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use ecow::{eco_vec, EcoVec};
// Guarding against something like:
// https://github.com/servo/rust-smallvec/issues/96 aka RUSTSEC-2018-0003
// If length isn't updated defensively then a panic when iterating could
// double-free a value.
#[test]
#[should_panic(expected = "Panic on next")]
fn panicky_iterator_unwinds_correctly() {
struct PanicIter;
impl Iterator for PanicIter {
type Item = u32;
fn size_hint(&self) -> (usize, Option<usize>) {
(1, None)
}
fn next(&mut self) -> Option<Self::Item> {
panic!("Panic on next");
}
}
let mut v = eco_vec![1, 2, 3];
v.extend(PanicIter);
}
// Guarding against something like:
// https://github.com/servo/rust-smallvec/issues/252 aka RUSTSEC-2021-0003
// size_hint should only be treated as a hint, nothing more.
#[test]
fn small_size_hint_is_fine() {
let mut v = EcoVec::new();
v.push(123);
let iter = (0u8..=255).filter(|n| n % 2 == 0);
assert_eq!(iter.size_hint().0, 0);
v.extend(iter);
assert_eq!(
v,
core::iter::once(123)
.chain((0u8..=255).filter(|n| n % 2 == 0))
.collect::<Vec<_>>()
);
}
// Guarding against something like:
// https://github.com/Alexhuszagh/rust-stackvector/issues/2 aka RUSTSEC-2021-0048
// size_hint should only be treated as a hint, nothing more.
#[test]
fn wacky_size_hint_is_fine() {
struct IncorrectIterator(core::iter::Take<core::iter::Repeat<u8>>);
impl IncorrectIterator {
pub fn new() -> Self {
IncorrectIterator(core::iter::repeat(1).take(20))
}
}
impl Iterator for IncorrectIterator {
type Item = u8;
fn next(&mut self) -> Option<Self::Item> {
self.0.next()
}
fn size_hint(&self) -> (usize, Option<usize>) {
(20, Some(0))
}
}
let mut v = EcoVec::new();
v.extend(IncorrectIterator::new());
assert_eq!(v, IncorrectIterator::new().collect::<Vec<_>>())
}
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