rsplit_mut(p), b, "rsplit_mut");
for n in 0..=3 {
a(v.splitn(n, p), b, f!("splitn, n = {}", n));
a(v.splitn_mut(n, p), b, f!("splitn_mut, n = {}", n));
a(v.rsplitn(n, p), b, f!("rsplitn, n = {}", n));
a(v.rsplitn_mut(n, p), b, f!("rsplitn_mut, n = {}", n));
}
}
}
}
#[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 {
2019-12-22 22:42:04 +00:00
($x:expr, $x_str:expr) => {{
let (x, x_str) = ($x, $x_str);
assert_eq!(format!("{:?}", x), x_str);
assert_eq!(format!("{:?}", x), x_str);
2019-12-22 22:42:04 +00:00
}};
}
let empty = Vec::<i32>::new();
test_show_vec!(empty, "[]");
test_show_vec!(vec![1], "[1]");
test_show_vec!(vec![1, 2, 3], "[1, 2, 3]");
test_show_vec!(vec![vec![], vec![1], vec![1, 1]], "[[], [1], [1, 1]]");
let empty_mut: &mut [i32] = &mut [];
test_show_vec!(empty_mut, "[]");
let v = &mut [1];
test_show_vec!(v, "[1]");
let v = &mut [1, 2, 3];
test_show_vec!(v, "[1, 2, 3]");
let v: &mut [&mut [_]] = &mut [&mut [], &mut [1], &mut [1, 1]];
test_show_vec!(v, "[[], [1], [1, 1]]");
}
#[test]
fn test_vec_default() {
macro_rules! t {
($ty:ty) => {{
let v: $ty = Default::default();
assert!(v.is_empty());
2019-12-22 22:42:04 +00:00
}};
}
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_in_place_iterator_specialization() {
let src: Box<[usize]> = box [1, 2, 3];
let src_ptr = src.as_ptr();
let sink: Box<_> = src.into_vec().into_iter().map(std::convert::identity).collect();
let sink_ptr = sink.as_ptr();
assert_eq!(src_ptr, sink_ptr);
}
#[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::atomic::{AtomicUsize, Ordering};
2019-12-22 22:42:04 +00:00
use std::sync::Arc;
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!()
}
2019-12-22 22:42:04 +00:00
Canary { count: self.count.clone(), panics: self.panics }
}
}
let drop_count = Arc::new(AtomicUsize::new(0));
2019-12-22 22:42:04 +00:00
let canary = Canary { count: drop_count.clone(), panics: false };
let panic = Canary { count: drop_count.clone(), panics: true };
std::panic::catch_unwind(move || {
2019-12-22 22:42:04 +00:00
// When xs is dropped, +5.
let xs =
vec![canary.clone(), canary.clone(), canary.clone(), panic, canary].into_boxed_slice();
2019-12-22 22:42:04 +00:00
// When panic is cloned, +3.
xs.clone();
})
.unwrap_err();
// Total = 8
assert_eq!(drop_count.load(Ordering::SeqCst), 8);
}
2016-02-23 07:06:53 +00:00
#[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 = "source slice length (4) does not match destination slice length (5)")]
2016-02-23 07:06:53 +00:00
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 = "source slice length (4) does not match destination slice length (3)")]
2016-02-23 07:06:53 +00:00
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.
2019-12-22 22:42:04 +00:00
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),
];
2019-01-26 16:14:49 +00:00
static VERSIONS: AtomicUsize = AtomicUsize::new(0);
#[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;
2019-12-22 22:42:04 +00:00
$input.to_owned().$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 = $input.to_owned();
let _ = std::panic::catch_unwind(move || {
let mut v = v;
let mut panic_countdown = panic_countdown;
v.$func(|a, b| {
if panic_countdown == 0 {
SILENCE_PANIC.with(|s| s.set(true));
panic!();
}
panic_countdown -= 1;
a.cmp(b)
})
});
// 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);
2019-12-22 22:42:04 +00:00
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);
}
2019-12-22 22:42:04 +00:00
};
}
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();
2020-07-31 12:03:42 +00:00
// Miri is too slow (but still need to `chain` to make the types match)
let lens = if cfg!(miri) { (1..10).chain(0..0) } else { (1..20).chain(70..MAX_LEN) };
let moduli: &[u32] = if cfg!(miri) { &[5] } else { &[5, 20, 50] };
2019-11-22 22:35:56 +00:00
for len in lens {
for &modulus in moduli {
for &has_runs in &[false, true] {
let mut input = (0..len)
2019-12-22 22:42:04 +00:00
.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);
}
}
}
// Set default panic hook again.
drop(panic::take_hook());
}
2018-04-28 16:19:06 +00:00
#[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]);
2019-12-22 22:42:04 +00:00
assert_eq!([1, 2, 3, 4].repeat(3), vec![1, 2, 3, 4, 1, 2, 3, 4, 1, 2, 3, 4]);
2018-04-28 16:19:06 +00:00
}
#[test]
#[allow(unreachable_patterns)]
fn subslice_patterns() {
// This test comprehensively checks the passing static and dynamic semantics
// of subslice patterns `..`, `x @ ..`, `ref x @ ..`, and `ref mut @ ..`
// in slice patterns `[$($pat), $(,)?]` .
#[derive(PartialEq, Debug, Clone)]
struct N(u8);
macro_rules! n {
($($e:expr),* $(,)?) => {
[$(N($e)),*]
}
}
macro_rules! c {
($inp:expr, $typ:ty, $out:expr $(,)?) => {
assert_eq!($out, identity::<$typ>($inp))
};
}
macro_rules! m {
($e:expr, $p:pat => $b:expr) => {
match $e {
$p => $b,
_ => panic!(),
}
};
}
// == Slices ==
// Matching slices using `ref` patterns:
let mut v = vec![N(0), N(1), N(2), N(3), N(4)];
let mut vc = (0..=4).collect::<Vec<u8>>();
let [..] = v[..]; // Always matches.
m!(v[..], [N(0), ref sub @ .., N(4)] => c!(sub, &[N], n![1, 2, 3]));
m!(v[..], [N(0), ref sub @ ..] => c!(sub, &[N], n![1, 2, 3, 4]));
m!(v[..], [ref sub @ .., N(4)] => c!(sub, &[N], n![0, 1, 2, 3]));
m!(v[..], [ref sub @ .., _, _, _, _, _] => c!(sub, &[N], &n![] as &[N]));
m!(v[..], [_, _, _, _, _, ref sub @ ..] => c!(sub, &[N], &n![] as &[N]));
m!(vc[..], [x, .., y] => c!((x, y), (u8, u8), (0, 4)));
// Matching slices using `ref mut` patterns:
let [..] = v[..]; // Always matches.
m!(v[..], [N(0), ref mut sub @ .., N(4)] => c!(sub, &mut [N], n![1, 2, 3]));
m!(v[..], [N(0), ref mut sub @ ..] => c!(sub, &mut [N], n![1, 2, 3, 4]));
m!(v[..], [ref mut sub @ .., N(4)] => c!(sub, &mut [N], n![0, 1, 2, 3]));
m!(v[..], [ref mut sub @ .., _, _, _, _, _] => c!(sub, &mut [N], &mut n![] as &mut [N]));
m!(v[..], [_, _, _, _, _, ref mut sub @ ..] => c!(sub, &mut [N], &mut n![] as &mut [N]));
m!(vc[..], [x, .., y] => c!((x, y), (u8, u8), (0, 4)));
// Matching slices using default binding modes (&):
let [..] = &v[..]; // Always matches.
m!(&v[..], [N(0), sub @ .., N(4)] => c!(sub, &[N], n![1, 2, 3]));
m!(&v[..], [N(0), sub @ ..] => c!(sub, &[N], n![1, 2, 3, 4]));
m!(&v[..], [sub @ .., N(4)] => c!(sub, &[N], n![0, 1, 2, 3]));
m!(&v[..], [sub @ .., _, _, _, _, _] => c!(sub, &[N], &n![] as &[N]));
m!(&v[..], [_, _, _, _, _, sub @ ..] => c!(sub, &[N], &n![] as &[N]));
m!(&vc[..], [x, .., y] => c!((x, y), (&u8, &u8), (&0, &4)));
// Matching slices using default binding modes (&mut):
let [..] = &mut v[..]; // Always matches.
m!(&mut v[..], [N(0), sub @ .., N(4)] => c!(sub, &mut [N], n![1, 2, 3]));
m!(&mut v[..], [N(0), sub @ ..] => c!(sub, &mut [N], n![1, 2, 3, 4]));
m!(&mut v[..], [sub @ .., N(4)] => c!(sub, &mut [N], n![0, 1, 2, 3]));
m!(&mut v[..], [sub @ .., _, _, _, _, _] => c!(sub, &mut [N], &mut n![] as &mut [N]));
m!(&mut v[..], [_, _, _, _, _, sub @ ..] => c!(sub, &mut [N], &mut n![] as &mut [N]));
m!(&mut vc[..], [x, .., y] => c!((x, y), (&mut u8, &mut u8), (&mut 0, &mut 4)));
// == Arrays ==
let mut v = n![0, 1, 2, 3, 4];
let vc = [0, 1, 2, 3, 4];
// Matching arrays by value:
m!(v.clone(), [N(0), sub @ .., N(4)] => c!(sub, [N; 3], n![1, 2, 3]));
m!(v.clone(), [N(0), sub @ ..] => c!(sub, [N; 4], n![1, 2, 3, 4]));
m!(v.clone(), [sub @ .., N(4)] => c!(sub, [N; 4], n![0, 1, 2, 3]));
m!(v.clone(), [sub @ .., _, _, _, _, _] => c!(sub, [N; 0], n![] as [N; 0]));
m!(v.clone(), [_, _, _, _, _, sub @ ..] => c!(sub, [N; 0], n![] as [N; 0]));
m!(v.clone(), [x, .., y] => c!((x, y), (N, N), (N(0), N(4))));
m!(v.clone(), [..] => ());
// Matching arrays by ref patterns:
m!(v, [N(0), ref sub @ .., N(4)] => c!(sub, &[N; 3], &n![1, 2, 3]));
m!(v, [N(0), ref sub @ ..] => c!(sub, &[N; 4], &n![1, 2, 3, 4]));
m!(v, [ref sub @ .., N(4)] => c!(sub, &[N; 4], &n![0, 1, 2, 3]));
m!(v, [ref sub @ .., _, _, _, _, _] => c!(sub, &[N; 0], &n![] as &[N; 0]));
m!(v, [_, _, _, _, _, ref sub @ ..] => c!(sub, &[N; 0], &n![] as &[N; 0]));
m!(vc, [x, .., y] => c!((x, y), (u8, u8), (0, 4)));
// Matching arrays by ref mut patterns:
m!(v, [N(0), ref mut sub @ .., N(4)] => c!(sub, &mut [N; 3], &mut n![1, 2, 3]));
m!(v, [N(0), ref mut sub @ ..] => c!(sub, &mut [N; 4], &mut n![1, 2, 3, 4]));
m!(v, [ref mut sub @ .., N(4)] => c!(sub, &mut [N; 4], &mut n![0, 1, 2, 3]));
m!(v, [ref mut sub @ .., _, _, _, _, _] => c!(sub, &mut [N; 0], &mut n![] as &mut [N; 0]));
m!(v, [_, _, _, _, _, ref mut sub @ ..] => c!(sub, &mut [N; 0], &mut n![] as &mut [N; 0]));
// Matching arrays by default binding modes (&):
m!(&v, [N(0), sub @ .., N(4)] => c!(sub, &[N; 3], &n![1, 2, 3]));
m!(&v, [N(0), sub @ ..] => c!(sub, &[N; 4], &n![1, 2, 3, 4]));
m!(&v, [sub @ .., N(4)] => c!(sub, &[N; 4], &n![0, 1, 2, 3]));
m!(&v, [sub @ .., _, _, _, _, _] => c!(sub, &[N; 0], &n![] as &[N; 0]));
m!(&v, [_, _, _, _, _, sub @ ..] => c!(sub, &[N; 0], &n![] as &[N; 0]));
m!(&v, [..] => ());
m!(&v, [x, .., y] => c!((x, y), (&N, &N), (&N(0), &N(4))));
// Matching arrays by default binding modes (&mut):
m!(&mut v, [N(0), sub @ .., N(4)] => c!(sub, &mut [N; 3], &mut n![1, 2, 3]));
m!(&mut v, [N(0), sub @ ..] => c!(sub, &mut [N; 4], &mut n![1, 2, 3, 4]));
m!(&mut v, [sub @ .., N(4)] => c!(sub, &mut [N; 4], &mut n![0, 1, 2, 3]));
m!(&mut v, [sub @ .., _, _, _, _, _] => c!(sub, &mut [N; 0], &mut n![] as &[N; 0]));
m!(&mut v, [_, _, _, _, _, sub @ ..] => c!(sub, &mut [N; 0], &mut n![] as &[N; 0]));
m!(&mut v, [..] => ());
m!(&mut v, [x, .., y] => c!((x, y), (&mut N, &mut N), (&mut N(0), &mut N(4))));
}
#[test]
fn test_group_by() {
2020-12-10 12:42:31 +00:00
let slice = &[1, 1, 1, 3, 3, 2, 2, 2, 1, 0];
let mut iter = slice.group_by(|a, b| a == b);
assert_eq!(iter.next(), Some(&[1, 1, 1][..]));
assert_eq!(iter.next(), Some(&[3, 3][..]));
assert_eq!(iter.next(), Some(&[2, 2, 2][..]));
2020-12-10 12:42:31 +00:00
assert_eq!(iter.next(), Some(&[1][..]));
assert_eq!(iter.next(), Some(&[0][..]));
assert_eq!(iter.next(), None);
let mut iter = slice.group_by(|a, b| a == b);
2020-12-10 12:42:31 +00:00
assert_eq!(iter.next_back(), Some(&[0][..]));
assert_eq!(iter.next_back(), Some(&[1][..]));
assert_eq!(iter.next_back(), Some(&[2, 2, 2][..]));
assert_eq!(iter.next_back(), Some(&[3, 3][..]));
assert_eq!(iter.next_back(), Some(&[1, 1, 1][..]));
assert_eq!(iter.next_back(), None);
2020-12-10 10:17:41 +00:00
let mut iter = slice.group_by(|a, b| a == b);
assert_eq!(iter.next(), Some(&[1, 1, 1][..]));
2020-12-10 12:42:31 +00:00
assert_eq!(iter.next_back(), Some(&[0][..]));
2020-12-10 10:17:41 +00:00
assert_eq!(iter.next(), Some(&[3, 3][..]));
2020-12-10 12:42:31 +00:00
assert_eq!(iter.next_back(), Some(&[1][..]));
assert_eq!(iter.next(), Some(&[2, 2, 2][..]));
2020-12-10 10:17:41 +00:00
assert_eq!(iter.next_back(), None);
}
#[test]
fn test_group_by_mut() {
2020-12-10 12:42:31 +00:00
let slice = &mut [1, 1, 1, 3, 3, 2, 2, 2, 1, 0];
2020-12-10 10:17:41 +00:00
let mut iter = slice.group_by_mut(|a, b| a == b);
assert_eq!(iter.next(), Some(&mut [1, 1, 1][..]));
assert_eq!(iter.next(), Some(&mut [3, 3][..]));
assert_eq!(iter.next(), Some(&mut [2, 2, 2][..]));
2020-12-10 12:42:31 +00:00
assert_eq!(iter.next(), Some(&mut [1][..]));
assert_eq!(iter.next(), Some(&mut [0][..]));
2020-12-10 10:17:41 +00:00
assert_eq!(iter.next(), None);
let mut iter = slice.group_by_mut(|a, b| a == b);
2020-12-10 12:42:31 +00:00
assert_eq!(iter.next_back(), Some(&mut [0][..]));
assert_eq!(iter.next_back(), Some(&mut [1][..]));
2020-12-10 10:17:41 +00:00
assert_eq!(iter.next_back(), Some(&mut [2, 2, 2][..]));
assert_eq!(iter.next_back(), Some(&mut [3, 3][..]));
assert_eq!(iter.next_back(), Some(&mut [1, 1, 1][..]));
assert_eq!(iter.next_back(), None);
let mut iter = slice.group_by_mut(|a, b| a == b);
assert_eq!(iter.next(), Some(&mut [1, 1, 1][..]));
2020-12-10 12:42:31 +00:00
assert_eq!(iter.next_back(), Some(&mut [0][..]));
2020-12-10 10:17:41 +00:00
assert_eq!(iter.next(), Some(&mut [3, 3][..]));
2020-12-10 12:42:31 +00:00
assert_eq!(iter.next_back(), Some(&mut [1][..]));
assert_eq!(iter.next(), Some(&mut [2, 2, 2][..]));
2020-12-10 10:17:41 +00:00
assert_eq!(iter.next_back(), None);
}