rust/library/alloc/tests/vec.rs
Waffle d5c221107e add Vec::extend_from_within method
Implement <https://github.com/rust-lang/rfcs/pull/2714>, changes from the RFC:
- Rename the method `append_from_within` => `extend_from_within`
- Loose :Copy bound => :Clone
- Specialize in case of :Copy

This commit also adds `Vec::split_at_spare` private method and use it to implement
`Vec::spare_capacity_mut` and `Vec::extend_from_within`. This method returns 2
slices - initialized elements (same as `&mut vec[..]`) and uninitialized but
allocated space (same as `vec.spare_capacity_mut()`).
2021-01-31 22:30:19 +03:00

2027 lines
53 KiB
Rust

use std::borrow::Cow;
use std::cell::Cell;
use std::collections::TryReserveError::*;
use std::fmt::Debug;
use std::iter::InPlaceIterable;
use std::mem::{size_of, swap};
use std::ops::Bound::*;
use std::panic::{catch_unwind, AssertUnwindSafe};
use std::rc::Rc;
use std::vec::{Drain, IntoIter};
struct DropCounter<'a> {
count: &'a mut u32,
}
impl Drop for DropCounter<'_> {
fn drop(&mut self) {
*self.count += 1;
}
}
#[test]
fn test_small_vec_struct() {
assert_eq!(size_of::<Vec<u8>>(), size_of::<usize>() * 3);
}
#[test]
fn test_double_drop() {
struct TwoVec<T> {
x: Vec<T>,
y: Vec<T>,
}
let (mut count_x, mut count_y) = (0, 0);
{
let mut tv = TwoVec { x: Vec::new(), y: Vec::new() };
tv.x.push(DropCounter { count: &mut count_x });
tv.y.push(DropCounter { count: &mut count_y });
// If Vec had a drop flag, here is where it would be zeroed.
// Instead, it should rely on its internal state to prevent
// doing anything significant when dropped multiple times.
drop(tv.x);
// Here tv goes out of scope, tv.y should be dropped, but not tv.x.
}
assert_eq!(count_x, 1);
assert_eq!(count_y, 1);
}
#[test]
fn test_reserve() {
let mut v = Vec::new();
assert_eq!(v.capacity(), 0);
v.reserve(2);
assert!(v.capacity() >= 2);
for i in 0..16 {
v.push(i);
}
assert!(v.capacity() >= 16);
v.reserve(16);
assert!(v.capacity() >= 32);
v.push(16);
v.reserve(16);
assert!(v.capacity() >= 33)
}
#[test]
fn test_zst_capacity() {
assert_eq!(Vec::<()>::new().capacity(), usize::MAX);
}
#[test]
fn test_indexing() {
let v: Vec<isize> = vec![10, 20];
assert_eq!(v[0], 10);
assert_eq!(v[1], 20);
let mut x: usize = 0;
assert_eq!(v[x], 10);
assert_eq!(v[x + 1], 20);
x = x + 1;
assert_eq!(v[x], 20);
assert_eq!(v[x - 1], 10);
}
#[test]
fn test_debug_fmt() {
let vec1: Vec<isize> = vec![];
assert_eq!("[]", format!("{:?}", vec1));
let vec2 = vec![0, 1];
assert_eq!("[0, 1]", format!("{:?}", vec2));
let slice: &[isize] = &[4, 5];
assert_eq!("[4, 5]", format!("{:?}", slice));
}
#[test]
fn test_push() {
let mut v = vec![];
v.push(1);
assert_eq!(v, [1]);
v.push(2);
assert_eq!(v, [1, 2]);
v.push(3);
assert_eq!(v, [1, 2, 3]);
}
#[test]
fn test_extend() {
let mut v = Vec::new();
let mut w = Vec::new();
v.extend(w.clone());
assert_eq!(v, &[]);
v.extend(0..3);
for i in 0..3 {
w.push(i)
}
assert_eq!(v, w);
v.extend(3..10);
for i in 3..10 {
w.push(i)
}
assert_eq!(v, w);
v.extend(w.clone()); // specializes to `append`
assert!(v.iter().eq(w.iter().chain(w.iter())));
// Zero sized types
#[derive(PartialEq, Debug)]
struct Foo;
let mut a = Vec::new();
let b = vec![Foo, Foo];
a.extend(b);
assert_eq!(a, &[Foo, Foo]);
// Double drop
let mut count_x = 0;
{
let mut x = Vec::new();
let y = vec![DropCounter { count: &mut count_x }];
x.extend(y);
}
assert_eq!(count_x, 1);
}
#[test]
fn test_extend_from_slice() {
let a: Vec<isize> = vec![1, 2, 3, 4, 5];
let b: Vec<isize> = vec![6, 7, 8, 9, 0];
let mut v: Vec<isize> = a;
v.extend_from_slice(&b);
assert_eq!(v, [1, 2, 3, 4, 5, 6, 7, 8, 9, 0]);
}
#[test]
fn test_extend_ref() {
let mut v = vec![1, 2];
v.extend(&[3, 4, 5]);
assert_eq!(v.len(), 5);
assert_eq!(v, [1, 2, 3, 4, 5]);
let w = vec![6, 7];
v.extend(&w);
assert_eq!(v.len(), 7);
assert_eq!(v, [1, 2, 3, 4, 5, 6, 7]);
}
#[test]
fn test_slice_from_ref() {
let values = vec![1, 2, 3, 4, 5];
let slice = &values[1..3];
assert_eq!(slice, [2, 3]);
}
#[test]
fn test_slice_from_mut() {
let mut values = vec![1, 2, 3, 4, 5];
{
let slice = &mut values[2..];
assert!(slice == [3, 4, 5]);
for p in slice {
*p += 2;
}
}
assert!(values == [1, 2, 5, 6, 7]);
}
#[test]
fn test_slice_to_mut() {
let mut values = vec![1, 2, 3, 4, 5];
{
let slice = &mut values[..2];
assert!(slice == [1, 2]);
for p in slice {
*p += 1;
}
}
assert!(values == [2, 3, 3, 4, 5]);
}
#[test]
fn test_split_at_mut() {
let mut values = vec![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_eq!(values, [2, 3, 5, 6, 7]);
}
#[test]
fn test_clone() {
let v: Vec<i32> = vec![];
let w = vec![1, 2, 3];
assert_eq!(v, v.clone());
let z = w.clone();
assert_eq!(w, z);
// they should be disjoint in memory.
assert!(w.as_ptr() != z.as_ptr())
}
#[test]
fn test_clone_from() {
let mut v = vec![];
let three: Vec<Box<_>> = vec![box 1, box 2, box 3];
let two: Vec<Box<_>> = vec![box 4, box 5];
// zero, long
v.clone_from(&three);
assert_eq!(v, three);
// equal
v.clone_from(&three);
assert_eq!(v, three);
// long, short
v.clone_from(&two);
assert_eq!(v, two);
// short, long
v.clone_from(&three);
assert_eq!(v, three)
}
#[test]
fn test_retain() {
let mut vec = vec![1, 2, 3, 4];
vec.retain(|&x| x % 2 == 0);
assert_eq!(vec, [2, 4]);
}
#[test]
fn test_dedup() {
fn case(a: Vec<i32>, b: Vec<i32>) {
let mut v = a;
v.dedup();
assert_eq!(v, b);
}
case(vec![], vec![]);
case(vec![1], vec![1]);
case(vec![1, 1], vec![1]);
case(vec![1, 2, 3], vec![1, 2, 3]);
case(vec![1, 1, 2, 3], vec![1, 2, 3]);
case(vec![1, 2, 2, 3], vec![1, 2, 3]);
case(vec![1, 2, 3, 3], vec![1, 2, 3]);
case(vec![1, 1, 2, 2, 2, 3, 3], vec![1, 2, 3]);
}
#[test]
fn test_dedup_by_key() {
fn case(a: Vec<i32>, b: Vec<i32>) {
let mut v = a;
v.dedup_by_key(|i| *i / 10);
assert_eq!(v, b);
}
case(vec![], vec![]);
case(vec![10], vec![10]);
case(vec![10, 11], vec![10]);
case(vec![10, 20, 30], vec![10, 20, 30]);
case(vec![10, 11, 20, 30], vec![10, 20, 30]);
case(vec![10, 20, 21, 30], vec![10, 20, 30]);
case(vec![10, 20, 30, 31], vec![10, 20, 30]);
case(vec![10, 11, 20, 21, 22, 30, 31], vec![10, 20, 30]);
}
#[test]
fn test_dedup_by() {
let mut vec = vec!["foo", "bar", "Bar", "baz", "bar"];
vec.dedup_by(|a, b| a.eq_ignore_ascii_case(b));
assert_eq!(vec, ["foo", "bar", "baz", "bar"]);
let mut vec = vec![("foo", 1), ("foo", 2), ("bar", 3), ("bar", 4), ("bar", 5)];
vec.dedup_by(|a, b| {
a.0 == b.0 && {
b.1 += a.1;
true
}
});
assert_eq!(vec, [("foo", 3), ("bar", 12)]);
}
#[test]
fn test_dedup_unique() {
let mut v0: Vec<Box<_>> = vec![box 1, box 1, box 2, box 3];
v0.dedup();
let mut v1: Vec<Box<_>> = vec![box 1, box 2, box 2, box 3];
v1.dedup();
let mut v2: Vec<Box<_>> = vec![box 1, box 2, box 3, box 3];
v2.dedup();
// If the boxed pointers were leaked or otherwise misused, valgrind
// and/or rt should raise errors.
}
#[test]
fn zero_sized_values() {
let mut v = Vec::new();
assert_eq!(v.len(), 0);
v.push(());
assert_eq!(v.len(), 1);
v.push(());
assert_eq!(v.len(), 2);
assert_eq!(v.pop(), Some(()));
assert_eq!(v.pop(), Some(()));
assert_eq!(v.pop(), None);
assert_eq!(v.iter().count(), 0);
v.push(());
assert_eq!(v.iter().count(), 1);
v.push(());
assert_eq!(v.iter().count(), 2);
for &() in &v {}
assert_eq!(v.iter_mut().count(), 2);
v.push(());
assert_eq!(v.iter_mut().count(), 3);
v.push(());
assert_eq!(v.iter_mut().count(), 4);
for &mut () in &mut v {}
unsafe {
v.set_len(0);
}
assert_eq!(v.iter_mut().count(), 0);
}
#[test]
fn test_partition() {
assert_eq!(vec![].into_iter().partition(|x: &i32| *x < 3), (vec![], vec![]));
assert_eq!(vec![1, 2, 3].into_iter().partition(|x| *x < 4), (vec![1, 2, 3], vec![]));
assert_eq!(vec![1, 2, 3].into_iter().partition(|x| *x < 2), (vec![1], vec![2, 3]));
assert_eq!(vec![1, 2, 3].into_iter().partition(|x| *x < 0), (vec![], vec![1, 2, 3]));
}
#[test]
fn test_zip_unzip() {
let z1 = vec![(1, 4), (2, 5), (3, 6)];
let (left, right): (Vec<_>, Vec<_>) = z1.iter().cloned().unzip();
assert_eq!((1, 4), (left[0], right[0]));
assert_eq!((2, 5), (left[1], right[1]));
assert_eq!((3, 6), (left[2], right[2]));
}
#[test]
fn test_cmp() {
let x: &[isize] = &[1, 2, 3, 4, 5];
let cmp: &[isize] = &[1, 2, 3, 4, 5];
assert_eq!(&x[..], cmp);
let cmp: &[isize] = &[3, 4, 5];
assert_eq!(&x[2..], cmp);
let cmp: &[isize] = &[1, 2, 3];
assert_eq!(&x[..3], cmp);
let cmp: &[isize] = &[2, 3, 4];
assert_eq!(&x[1..4], cmp);
let x: Vec<isize> = vec![1, 2, 3, 4, 5];
let cmp: &[isize] = &[1, 2, 3, 4, 5];
assert_eq!(&x[..], cmp);
let cmp: &[isize] = &[3, 4, 5];
assert_eq!(&x[2..], cmp);
let cmp: &[isize] = &[1, 2, 3];
assert_eq!(&x[..3], cmp);
let cmp: &[isize] = &[2, 3, 4];
assert_eq!(&x[1..4], cmp);
}
#[test]
fn test_vec_truncate_drop() {
static mut DROPS: u32 = 0;
struct Elem(i32);
impl Drop for Elem {
fn drop(&mut self) {
unsafe {
DROPS += 1;
}
}
}
let mut v = vec![Elem(1), Elem(2), Elem(3), Elem(4), Elem(5)];
assert_eq!(unsafe { DROPS }, 0);
v.truncate(3);
assert_eq!(unsafe { DROPS }, 2);
v.truncate(0);
assert_eq!(unsafe { DROPS }, 5);
}
#[test]
#[should_panic]
fn test_vec_truncate_fail() {
struct BadElem(i32);
impl Drop for BadElem {
fn drop(&mut self) {
let BadElem(ref mut x) = *self;
if *x == 0xbadbeef {
panic!("BadElem panic: 0xbadbeef")
}
}
}
let mut v = vec![BadElem(1), BadElem(2), BadElem(0xbadbeef), BadElem(4)];
v.truncate(0);
}
#[test]
fn test_index() {
let vec = vec![1, 2, 3];
assert!(vec[1] == 2);
}
#[test]
#[should_panic]
fn test_index_out_of_bounds() {
let vec = vec![1, 2, 3];
let _ = vec[3];
}
#[test]
#[should_panic]
fn test_slice_out_of_bounds_1() {
let x = vec![1, 2, 3, 4, 5];
&x[!0..];
}
#[test]
#[should_panic]
fn test_slice_out_of_bounds_2() {
let x = vec![1, 2, 3, 4, 5];
&x[..6];
}
#[test]
#[should_panic]
fn test_slice_out_of_bounds_3() {
let x = vec![1, 2, 3, 4, 5];
&x[!0..4];
}
#[test]
#[should_panic]
fn test_slice_out_of_bounds_4() {
let x = vec![1, 2, 3, 4, 5];
&x[1..6];
}
#[test]
#[should_panic]
fn test_slice_out_of_bounds_5() {
let x = vec![1, 2, 3, 4, 5];
&x[3..2];
}
#[test]
#[should_panic]
fn test_swap_remove_empty() {
let mut vec = Vec::<i32>::new();
vec.swap_remove(0);
}
#[test]
fn test_move_items() {
let vec = vec![1, 2, 3];
let mut vec2 = vec![];
for i in vec {
vec2.push(i);
}
assert_eq!(vec2, [1, 2, 3]);
}
#[test]
fn test_move_items_reverse() {
let vec = vec![1, 2, 3];
let mut vec2 = vec![];
for i in vec.into_iter().rev() {
vec2.push(i);
}
assert_eq!(vec2, [3, 2, 1]);
}
#[test]
fn test_move_items_zero_sized() {
let vec = vec![(), (), ()];
let mut vec2 = vec![];
for i in vec {
vec2.push(i);
}
assert_eq!(vec2, [(), (), ()]);
}
#[test]
fn test_drain_items() {
let mut vec = vec![1, 2, 3];
let mut vec2 = vec![];
for i in vec.drain(..) {
vec2.push(i);
}
assert_eq!(vec, []);
assert_eq!(vec2, [1, 2, 3]);
}
#[test]
fn test_drain_items_reverse() {
let mut vec = vec![1, 2, 3];
let mut vec2 = vec![];
for i in vec.drain(..).rev() {
vec2.push(i);
}
assert_eq!(vec, []);
assert_eq!(vec2, [3, 2, 1]);
}
#[test]
fn test_drain_items_zero_sized() {
let mut vec = vec![(), (), ()];
let mut vec2 = vec![];
for i in vec.drain(..) {
vec2.push(i);
}
assert_eq!(vec, []);
assert_eq!(vec2, [(), (), ()]);
}
#[test]
#[should_panic]
fn test_drain_out_of_bounds() {
let mut v = vec![1, 2, 3, 4, 5];
v.drain(5..6);
}
#[test]
fn test_drain_range() {
let mut v = vec![1, 2, 3, 4, 5];
for _ in v.drain(4..) {}
assert_eq!(v, &[1, 2, 3, 4]);
let mut v: Vec<_> = (1..6).map(|x| x.to_string()).collect();
for _ in v.drain(1..4) {}
assert_eq!(v, &[1.to_string(), 5.to_string()]);
let mut v: Vec<_> = (1..6).map(|x| x.to_string()).collect();
for _ in v.drain(1..4).rev() {}
assert_eq!(v, &[1.to_string(), 5.to_string()]);
let mut v: Vec<_> = vec![(); 5];
for _ in v.drain(1..4).rev() {}
assert_eq!(v, &[(), ()]);
}
#[test]
fn test_drain_inclusive_range() {
let mut v = vec!['a', 'b', 'c', 'd', 'e'];
for _ in v.drain(1..=3) {}
assert_eq!(v, &['a', 'e']);
let mut v: Vec<_> = (0..=5).map(|x| x.to_string()).collect();
for _ in v.drain(1..=5) {}
assert_eq!(v, &["0".to_string()]);
let mut v: Vec<String> = (0..=5).map(|x| x.to_string()).collect();
for _ in v.drain(0..=5) {}
assert_eq!(v, Vec::<String>::new());
let mut v: Vec<_> = (0..=5).map(|x| x.to_string()).collect();
for _ in v.drain(0..=3) {}
assert_eq!(v, &["4".to_string(), "5".to_string()]);
let mut v: Vec<_> = (0..=1).map(|x| x.to_string()).collect();
for _ in v.drain(..=0) {}
assert_eq!(v, &["1".to_string()]);
}
#[test]
fn test_drain_max_vec_size() {
let mut v = Vec::<()>::with_capacity(usize::MAX);
unsafe {
v.set_len(usize::MAX);
}
for _ in v.drain(usize::MAX - 1..) {}
assert_eq!(v.len(), usize::MAX - 1);
let mut v = Vec::<()>::with_capacity(usize::MAX);
unsafe {
v.set_len(usize::MAX);
}
for _ in v.drain(usize::MAX - 1..=usize::MAX - 1) {}
assert_eq!(v.len(), usize::MAX - 1);
}
#[test]
#[should_panic]
fn test_drain_index_overflow() {
let mut v = Vec::<()>::with_capacity(usize::MAX);
unsafe {
v.set_len(usize::MAX);
}
v.drain(0..=usize::MAX);
}
#[test]
#[should_panic]
fn test_drain_inclusive_out_of_bounds() {
let mut v = vec![1, 2, 3, 4, 5];
v.drain(5..=5);
}
#[test]
#[should_panic]
fn test_drain_start_overflow() {
let mut v = vec![1, 2, 3];
v.drain((Excluded(usize::MAX), Included(0)));
}
#[test]
#[should_panic]
fn test_drain_end_overflow() {
let mut v = vec![1, 2, 3];
v.drain((Included(0), Included(usize::MAX)));
}
#[test]
fn test_drain_leak() {
static mut DROPS: i32 = 0;
#[derive(Debug, PartialEq)]
struct D(u32, bool);
impl Drop for D {
fn drop(&mut self) {
unsafe {
DROPS += 1;
}
if self.1 {
panic!("panic in `drop`");
}
}
}
let mut v = vec![
D(0, false),
D(1, false),
D(2, false),
D(3, false),
D(4, true),
D(5, false),
D(6, false),
];
catch_unwind(AssertUnwindSafe(|| {
v.drain(2..=5);
}))
.ok();
assert_eq!(unsafe { DROPS }, 4);
assert_eq!(v, vec![D(0, false), D(1, false), D(6, false),]);
}
#[test]
fn test_splice() {
let mut v = vec![1, 2, 3, 4, 5];
let a = [10, 11, 12];
v.splice(2..4, a.iter().cloned());
assert_eq!(v, &[1, 2, 10, 11, 12, 5]);
v.splice(1..3, Some(20));
assert_eq!(v, &[1, 20, 11, 12, 5]);
}
#[test]
fn test_splice_inclusive_range() {
let mut v = vec![1, 2, 3, 4, 5];
let a = [10, 11, 12];
let t1: Vec<_> = v.splice(2..=3, a.iter().cloned()).collect();
assert_eq!(v, &[1, 2, 10, 11, 12, 5]);
assert_eq!(t1, &[3, 4]);
let t2: Vec<_> = v.splice(1..=2, Some(20)).collect();
assert_eq!(v, &[1, 20, 11, 12, 5]);
assert_eq!(t2, &[2, 10]);
}
#[test]
#[should_panic]
fn test_splice_out_of_bounds() {
let mut v = vec![1, 2, 3, 4, 5];
let a = [10, 11, 12];
v.splice(5..6, a.iter().cloned());
}
#[test]
#[should_panic]
fn test_splice_inclusive_out_of_bounds() {
let mut v = vec![1, 2, 3, 4, 5];
let a = [10, 11, 12];
v.splice(5..=5, a.iter().cloned());
}
#[test]
fn test_splice_items_zero_sized() {
let mut vec = vec![(), (), ()];
let vec2 = vec![];
let t: Vec<_> = vec.splice(1..2, vec2.iter().cloned()).collect();
assert_eq!(vec, &[(), ()]);
assert_eq!(t, &[()]);
}
#[test]
fn test_splice_unbounded() {
let mut vec = vec![1, 2, 3, 4, 5];
let t: Vec<_> = vec.splice(.., None).collect();
assert_eq!(vec, &[]);
assert_eq!(t, &[1, 2, 3, 4, 5]);
}
#[test]
fn test_splice_forget() {
let mut v = vec![1, 2, 3, 4, 5];
let a = [10, 11, 12];
std::mem::forget(v.splice(2..4, a.iter().cloned()));
assert_eq!(v, &[1, 2]);
}
#[test]
fn test_into_boxed_slice() {
let xs = vec![1, 2, 3];
let ys = xs.into_boxed_slice();
assert_eq!(&*ys, [1, 2, 3]);
}
#[test]
fn test_append() {
let mut vec = vec![1, 2, 3];
let mut vec2 = vec![4, 5, 6];
vec.append(&mut vec2);
assert_eq!(vec, [1, 2, 3, 4, 5, 6]);
assert_eq!(vec2, []);
}
#[test]
fn test_split_off() {
let mut vec = vec![1, 2, 3, 4, 5, 6];
let orig_capacity = vec.capacity();
let vec2 = vec.split_off(4);
assert_eq!(vec, [1, 2, 3, 4]);
assert_eq!(vec2, [5, 6]);
assert_eq!(vec.capacity(), orig_capacity);
}
#[test]
fn test_split_off_take_all() {
let mut vec = vec![1, 2, 3, 4, 5, 6];
let orig_ptr = vec.as_ptr();
let orig_capacity = vec.capacity();
let vec2 = vec.split_off(0);
assert_eq!(vec, []);
assert_eq!(vec2, [1, 2, 3, 4, 5, 6]);
assert_eq!(vec.capacity(), orig_capacity);
assert_eq!(vec2.as_ptr(), orig_ptr);
}
#[test]
fn test_into_iter_as_slice() {
let vec = vec!['a', 'b', 'c'];
let mut into_iter = vec.into_iter();
assert_eq!(into_iter.as_slice(), &['a', 'b', 'c']);
let _ = into_iter.next().unwrap();
assert_eq!(into_iter.as_slice(), &['b', 'c']);
let _ = into_iter.next().unwrap();
let _ = into_iter.next().unwrap();
assert_eq!(into_iter.as_slice(), &[]);
}
#[test]
fn test_into_iter_as_mut_slice() {
let vec = vec!['a', 'b', 'c'];
let mut into_iter = vec.into_iter();
assert_eq!(into_iter.as_slice(), &['a', 'b', 'c']);
into_iter.as_mut_slice()[0] = 'x';
into_iter.as_mut_slice()[1] = 'y';
assert_eq!(into_iter.next().unwrap(), 'x');
assert_eq!(into_iter.as_slice(), &['y', 'c']);
}
#[test]
fn test_into_iter_debug() {
let vec = vec!['a', 'b', 'c'];
let into_iter = vec.into_iter();
let debug = format!("{:?}", into_iter);
assert_eq!(debug, "IntoIter(['a', 'b', 'c'])");
}
#[test]
fn test_into_iter_count() {
assert_eq!(vec![1, 2, 3].into_iter().count(), 3);
}
#[test]
fn test_into_iter_clone() {
fn iter_equal<I: Iterator<Item = i32>>(it: I, slice: &[i32]) {
let v: Vec<i32> = it.collect();
assert_eq!(&v[..], slice);
}
let mut it = vec![1, 2, 3].into_iter();
iter_equal(it.clone(), &[1, 2, 3]);
assert_eq!(it.next(), Some(1));
let mut it = it.rev();
iter_equal(it.clone(), &[3, 2]);
assert_eq!(it.next(), Some(3));
iter_equal(it.clone(), &[2]);
assert_eq!(it.next(), Some(2));
iter_equal(it.clone(), &[]);
assert_eq!(it.next(), None);
}
#[test]
fn test_into_iter_leak() {
static mut DROPS: i32 = 0;
struct D(bool);
impl Drop for D {
fn drop(&mut self) {
unsafe {
DROPS += 1;
}
if self.0 {
panic!("panic in `drop`");
}
}
}
let v = vec![D(false), D(true), D(false)];
catch_unwind(move || drop(v.into_iter())).ok();
assert_eq!(unsafe { DROPS }, 3);
}
#[test]
fn test_from_iter_specialization() {
let src: Vec<usize> = vec![0usize; 1];
let srcptr = src.as_ptr();
let sink = src.into_iter().collect::<Vec<_>>();
let sinkptr = sink.as_ptr();
assert_eq!(srcptr, sinkptr);
}
#[test]
fn test_from_iter_partially_drained_in_place_specialization() {
let src: Vec<usize> = vec![0usize; 10];
let srcptr = src.as_ptr();
let mut iter = src.into_iter();
iter.next();
iter.next();
let sink = iter.collect::<Vec<_>>();
let sinkptr = sink.as_ptr();
assert_eq!(srcptr, sinkptr);
}
#[test]
fn test_from_iter_specialization_with_iterator_adapters() {
fn assert_in_place_trait<T: InPlaceIterable>(_: &T) {}
let src: Vec<usize> = vec![0usize; 256];
let srcptr = src.as_ptr();
let iter = src
.into_iter()
.enumerate()
.map(|i| i.0 + i.1)
.zip(std::iter::repeat(1usize))
.map(|(a, b)| a + b)
.map_while(Option::Some)
.peekable()
.skip(1)
.map(|e| std::num::NonZeroUsize::new(e));
assert_in_place_trait(&iter);
let sink = iter.collect::<Vec<_>>();
let sinkptr = sink.as_ptr();
assert_eq!(srcptr, sinkptr as *const usize);
}
#[test]
fn test_from_iter_specialization_head_tail_drop() {
let drop_count: Vec<_> = (0..=2).map(|_| Rc::new(())).collect();
let src: Vec<_> = drop_count.iter().cloned().collect();
let srcptr = src.as_ptr();
let iter = src.into_iter();
let sink: Vec<_> = iter.skip(1).take(1).collect();
let sinkptr = sink.as_ptr();
assert_eq!(srcptr, sinkptr, "specialization was applied");
assert_eq!(Rc::strong_count(&drop_count[0]), 1, "front was dropped");
assert_eq!(Rc::strong_count(&drop_count[1]), 2, "one element was collected");
assert_eq!(Rc::strong_count(&drop_count[2]), 1, "tail was dropped");
assert_eq!(sink.len(), 1);
}
#[test]
fn test_from_iter_specialization_panic_drop() {
let drop_count: Vec<_> = (0..=2).map(|_| Rc::new(())).collect();
let src: Vec<_> = drop_count.iter().cloned().collect();
let iter = src.into_iter();
let _ = std::panic::catch_unwind(AssertUnwindSafe(|| {
let _ = iter
.enumerate()
.filter_map(|(i, e)| {
if i == 1 {
std::panic!("aborting iteration");
}
Some(e)
})
.collect::<Vec<_>>();
}));
assert!(
drop_count.iter().map(Rc::strong_count).all(|count| count == 1),
"all items were dropped once"
);
}
#[test]
fn test_cow_from() {
let borrowed: &[_] = &["borrowed", "(slice)"];
let owned = vec!["owned", "(vec)"];
match (Cow::from(owned.clone()), Cow::from(borrowed)) {
(Cow::Owned(o), Cow::Borrowed(b)) => assert!(o == owned && b == borrowed),
_ => panic!("invalid `Cow::from`"),
}
}
#[test]
fn test_from_cow() {
let borrowed: &[_] = &["borrowed", "(slice)"];
let owned = vec!["owned", "(vec)"];
assert_eq!(Vec::from(Cow::Borrowed(borrowed)), vec!["borrowed", "(slice)"]);
assert_eq!(Vec::from(Cow::Owned(owned)), vec!["owned", "(vec)"]);
}
#[allow(dead_code)]
fn assert_covariance() {
fn drain<'new>(d: Drain<'static, &'static str>) -> Drain<'new, &'new str> {
d
}
fn into_iter<'new>(i: IntoIter<&'static str>) -> IntoIter<&'new str> {
i
}
}
#[test]
fn from_into_inner() {
let vec = vec![1, 2, 3];
let ptr = vec.as_ptr();
let vec = vec.into_iter().collect::<Vec<_>>();
assert_eq!(vec, [1, 2, 3]);
assert_eq!(vec.as_ptr(), ptr);
let ptr = &vec[1] as *const _;
let mut it = vec.into_iter();
it.next().unwrap();
let vec = it.collect::<Vec<_>>();
assert_eq!(vec, [2, 3]);
assert!(ptr != vec.as_ptr());
}
#[test]
fn overaligned_allocations() {
#[repr(align(256))]
struct Foo(usize);
let mut v = vec![Foo(273)];
for i in 0..0x1000 {
v.reserve_exact(i);
assert!(v[0].0 == 273);
assert!(v.as_ptr() as usize & 0xff == 0);
v.shrink_to_fit();
assert!(v[0].0 == 273);
assert!(v.as_ptr() as usize & 0xff == 0);
}
}
#[test]
fn drain_filter_empty() {
let mut vec: Vec<i32> = vec![];
{
let mut iter = vec.drain_filter(|_| true);
assert_eq!(iter.size_hint(), (0, Some(0)));
assert_eq!(iter.next(), None);
assert_eq!(iter.size_hint(), (0, Some(0)));
assert_eq!(iter.next(), None);
assert_eq!(iter.size_hint(), (0, Some(0)));
}
assert_eq!(vec.len(), 0);
assert_eq!(vec, vec![]);
}
#[test]
fn drain_filter_zst() {
let mut vec = vec![(), (), (), (), ()];
let initial_len = vec.len();
let mut count = 0;
{
let mut iter = vec.drain_filter(|_| true);
assert_eq!(iter.size_hint(), (0, Some(initial_len)));
while let Some(_) = iter.next() {
count += 1;
assert_eq!(iter.size_hint(), (0, Some(initial_len - count)));
}
assert_eq!(iter.size_hint(), (0, Some(0)));
assert_eq!(iter.next(), None);
assert_eq!(iter.size_hint(), (0, Some(0)));
}
assert_eq!(count, initial_len);
assert_eq!(vec.len(), 0);
assert_eq!(vec, vec![]);
}
#[test]
fn drain_filter_false() {
let mut vec = vec![1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
let initial_len = vec.len();
let mut count = 0;
{
let mut iter = vec.drain_filter(|_| false);
assert_eq!(iter.size_hint(), (0, Some(initial_len)));
for _ in iter.by_ref() {
count += 1;
}
assert_eq!(iter.size_hint(), (0, Some(0)));
assert_eq!(iter.next(), None);
assert_eq!(iter.size_hint(), (0, Some(0)));
}
assert_eq!(count, 0);
assert_eq!(vec.len(), initial_len);
assert_eq!(vec, vec![1, 2, 3, 4, 5, 6, 7, 8, 9, 10]);
}
#[test]
fn drain_filter_true() {
let mut vec = vec![1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
let initial_len = vec.len();
let mut count = 0;
{
let mut iter = vec.drain_filter(|_| true);
assert_eq!(iter.size_hint(), (0, Some(initial_len)));
while let Some(_) = iter.next() {
count += 1;
assert_eq!(iter.size_hint(), (0, Some(initial_len - count)));
}
assert_eq!(iter.size_hint(), (0, Some(0)));
assert_eq!(iter.next(), None);
assert_eq!(iter.size_hint(), (0, Some(0)));
}
assert_eq!(count, initial_len);
assert_eq!(vec.len(), 0);
assert_eq!(vec, vec![]);
}
#[test]
fn drain_filter_complex() {
{
// [+xxx++++++xxxxx++++x+x++]
let mut vec = vec![
1, 2, 4, 6, 7, 9, 11, 13, 15, 17, 18, 20, 22, 24, 26, 27, 29, 31, 33, 34, 35, 36, 37,
39,
];
let removed = vec.drain_filter(|x| *x % 2 == 0).collect::<Vec<_>>();
assert_eq!(removed.len(), 10);
assert_eq!(removed, vec![2, 4, 6, 18, 20, 22, 24, 26, 34, 36]);
assert_eq!(vec.len(), 14);
assert_eq!(vec, vec![1, 7, 9, 11, 13, 15, 17, 27, 29, 31, 33, 35, 37, 39]);
}
{
// [xxx++++++xxxxx++++x+x++]
let mut vec = vec![
2, 4, 6, 7, 9, 11, 13, 15, 17, 18, 20, 22, 24, 26, 27, 29, 31, 33, 34, 35, 36, 37, 39,
];
let removed = vec.drain_filter(|x| *x % 2 == 0).collect::<Vec<_>>();
assert_eq!(removed.len(), 10);
assert_eq!(removed, vec![2, 4, 6, 18, 20, 22, 24, 26, 34, 36]);
assert_eq!(vec.len(), 13);
assert_eq!(vec, vec![7, 9, 11, 13, 15, 17, 27, 29, 31, 33, 35, 37, 39]);
}
{
// [xxx++++++xxxxx++++x+x]
let mut vec =
vec![2, 4, 6, 7, 9, 11, 13, 15, 17, 18, 20, 22, 24, 26, 27, 29, 31, 33, 34, 35, 36];
let removed = vec.drain_filter(|x| *x % 2 == 0).collect::<Vec<_>>();
assert_eq!(removed.len(), 10);
assert_eq!(removed, vec![2, 4, 6, 18, 20, 22, 24, 26, 34, 36]);
assert_eq!(vec.len(), 11);
assert_eq!(vec, vec![7, 9, 11, 13, 15, 17, 27, 29, 31, 33, 35]);
}
{
// [xxxxxxxxxx+++++++++++]
let mut vec = vec![2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 1, 3, 5, 7, 9, 11, 13, 15, 17, 19];
let removed = vec.drain_filter(|x| *x % 2 == 0).collect::<Vec<_>>();
assert_eq!(removed.len(), 10);
assert_eq!(removed, vec![2, 4, 6, 8, 10, 12, 14, 16, 18, 20]);
assert_eq!(vec.len(), 10);
assert_eq!(vec, vec![1, 3, 5, 7, 9, 11, 13, 15, 17, 19]);
}
{
// [+++++++++++xxxxxxxxxx]
let mut vec = vec![1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20];
let removed = vec.drain_filter(|x| *x % 2 == 0).collect::<Vec<_>>();
assert_eq!(removed.len(), 10);
assert_eq!(removed, vec![2, 4, 6, 8, 10, 12, 14, 16, 18, 20]);
assert_eq!(vec.len(), 10);
assert_eq!(vec, vec![1, 3, 5, 7, 9, 11, 13, 15, 17, 19]);
}
}
// FIXME: re-enable emscripten once it can unwind again
#[test]
#[cfg(not(target_os = "emscripten"))]
fn drain_filter_consumed_panic() {
use std::rc::Rc;
use std::sync::Mutex;
struct Check {
index: usize,
drop_counts: Rc<Mutex<Vec<usize>>>,
}
impl Drop for Check {
fn drop(&mut self) {
self.drop_counts.lock().unwrap()[self.index] += 1;
println!("drop: {}", self.index);
}
}
let check_count = 10;
let drop_counts = Rc::new(Mutex::new(vec![0_usize; check_count]));
let mut data: Vec<Check> = (0..check_count)
.map(|index| Check { index, drop_counts: Rc::clone(&drop_counts) })
.collect();
let _ = std::panic::catch_unwind(move || {
let filter = |c: &mut Check| {
if c.index == 2 {
panic!("panic at index: {}", c.index);
}
// Verify that if the filter could panic again on another element
// that it would not cause a double panic and all elements of the
// vec would still be dropped exactly once.
if c.index == 4 {
panic!("panic at index: {}", c.index);
}
c.index < 6
};
let drain = data.drain_filter(filter);
// NOTE: The DrainFilter is explicitly consumed
drain.for_each(drop);
});
let drop_counts = drop_counts.lock().unwrap();
assert_eq!(check_count, drop_counts.len());
for (index, count) in drop_counts.iter().cloned().enumerate() {
assert_eq!(1, count, "unexpected drop count at index: {} (count: {})", index, count);
}
}
// FIXME: Re-enable emscripten once it can catch panics
#[test]
#[cfg(not(target_os = "emscripten"))]
fn drain_filter_unconsumed_panic() {
use std::rc::Rc;
use std::sync::Mutex;
struct Check {
index: usize,
drop_counts: Rc<Mutex<Vec<usize>>>,
}
impl Drop for Check {
fn drop(&mut self) {
self.drop_counts.lock().unwrap()[self.index] += 1;
println!("drop: {}", self.index);
}
}
let check_count = 10;
let drop_counts = Rc::new(Mutex::new(vec![0_usize; check_count]));
let mut data: Vec<Check> = (0..check_count)
.map(|index| Check { index, drop_counts: Rc::clone(&drop_counts) })
.collect();
let _ = std::panic::catch_unwind(move || {
let filter = |c: &mut Check| {
if c.index == 2 {
panic!("panic at index: {}", c.index);
}
// Verify that if the filter could panic again on another element
// that it would not cause a double panic and all elements of the
// vec would still be dropped exactly once.
if c.index == 4 {
panic!("panic at index: {}", c.index);
}
c.index < 6
};
let _drain = data.drain_filter(filter);
// NOTE: The DrainFilter is dropped without being consumed
});
let drop_counts = drop_counts.lock().unwrap();
assert_eq!(check_count, drop_counts.len());
for (index, count) in drop_counts.iter().cloned().enumerate() {
assert_eq!(1, count, "unexpected drop count at index: {} (count: {})", index, count);
}
}
#[test]
fn drain_filter_unconsumed() {
let mut vec = vec![1, 2, 3, 4];
let drain = vec.drain_filter(|&mut x| x % 2 != 0);
drop(drain);
assert_eq!(vec, [2, 4]);
}
#[test]
fn test_reserve_exact() {
// This is all the same as test_reserve
let mut v = Vec::new();
assert_eq!(v.capacity(), 0);
v.reserve_exact(2);
assert!(v.capacity() >= 2);
for i in 0..16 {
v.push(i);
}
assert!(v.capacity() >= 16);
v.reserve_exact(16);
assert!(v.capacity() >= 32);
v.push(16);
v.reserve_exact(16);
assert!(v.capacity() >= 33)
}
#[test]
#[cfg_attr(miri, ignore)] // Miri does not support signalling OOM
#[cfg_attr(target_os = "android", ignore)] // Android used in CI has a broken dlmalloc
fn test_try_reserve() {
// These are the interesting cases:
// * exactly isize::MAX should never trigger a CapacityOverflow (can be OOM)
// * > isize::MAX should always fail
// * On 16/32-bit should CapacityOverflow
// * On 64-bit should OOM
// * overflow may trigger when adding `len` to `cap` (in number of elements)
// * overflow may trigger when multiplying `new_cap` by size_of::<T> (to get bytes)
const MAX_CAP: usize = isize::MAX as usize;
const MAX_USIZE: usize = usize::MAX;
// On 16/32-bit, we check that allocations don't exceed isize::MAX,
// on 64-bit, we assume the OS will give an OOM for such a ridiculous size.
// Any platform that succeeds for these requests is technically broken with
// ptr::offset because LLVM is the worst.
let guards_against_isize = usize::BITS < 64;
{
// Note: basic stuff is checked by test_reserve
let mut empty_bytes: Vec<u8> = Vec::new();
// Check isize::MAX doesn't count as an overflow
if let Err(CapacityOverflow) = empty_bytes.try_reserve(MAX_CAP) {
panic!("isize::MAX shouldn't trigger an overflow!");
}
// Play it again, frank! (just to be sure)
if let Err(CapacityOverflow) = empty_bytes.try_reserve(MAX_CAP) {
panic!("isize::MAX shouldn't trigger an overflow!");
}
if guards_against_isize {
// Check isize::MAX + 1 does count as overflow
if let Err(CapacityOverflow) = empty_bytes.try_reserve(MAX_CAP + 1) {
} else {
panic!("isize::MAX + 1 should trigger an overflow!")
}
// Check usize::MAX does count as overflow
if let Err(CapacityOverflow) = empty_bytes.try_reserve(MAX_USIZE) {
} else {
panic!("usize::MAX should trigger an overflow!")
}
} else {
// Check isize::MAX + 1 is an OOM
if let Err(AllocError { .. }) = empty_bytes.try_reserve(MAX_CAP + 1) {
} else {
panic!("isize::MAX + 1 should trigger an OOM!")
}
// Check usize::MAX is an OOM
if let Err(AllocError { .. }) = empty_bytes.try_reserve(MAX_USIZE) {
} else {
panic!("usize::MAX should trigger an OOM!")
}
}
}
{
// Same basic idea, but with non-zero len
let mut ten_bytes: Vec<u8> = vec![1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
if let Err(CapacityOverflow) = ten_bytes.try_reserve(MAX_CAP - 10) {
panic!("isize::MAX shouldn't trigger an overflow!");
}
if let Err(CapacityOverflow) = ten_bytes.try_reserve(MAX_CAP - 10) {
panic!("isize::MAX shouldn't trigger an overflow!");
}
if guards_against_isize {
if let Err(CapacityOverflow) = ten_bytes.try_reserve(MAX_CAP - 9) {
} else {
panic!("isize::MAX + 1 should trigger an overflow!");
}
} else {
if let Err(AllocError { .. }) = ten_bytes.try_reserve(MAX_CAP - 9) {
} else {
panic!("isize::MAX + 1 should trigger an OOM!")
}
}
// Should always overflow in the add-to-len
if let Err(CapacityOverflow) = ten_bytes.try_reserve(MAX_USIZE) {
} else {
panic!("usize::MAX should trigger an overflow!")
}
}
{
// Same basic idea, but with interesting type size
let mut ten_u32s: Vec<u32> = vec![1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
if let Err(CapacityOverflow) = ten_u32s.try_reserve(MAX_CAP / 4 - 10) {
panic!("isize::MAX shouldn't trigger an overflow!");
}
if let Err(CapacityOverflow) = ten_u32s.try_reserve(MAX_CAP / 4 - 10) {
panic!("isize::MAX shouldn't trigger an overflow!");
}
if guards_against_isize {
if let Err(CapacityOverflow) = ten_u32s.try_reserve(MAX_CAP / 4 - 9) {
} else {
panic!("isize::MAX + 1 should trigger an overflow!");
}
} else {
if let Err(AllocError { .. }) = ten_u32s.try_reserve(MAX_CAP / 4 - 9) {
} else {
panic!("isize::MAX + 1 should trigger an OOM!")
}
}
// Should fail in the mul-by-size
if let Err(CapacityOverflow) = ten_u32s.try_reserve(MAX_USIZE - 20) {
} else {
panic!("usize::MAX should trigger an overflow!");
}
}
}
#[test]
#[cfg_attr(miri, ignore)] // Miri does not support signalling OOM
#[cfg_attr(target_os = "android", ignore)] // Android used in CI has a broken dlmalloc
fn test_try_reserve_exact() {
// This is exactly the same as test_try_reserve with the method changed.
// See that test for comments.
const MAX_CAP: usize = isize::MAX as usize;
const MAX_USIZE: usize = usize::MAX;
let guards_against_isize = size_of::<usize>() < 8;
{
let mut empty_bytes: Vec<u8> = Vec::new();
if let Err(CapacityOverflow) = empty_bytes.try_reserve_exact(MAX_CAP) {
panic!("isize::MAX shouldn't trigger an overflow!");
}
if let Err(CapacityOverflow) = empty_bytes.try_reserve_exact(MAX_CAP) {
panic!("isize::MAX shouldn't trigger an overflow!");
}
if guards_against_isize {
if let Err(CapacityOverflow) = empty_bytes.try_reserve_exact(MAX_CAP + 1) {
} else {
panic!("isize::MAX + 1 should trigger an overflow!")
}
if let Err(CapacityOverflow) = empty_bytes.try_reserve_exact(MAX_USIZE) {
} else {
panic!("usize::MAX should trigger an overflow!")
}
} else {
if let Err(AllocError { .. }) = empty_bytes.try_reserve_exact(MAX_CAP + 1) {
} else {
panic!("isize::MAX + 1 should trigger an OOM!")
}
if let Err(AllocError { .. }) = empty_bytes.try_reserve_exact(MAX_USIZE) {
} else {
panic!("usize::MAX should trigger an OOM!")
}
}
}
{
let mut ten_bytes: Vec<u8> = vec![1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
if let Err(CapacityOverflow) = ten_bytes.try_reserve_exact(MAX_CAP - 10) {
panic!("isize::MAX shouldn't trigger an overflow!");
}
if let Err(CapacityOverflow) = ten_bytes.try_reserve_exact(MAX_CAP - 10) {
panic!("isize::MAX shouldn't trigger an overflow!");
}
if guards_against_isize {
if let Err(CapacityOverflow) = ten_bytes.try_reserve_exact(MAX_CAP - 9) {
} else {
panic!("isize::MAX + 1 should trigger an overflow!");
}
} else {
if let Err(AllocError { .. }) = ten_bytes.try_reserve_exact(MAX_CAP - 9) {
} else {
panic!("isize::MAX + 1 should trigger an OOM!")
}
}
if let Err(CapacityOverflow) = ten_bytes.try_reserve_exact(MAX_USIZE) {
} else {
panic!("usize::MAX should trigger an overflow!")
}
}
{
let mut ten_u32s: Vec<u32> = vec![1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
if let Err(CapacityOverflow) = ten_u32s.try_reserve_exact(MAX_CAP / 4 - 10) {
panic!("isize::MAX shouldn't trigger an overflow!");
}
if let Err(CapacityOverflow) = ten_u32s.try_reserve_exact(MAX_CAP / 4 - 10) {
panic!("isize::MAX shouldn't trigger an overflow!");
}
if guards_against_isize {
if let Err(CapacityOverflow) = ten_u32s.try_reserve_exact(MAX_CAP / 4 - 9) {
} else {
panic!("isize::MAX + 1 should trigger an overflow!");
}
} else {
if let Err(AllocError { .. }) = ten_u32s.try_reserve_exact(MAX_CAP / 4 - 9) {
} else {
panic!("isize::MAX + 1 should trigger an OOM!")
}
}
if let Err(CapacityOverflow) = ten_u32s.try_reserve_exact(MAX_USIZE - 20) {
} else {
panic!("usize::MAX should trigger an overflow!")
}
}
}
#[test]
fn test_stable_pointers() {
/// Pull an element from the iterator, then drop it.
/// Useful to cover both the `next` and `drop` paths of an iterator.
fn next_then_drop<I: Iterator>(mut i: I) {
i.next().unwrap();
drop(i);
}
// Test that, if we reserved enough space, adding and removing elements does not
// invalidate references into the vector (such as `v0`). This test also
// runs in Miri, which would detect such problems.
// Note that this test does *not* constitute a stable guarantee that all these functions do not
// reallocate! Only what is explicitly documented at
// <https://doc.rust-lang.org/nightly/std/vec/struct.Vec.html#guarantees> is stably guaranteed.
let mut v = Vec::with_capacity(128);
v.push(13);
// Laundering the lifetime -- we take care that `v` does not reallocate, so that's okay.
let v0 = &mut v[0];
let v0 = unsafe { &mut *(v0 as *mut _) };
// Now do a bunch of things and occasionally use `v0` again to assert it is still valid.
// Pushing/inserting and popping/removing
v.push(1);
v.push(2);
v.insert(1, 1);
assert_eq!(*v0, 13);
v.remove(1);
v.pop().unwrap();
assert_eq!(*v0, 13);
v.push(1);
v.swap_remove(1);
assert_eq!(v.len(), 2);
v.swap_remove(1); // swap_remove the last element
assert_eq!(*v0, 13);
// Appending
v.append(&mut vec![27, 19]);
assert_eq!(*v0, 13);
// Extending
v.extend_from_slice(&[1, 2]);
v.extend(&[1, 2]); // `slice::Iter` (with `T: Copy`) specialization
v.extend(vec![2, 3]); // `vec::IntoIter` specialization
v.extend(std::iter::once(3)); // `TrustedLen` specialization
v.extend(std::iter::empty::<i32>()); // `TrustedLen` specialization with empty iterator
v.extend(std::iter::once(3).filter(|_| true)); // base case
v.extend(std::iter::once(&3)); // `cloned` specialization
assert_eq!(*v0, 13);
// Truncation
v.truncate(2);
assert_eq!(*v0, 13);
// Resizing
v.resize_with(v.len() + 10, || 42);
assert_eq!(*v0, 13);
v.resize_with(2, || panic!());
assert_eq!(*v0, 13);
// No-op reservation
v.reserve(32);
v.reserve_exact(32);
assert_eq!(*v0, 13);
// Partial draining
v.resize_with(10, || 42);
next_then_drop(v.drain(5..));
assert_eq!(*v0, 13);
// Splicing
v.resize_with(10, || 42);
next_then_drop(v.splice(5.., vec![1, 2, 3, 4, 5])); // empty tail after range
assert_eq!(*v0, 13);
next_then_drop(v.splice(5..8, vec![1])); // replacement is smaller than original range
assert_eq!(*v0, 13);
next_then_drop(v.splice(5..6, vec![1; 10].into_iter().filter(|_| true))); // lower bound not exact
assert_eq!(*v0, 13);
// Smoke test that would fire even outside Miri if an actual relocation happened.
*v0 -= 13;
assert_eq!(v[0], 0);
}
// https://github.com/rust-lang/rust/pull/49496 introduced specialization based on:
//
// ```
// unsafe impl<T: ?Sized> IsZero for *mut T {
// fn is_zero(&self) -> bool {
// (*self).is_null()
// }
// }
// ```
//
// … to call `RawVec::with_capacity_zeroed` for creating `Vec<*mut T>`,
// which is incorrect for fat pointers since `<*mut T>::is_null` only looks at the data component.
// That is, a fat pointer can be “null” without being made entirely of zero bits.
#[test]
fn vec_macro_repeating_null_raw_fat_pointer() {
let raw_dyn = &mut (|| ()) as &mut dyn Fn() as *mut dyn Fn();
let vtable = dbg!(ptr_metadata(raw_dyn));
let null_raw_dyn = ptr_from_raw_parts(std::ptr::null_mut(), vtable);
assert!(null_raw_dyn.is_null());
let vec = vec![null_raw_dyn; 1];
dbg!(ptr_metadata(vec[0]));
assert!(vec[0] == null_raw_dyn);
// Polyfill for https://github.com/rust-lang/rfcs/pull/2580
fn ptr_metadata(ptr: *mut dyn Fn()) -> *mut () {
unsafe { std::mem::transmute::<*mut dyn Fn(), DynRepr>(ptr).vtable }
}
fn ptr_from_raw_parts(data: *mut (), vtable: *mut ()) -> *mut dyn Fn() {
unsafe { std::mem::transmute::<DynRepr, *mut dyn Fn()>(DynRepr { data, vtable }) }
}
#[repr(C)]
struct DynRepr {
data: *mut (),
vtable: *mut (),
}
}
// This test will likely fail if you change the capacities used in
// `RawVec::grow_amortized`.
#[test]
fn test_push_growth_strategy() {
// If the element size is 1, we jump from 0 to 8, then double.
{
let mut v1: Vec<u8> = vec![];
assert_eq!(v1.capacity(), 0);
for _ in 0..8 {
v1.push(0);
assert_eq!(v1.capacity(), 8);
}
for _ in 8..16 {
v1.push(0);
assert_eq!(v1.capacity(), 16);
}
for _ in 16..32 {
v1.push(0);
assert_eq!(v1.capacity(), 32);
}
for _ in 32..64 {
v1.push(0);
assert_eq!(v1.capacity(), 64);
}
}
// If the element size is 2..=1024, we jump from 0 to 4, then double.
{
let mut v2: Vec<u16> = vec![];
let mut v1024: Vec<[u8; 1024]> = vec![];
assert_eq!(v2.capacity(), 0);
assert_eq!(v1024.capacity(), 0);
for _ in 0..4 {
v2.push(0);
v1024.push([0; 1024]);
assert_eq!(v2.capacity(), 4);
assert_eq!(v1024.capacity(), 4);
}
for _ in 4..8 {
v2.push(0);
v1024.push([0; 1024]);
assert_eq!(v2.capacity(), 8);
assert_eq!(v1024.capacity(), 8);
}
for _ in 8..16 {
v2.push(0);
v1024.push([0; 1024]);
assert_eq!(v2.capacity(), 16);
assert_eq!(v1024.capacity(), 16);
}
for _ in 16..32 {
v2.push(0);
v1024.push([0; 1024]);
assert_eq!(v2.capacity(), 32);
assert_eq!(v1024.capacity(), 32);
}
for _ in 32..64 {
v2.push(0);
v1024.push([0; 1024]);
assert_eq!(v2.capacity(), 64);
assert_eq!(v1024.capacity(), 64);
}
}
// If the element size is > 1024, we jump from 0 to 1, then double.
{
let mut v1025: Vec<[u8; 1025]> = vec![];
assert_eq!(v1025.capacity(), 0);
for _ in 0..1 {
v1025.push([0; 1025]);
assert_eq!(v1025.capacity(), 1);
}
for _ in 1..2 {
v1025.push([0; 1025]);
assert_eq!(v1025.capacity(), 2);
}
for _ in 2..4 {
v1025.push([0; 1025]);
assert_eq!(v1025.capacity(), 4);
}
for _ in 4..8 {
v1025.push([0; 1025]);
assert_eq!(v1025.capacity(), 8);
}
for _ in 8..16 {
v1025.push([0; 1025]);
assert_eq!(v1025.capacity(), 16);
}
for _ in 16..32 {
v1025.push([0; 1025]);
assert_eq!(v1025.capacity(), 32);
}
for _ in 32..64 {
v1025.push([0; 1025]);
assert_eq!(v1025.capacity(), 64);
}
}
}
macro_rules! generate_assert_eq_vec_and_prim {
($name:ident<$B:ident>($type:ty)) => {
fn $name<A: PartialEq<$B> + Debug, $B: Debug>(a: Vec<A>, b: $type) {
assert!(a == b);
assert_eq!(a, b);
}
};
}
generate_assert_eq_vec_and_prim! { assert_eq_vec_and_slice <B>(&[B]) }
generate_assert_eq_vec_and_prim! { assert_eq_vec_and_array_3<B>([B; 3]) }
#[test]
fn partialeq_vec_and_prim() {
assert_eq_vec_and_slice(vec![1, 2, 3], &[1, 2, 3]);
assert_eq_vec_and_array_3(vec![1, 2, 3], [1, 2, 3]);
}
macro_rules! assert_partial_eq_valid {
($a2:expr, $a3:expr; $b2:expr, $b3: expr) => {
assert!($a2 == $b2);
assert!($a2 != $b3);
assert!($a3 != $b2);
assert!($a3 == $b3);
assert_eq!($a2, $b2);
assert_ne!($a2, $b3);
assert_ne!($a3, $b2);
assert_eq!($a3, $b3);
};
}
#[test]
fn partialeq_vec_full() {
let vec2: Vec<_> = vec![1, 2];
let vec3: Vec<_> = vec![1, 2, 3];
let slice2: &[_] = &[1, 2];
let slice3: &[_] = &[1, 2, 3];
let slicemut2: &[_] = &mut [1, 2];
let slicemut3: &[_] = &mut [1, 2, 3];
let array2: [_; 2] = [1, 2];
let array3: [_; 3] = [1, 2, 3];
let arrayref2: &[_; 2] = &[1, 2];
let arrayref3: &[_; 3] = &[1, 2, 3];
assert_partial_eq_valid!(vec2,vec3; vec2,vec3);
assert_partial_eq_valid!(vec2,vec3; slice2,slice3);
assert_partial_eq_valid!(vec2,vec3; slicemut2,slicemut3);
assert_partial_eq_valid!(slice2,slice3; vec2,vec3);
assert_partial_eq_valid!(slicemut2,slicemut3; vec2,vec3);
assert_partial_eq_valid!(vec2,vec3; array2,array3);
assert_partial_eq_valid!(vec2,vec3; arrayref2,arrayref3);
assert_partial_eq_valid!(vec2,vec3; arrayref2[..],arrayref3[..]);
}
#[test]
fn test_vec_cycle() {
#[derive(Debug)]
struct C<'a> {
v: Vec<Cell<Option<&'a C<'a>>>>,
}
impl<'a> C<'a> {
fn new() -> C<'a> {
C { v: Vec::new() }
}
}
let mut c1 = C::new();
let mut c2 = C::new();
let mut c3 = C::new();
// Push
c1.v.push(Cell::new(None));
c1.v.push(Cell::new(None));
c2.v.push(Cell::new(None));
c2.v.push(Cell::new(None));
c3.v.push(Cell::new(None));
c3.v.push(Cell::new(None));
// Set
c1.v[0].set(Some(&c2));
c1.v[1].set(Some(&c3));
c2.v[0].set(Some(&c2));
c2.v[1].set(Some(&c3));
c3.v[0].set(Some(&c1));
c3.v[1].set(Some(&c2));
}
#[test]
fn test_vec_cycle_wrapped() {
struct Refs<'a> {
v: Vec<Cell<Option<&'a C<'a>>>>,
}
struct C<'a> {
refs: Refs<'a>,
}
impl<'a> Refs<'a> {
fn new() -> Refs<'a> {
Refs { v: Vec::new() }
}
}
impl<'a> C<'a> {
fn new() -> C<'a> {
C { refs: Refs::new() }
}
}
let mut c1 = C::new();
let mut c2 = C::new();
let mut c3 = C::new();
c1.refs.v.push(Cell::new(None));
c1.refs.v.push(Cell::new(None));
c2.refs.v.push(Cell::new(None));
c2.refs.v.push(Cell::new(None));
c3.refs.v.push(Cell::new(None));
c3.refs.v.push(Cell::new(None));
c1.refs.v[0].set(Some(&c2));
c1.refs.v[1].set(Some(&c3));
c2.refs.v[0].set(Some(&c2));
c2.refs.v[1].set(Some(&c3));
c3.refs.v[0].set(Some(&c1));
c3.refs.v[1].set(Some(&c2));
}
#[test]
fn test_zero_sized_vec_push() {
const N: usize = 8;
for len in 0..N {
let mut tester = Vec::with_capacity(len);
assert_eq!(tester.len(), 0);
assert!(tester.capacity() >= len);
for _ in 0..len {
tester.push(());
}
assert_eq!(tester.len(), len);
assert_eq!(tester.iter().count(), len);
tester.clear();
}
}
#[test]
fn test_vec_macro_repeat() {
assert_eq!(vec![1; 3], vec![1, 1, 1]);
assert_eq!(vec![1; 2], vec![1, 1]);
assert_eq!(vec![1; 1], vec![1]);
assert_eq!(vec![1; 0], vec![]);
// from_elem syntax (see RFC 832)
let el = Box::new(1);
let n = 3;
assert_eq!(vec![el; n], vec![Box::new(1), Box::new(1), Box::new(1)]);
}
#[test]
fn test_vec_swap() {
let mut a: Vec<isize> = vec![0, 1, 2, 3, 4, 5, 6];
a.swap(2, 4);
assert_eq!(a[2], 4);
assert_eq!(a[4], 2);
let mut n = 42;
swap(&mut n, &mut a[0]);
assert_eq!(a[0], 42);
assert_eq!(n, 0);
}
#[test]
fn test_extend_from_within_spec() {
#[derive(Copy)]
struct CopyOnly;
impl Clone for CopyOnly {
fn clone(&self) -> Self {
panic!("extend_from_within must use specialization on copy");
}
}
vec![CopyOnly, CopyOnly].extend_from_within(..);
}
#[test]
fn test_extend_from_within_clone() {
let mut v = vec![String::from("sssss"), String::from("12334567890"), String::from("c")];
v.extend_from_within(1..);
assert_eq!(v, ["sssss", "12334567890", "c", "12334567890", "c"]);
}
#[test]
fn test_extend_from_within_complete_rande() {
let mut v = vec![0, 1, 2, 3];
v.extend_from_within(..);
assert_eq!(v, [0, 1, 2, 3, 0, 1, 2, 3]);
}
#[test]
fn test_extend_from_within_empty_rande() {
let mut v = vec![0, 1, 2, 3];
v.extend_from_within(1..1);
assert_eq!(v, [0, 1, 2, 3]);
}
#[test]
#[should_panic]
fn test_extend_from_within_out_of_rande() {
let mut v = vec![0, 1];
v.extend_from_within(..3);
}
#[test]
fn test_extend_from_within_zst() {
let mut v = vec![(); 8];
v.extend_from_within(3..7);
assert_eq!(v, [(); 12]);
}
#[test]
fn test_extend_from_within_empty_vec() {
let mut v = Vec::<i32>::new();
v.extend_from_within(..);
assert_eq!(v, []);
}
#[test]
fn test_extend_from_within() {
let mut v = vec![String::from("a"), String::from("b"), String::from("c")];
v.extend_from_within(1..=2);
v.extend_from_within(..=1);
assert_eq!(v, ["a", "b", "c", "b", "c", "a", "b"]);
}