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use crate::{smallvec, SmallVec};
use std::iter::FromIterator;
use alloc::borrow::ToOwned;
use alloc::boxed::Box;
use alloc::rc::Rc;
use alloc::{vec, vec::Vec};
#[test]
pub fn test_zero() {
let mut v = SmallVec::<[_; 0]>::new();
assert!(!v.spilled());
v.push(0usize);
assert!(v.spilled());
assert_eq!(&*v, &[0]);
}
// We heap allocate all these strings so that double frees will show up under valgrind.
#[test]
pub fn test_inline() {
let mut v = SmallVec::<[_; 16]>::new();
v.push("hello".to_owned());
v.push("there".to_owned());
assert_eq!(&*v, &["hello".to_owned(), "there".to_owned(),][..]);
}
#[test]
pub fn test_spill() {
let mut v = SmallVec::<[_; 2]>::new();
v.push("hello".to_owned());
assert_eq!(v[0], "hello");
v.push("there".to_owned());
v.push("burma".to_owned());
assert_eq!(v[0], "hello");
v.push("shave".to_owned());
assert_eq!(
&*v,
&[
"hello".to_owned(),
"there".to_owned(),
"burma".to_owned(),
"shave".to_owned(),
][..]
);
}
#[test]
pub fn test_double_spill() {
let mut v = SmallVec::<[_; 2]>::new();
v.push("hello".to_owned());
v.push("there".to_owned());
v.push("burma".to_owned());
v.push("shave".to_owned());
v.push("hello".to_owned());
v.push("there".to_owned());
v.push("burma".to_owned());
v.push("shave".to_owned());
assert_eq!(
&*v,
&[
"hello".to_owned(),
"there".to_owned(),
"burma".to_owned(),
"shave".to_owned(),
"hello".to_owned(),
"there".to_owned(),
"burma".to_owned(),
"shave".to_owned(),
][..]
);
}
#[test]
fn issue_4() {
SmallVec::<[Box<u32>; 2]>::new();
}
#[test]
fn issue_5() {
assert!(Some(SmallVec::<[&u32; 2]>::new()).is_some());
}
#[test]
fn test_with_capacity() {
let v: SmallVec<[u8; 3]> = SmallVec::with_capacity(1);
assert!(v.is_empty());
assert!(!v.spilled());
assert_eq!(v.capacity(), 3);
let v: SmallVec<[u8; 3]> = SmallVec::with_capacity(10);
assert!(v.is_empty());
assert!(v.spilled());
assert_eq!(v.capacity(), 10);
}
#[test]
fn drain() {
let mut v: SmallVec<[u8; 2]> = SmallVec::new();
v.push(3);
assert_eq!(v.drain(..).collect::<Vec<_>>(), &[3]);
// spilling the vec
v.push(3);
v.push(4);
v.push(5);
let old_capacity = v.capacity();
assert_eq!(v.drain(1..).collect::<Vec<_>>(), &[4, 5]);
// drain should not change the capacity
assert_eq!(v.capacity(), old_capacity);
// Exercise the tail-shifting code when in the inline state
// This has the potential to produce UB due to aliasing
let mut v: SmallVec<[u8; 2]> = SmallVec::new();
v.push(1);
v.push(2);
assert_eq!(v.drain(..1).collect::<Vec<_>>(), &[1]);
}
#[test]
fn drain_rev() {
let mut v: SmallVec<[u8; 2]> = SmallVec::new();
v.push(3);
assert_eq!(v.drain(..).rev().collect::<Vec<_>>(), &[3]);
// spilling the vec
v.push(3);
v.push(4);
v.push(5);
assert_eq!(v.drain(..).rev().collect::<Vec<_>>(), &[5, 4, 3]);
}
#[test]
fn drain_forget() {
let mut v: SmallVec<[u8; 1]> = smallvec![0, 1, 2, 3, 4, 5, 6, 7];
std::mem::forget(v.drain(2..5));
assert_eq!(v.len(), 2);
}
#[test]
fn into_iter() {
let mut v: SmallVec<[u8; 2]> = SmallVec::new();
v.push(3);
assert_eq!(v.into_iter().collect::<Vec<_>>(), &[3]);
// spilling the vec
let mut v: SmallVec<[u8; 2]> = SmallVec::new();
v.push(3);
v.push(4);
v.push(5);
assert_eq!(v.into_iter().collect::<Vec<_>>(), &[3, 4, 5]);
}
#[test]
fn into_iter_rev() {
let mut v: SmallVec<[u8; 2]> = SmallVec::new();
v.push(3);
assert_eq!(v.into_iter().rev().collect::<Vec<_>>(), &[3]);
// spilling the vec
let mut v: SmallVec<[u8; 2]> = SmallVec::new();
v.push(3);
v.push(4);
v.push(5);
assert_eq!(v.into_iter().rev().collect::<Vec<_>>(), &[5, 4, 3]);
}
#[test]
fn into_iter_drop() {
use std::cell::Cell;
struct DropCounter<'a>(&'a Cell<i32>);
impl<'a> Drop for DropCounter<'a> {
fn drop(&mut self) {
self.0.set(self.0.get() + 1);
}
}
{
let cell = Cell::new(0);
let mut v: SmallVec<[DropCounter<'_>; 2]> = SmallVec::new();
v.push(DropCounter(&cell));
v.into_iter();
assert_eq!(cell.get(), 1);
}
{
let cell = Cell::new(0);
let mut v: SmallVec<[DropCounter<'_>; 2]> = SmallVec::new();
v.push(DropCounter(&cell));
v.push(DropCounter(&cell));
assert!(v.into_iter().next().is_some());
assert_eq!(cell.get(), 2);
}
{
let cell = Cell::new(0);
let mut v: SmallVec<[DropCounter<'_>; 2]> = SmallVec::new();
v.push(DropCounter(&cell));
v.push(DropCounter(&cell));
v.push(DropCounter(&cell));
assert!(v.into_iter().next().is_some());
assert_eq!(cell.get(), 3);
}
{
let cell = Cell::new(0);
let mut v: SmallVec<[DropCounter<'_>; 2]> = SmallVec::new();
v.push(DropCounter(&cell));
v.push(DropCounter(&cell));
v.push(DropCounter(&cell));
{
let mut it = v.into_iter();
assert!(it.next().is_some());
assert!(it.next_back().is_some());
}
assert_eq!(cell.get(), 3);
}
}
#[test]
fn test_capacity() {
let mut v: SmallVec<[u8; 2]> = SmallVec::new();
v.reserve(1);
assert_eq!(v.capacity(), 2);
assert!(!v.spilled());
v.reserve_exact(0x100);
assert!(v.capacity() >= 0x100);
v.push(0);
v.push(1);
v.push(2);
v.push(3);
v.shrink_to_fit();
assert!(v.capacity() < 0x100);
}
#[test]
fn test_truncate() {
let mut v: SmallVec<[Box<u8>; 8]> = SmallVec::new();
for x in 0..8 {
v.push(Box::new(x));
}
v.truncate(4);
assert_eq!(v.len(), 4);
assert!(!v.spilled());
assert_eq!(*v.swap_remove(1), 1);
assert_eq!(*v.remove(1), 3);
v.insert(1, Box::new(3));
assert_eq!(&v.iter().map(|v| **v).collect::<Vec<_>>(), &[0, 3, 2]);
}
#[test]
fn test_insert_many() {
let mut v: SmallVec<[u8; 8]> = SmallVec::new();
for x in 0..4 {
v.push(x);
}
assert_eq!(v.len(), 4);
v.insert_many(1, [5, 6].iter().cloned());
assert_eq!(
&v.iter().map(|v| *v).collect::<Vec<_>>(),
&[0, 5, 6, 1, 2, 3]
);
}
struct MockHintIter<T: Iterator> {
x: T,
hint: usize,
}
impl<T: Iterator> Iterator for MockHintIter<T> {
type Item = T::Item;
fn next(&mut self) -> Option<Self::Item> {
self.x.next()
}
fn size_hint(&self) -> (usize, Option<usize>) {
(self.hint, None)
}
}
#[test]
fn test_insert_many_short_hint() {
let mut v: SmallVec<[u8; 8]> = SmallVec::new();
for x in 0..4 {
v.push(x);
}
assert_eq!(v.len(), 4);
v.insert_many(
1,
MockHintIter {
x: [5, 6].iter().cloned(),
hint: 5,
},
);
assert_eq!(
&v.iter().map(|v| *v).collect::<Vec<_>>(),
&[0, 5, 6, 1, 2, 3]
);
}
#[test]
fn test_insert_many_long_hint() {
let mut v: SmallVec<[u8; 8]> = SmallVec::new();
for x in 0..4 {
v.push(x);
}
assert_eq!(v.len(), 4);
v.insert_many(
1,
MockHintIter {
x: [5, 6].iter().cloned(),
hint: 1,
},
);
assert_eq!(
&v.iter().map(|v| *v).collect::<Vec<_>>(),
&[0, 5, 6, 1, 2, 3]
);
}
mod insert_many_panic {
use crate::{smallvec, SmallVec};
use alloc::boxed::Box;
struct PanicOnDoubleDrop {
dropped: Box<bool>,
}
impl PanicOnDoubleDrop {
fn new() -> Self {
Self {
dropped: Box::new(false),
}
}
}
impl Drop for PanicOnDoubleDrop {
fn drop(&mut self) {
assert!(!*self.dropped, "already dropped");
*self.dropped = true;
}
}
/// Claims to yield `hint` items, but actually yields `count`, then panics.
struct BadIter {
hint: usize,
count: usize,
}
impl Iterator for BadIter {
type Item = PanicOnDoubleDrop;
fn size_hint(&self) -> (usize, Option<usize>) {
(self.hint, None)
}
fn next(&mut self) -> Option<Self::Item> {
if self.count == 0 {
panic!()
}
self.count -= 1;
Some(PanicOnDoubleDrop::new())
}
}
#[test]
fn panic_early_at_start() {
let mut vec: SmallVec<[PanicOnDoubleDrop; 0]> =
smallvec![PanicOnDoubleDrop::new(), PanicOnDoubleDrop::new(),];
let result = ::std::panic::catch_unwind(move || {
vec.insert_many(0, BadIter { hint: 1, count: 0 });
});
assert!(result.is_err());
}
#[test]
fn panic_early_in_middle() {
let mut vec: SmallVec<[PanicOnDoubleDrop; 0]> =
smallvec![PanicOnDoubleDrop::new(), PanicOnDoubleDrop::new(),];
let result = ::std::panic::catch_unwind(move || {
vec.insert_many(1, BadIter { hint: 4, count: 2 });
});
assert!(result.is_err());
}
#[test]
fn panic_early_at_end() {
let mut vec: SmallVec<[PanicOnDoubleDrop; 0]> =
smallvec![PanicOnDoubleDrop::new(), PanicOnDoubleDrop::new(),];
let result = ::std::panic::catch_unwind(move || {
vec.insert_many(2, BadIter { hint: 3, count: 1 });
});
assert!(result.is_err());
}
#[test]
fn panic_late_at_start() {
let mut vec: SmallVec<[PanicOnDoubleDrop; 0]> =
smallvec![PanicOnDoubleDrop::new(), PanicOnDoubleDrop::new(),];
let result = ::std::panic::catch_unwind(move || {
vec.insert_many(0, BadIter { hint: 3, count: 5 });
});
assert!(result.is_err());
}
#[test]
fn panic_late_at_end() {
let mut vec: SmallVec<[PanicOnDoubleDrop; 0]> =
smallvec![PanicOnDoubleDrop::new(), PanicOnDoubleDrop::new(),];
let result = ::std::panic::catch_unwind(move || {
vec.insert_many(2, BadIter { hint: 3, count: 5 });
});
assert!(result.is_err());
}
}
#[test]
#[should_panic]
fn test_invalid_grow() {
let mut v: SmallVec<[u8; 8]> = SmallVec::new();
v.extend(0..8);
v.grow(5);
}
#[test]
#[should_panic]
fn drain_overflow() {
let mut v: SmallVec<[u8; 8]> = smallvec![0];
v.drain(..=std::usize::MAX);
}
#[test]
fn test_insert_from_slice() {
let mut v: SmallVec<[u8; 8]> = SmallVec::new();
for x in 0..4 {
v.push(x);
}
assert_eq!(v.len(), 4);
v.insert_from_slice(1, &[5, 6]);
assert_eq!(
&v.iter().map(|v| *v).collect::<Vec<_>>(),
&[0, 5, 6, 1, 2, 3]
);
}
#[test]
fn test_extend_from_slice() {
let mut v: SmallVec<[u8; 8]> = SmallVec::new();
for x in 0..4 {
v.push(x);
}
assert_eq!(v.len(), 4);
v.extend_from_slice(&[5, 6]);
assert_eq!(
&v.iter().map(|v| *v).collect::<Vec<_>>(),
&[0, 1, 2, 3, 5, 6]
);
}
#[test]
#[should_panic]
fn test_drop_panic_smallvec() {
// This test should only panic once, and not double panic,
// which would mean a double drop
struct DropPanic;
impl Drop for DropPanic {
fn drop(&mut self) {
panic!("drop");
}
}
let mut v = SmallVec::<[_; 1]>::new();
v.push(DropPanic);
}
#[test]
fn test_eq() {
let mut a: SmallVec<[u32; 2]> = SmallVec::new();
let mut b: SmallVec<[u32; 2]> = SmallVec::new();
let mut c: SmallVec<[u32; 2]> = SmallVec::new();
// a = [1, 2]
a.push(1);
a.push(2);
// b = [1, 2]
b.push(1);
b.push(2);
// c = [3, 4]
c.push(3);
c.push(4);
assert!(a == b);
assert!(a != c);
}
#[test]
fn test_ord() {
let mut a: SmallVec<[u32; 2]> = SmallVec::new();
let mut b: SmallVec<[u32; 2]> = SmallVec::new();
let mut c: SmallVec<[u32; 2]> = SmallVec::new();
// a = [1]
a.push(1);
// b = [1, 1]
b.push(1);
b.push(1);
// c = [1, 2]
c.push(1);
c.push(2);
assert!(a < b);
assert!(b > a);
assert!(b < c);
assert!(c > b);
}
#[test]
fn test_hash() {
use std::collections::hash_map::DefaultHasher;
use std::hash::Hash;
{
let mut a: SmallVec<[u32; 2]> = SmallVec::new();
let b = [1, 2];
a.extend(b.iter().cloned());
let mut hasher = DefaultHasher::new();
assert_eq!(a.hash(&mut hasher), b.hash(&mut hasher));
}
{
let mut a: SmallVec<[u32; 2]> = SmallVec::new();
let b = [1, 2, 11, 12];
a.extend(b.iter().cloned());
let mut hasher = DefaultHasher::new();
assert_eq!(a.hash(&mut hasher), b.hash(&mut hasher));
}
}
#[test]
fn test_as_ref() {
let mut a: SmallVec<[u32; 2]> = SmallVec::new();
a.push(1);
assert_eq!(a.as_ref(), [1]);
a.push(2);
assert_eq!(a.as_ref(), [1, 2]);
a.push(3);
assert_eq!(a.as_ref(), [1, 2, 3]);
}
#[test]
fn test_as_mut() {
let mut a: SmallVec<[u32; 2]> = SmallVec::new();
a.push(1);
assert_eq!(a.as_mut(), [1]);
a.push(2);
assert_eq!(a.as_mut(), [1, 2]);
a.push(3);
assert_eq!(a.as_mut(), [1, 2, 3]);
a.as_mut()[1] = 4;
assert_eq!(a.as_mut(), [1, 4, 3]);
}
#[test]
fn test_borrow() {
use std::borrow::Borrow;
let mut a: SmallVec<[u32; 2]> = SmallVec::new();
a.push(1);
assert_eq!(a.borrow(), [1]);
a.push(2);
assert_eq!(a.borrow(), [1, 2]);
a.push(3);
assert_eq!(a.borrow(), [1, 2, 3]);
}
#[test]
fn test_borrow_mut() {
use std::borrow::BorrowMut;
let mut a: SmallVec<[u32; 2]> = SmallVec::new();
a.push(1);
assert_eq!(a.borrow_mut(), [1]);
a.push(2);
assert_eq!(a.borrow_mut(), [1, 2]);
a.push(3);
assert_eq!(a.borrow_mut(), [1, 2, 3]);
BorrowMut::<[u32]>::borrow_mut(&mut a)[1] = 4;
assert_eq!(a.borrow_mut(), [1, 4, 3]);
}
#[test]
fn test_from() {
assert_eq!(&SmallVec::<[u32; 2]>::from(&[1][..])[..], [1]);
assert_eq!(&SmallVec::<[u32; 2]>::from(&[1, 2, 3][..])[..], [1, 2, 3]);
let vec = vec![];
let small_vec: SmallVec<[u8; 3]> = SmallVec::from(vec);
assert_eq!(&*small_vec, &[]);
drop(small_vec);
let vec = vec![1, 2, 3, 4, 5];
let small_vec: SmallVec<[u8; 3]> = SmallVec::from(vec);
assert_eq!(&*small_vec, &[1, 2, 3, 4, 5]);
drop(small_vec);
let vec = vec![1, 2, 3, 4, 5];
let small_vec: SmallVec<[u8; 1]> = SmallVec::from(vec);
assert_eq!(&*small_vec, &[1, 2, 3, 4, 5]);
drop(small_vec);
let array = [1];
let small_vec: SmallVec<[u8; 1]> = SmallVec::from(array);
assert_eq!(&*small_vec, &[1]);
drop(small_vec);
let array = [99; 128];
let small_vec: SmallVec<[u8; 128]> = SmallVec::from(array);
assert_eq!(&*small_vec, vec![99u8; 128].as_slice());
drop(small_vec);
}
#[test]
fn test_from_slice() {
assert_eq!(&SmallVec::<[u32; 2]>::from_slice(&[1][..])[..], [1]);
assert_eq!(
&SmallVec::<[u32; 2]>::from_slice(&[1, 2, 3][..])[..],
[1, 2, 3]
);
}
#[test]
fn test_exact_size_iterator() {
let mut vec = SmallVec::<[u32; 2]>::from(&[1, 2, 3][..]);
assert_eq!(vec.clone().into_iter().len(), 3);
assert_eq!(vec.drain(..2).len(), 2);
assert_eq!(vec.into_iter().len(), 1);
}
#[test]
fn test_into_iter_as_slice() {
let vec = SmallVec::<[u32; 2]>::from(&[1, 2, 3][..]);
let mut iter = vec.clone().into_iter();
assert_eq!(iter.as_slice(), &[1, 2, 3]);
assert_eq!(iter.as_mut_slice(), &[1, 2, 3]);
iter.next();
assert_eq!(iter.as_slice(), &[2, 3]);
assert_eq!(iter.as_mut_slice(), &[2, 3]);
iter.next_back();
assert_eq!(iter.as_slice(), &[2]);
assert_eq!(iter.as_mut_slice(), &[2]);
}
#[test]
fn test_into_iter_clone() {
// Test that the cloned iterator yields identical elements and that it owns its own copy
// (i.e. no use after move errors).
let mut iter = SmallVec::<[u8; 2]>::from_iter(0..3).into_iter();
let mut clone_iter = iter.clone();
while let Some(x) = iter.next() {
assert_eq!(x, clone_iter.next().unwrap());
}
assert_eq!(clone_iter.next(), None);
}
#[test]
fn test_into_iter_clone_partially_consumed_iterator() {
// Test that the cloned iterator only contains the remaining elements of the original iterator.
let mut iter = SmallVec::<[u8; 2]>::from_iter(0..3).into_iter().skip(1);
let mut clone_iter = iter.clone();
while let Some(x) = iter.next() {
assert_eq!(x, clone_iter.next().unwrap());
}
assert_eq!(clone_iter.next(), None);
}
#[test]
fn test_into_iter_clone_empty_smallvec() {
let mut iter = SmallVec::<[u8; 2]>::new().into_iter();
let mut clone_iter = iter.clone();
assert_eq!(iter.next(), None);
assert_eq!(clone_iter.next(), None);
}
#[test]
fn shrink_to_fit_unspill() {
let mut vec = SmallVec::<[u8; 2]>::from_iter(0..3);
vec.pop();
assert!(vec.spilled());
vec.shrink_to_fit();
assert!(!vec.spilled(), "shrink_to_fit will un-spill if possible");
}
#[test]
fn test_into_vec() {
let vec = SmallVec::<[u8; 2]>::from_iter(0..2);
assert_eq!(vec.into_vec(), vec![0, 1]);
let vec = SmallVec::<[u8; 2]>::from_iter(0..3);
assert_eq!(vec.into_vec(), vec![0, 1, 2]);
}
#[test]
fn test_into_inner() {
let vec = SmallVec::<[u8; 2]>::from_iter(0..2);
assert_eq!(vec.into_inner(), Ok([0, 1]));
let vec = SmallVec::<[u8; 2]>::from_iter(0..1);
assert_eq!(vec.clone().into_inner(), Err(vec));
let vec = SmallVec::<[u8; 2]>::from_iter(0..3);
assert_eq!(vec.clone().into_inner(), Err(vec));
}
#[test]
fn test_from_vec() {
let vec = vec![];
let small_vec: SmallVec<[u8; 3]> = SmallVec::from_vec(vec);
assert_eq!(&*small_vec, &[]);
drop(small_vec);
let vec = vec![];
let small_vec: SmallVec<[u8; 1]> = SmallVec::from_vec(vec);
assert_eq!(&*small_vec, &[]);
drop(small_vec);
let vec = vec![1];
let small_vec: SmallVec<[u8; 3]> = SmallVec::from_vec(vec);
assert_eq!(&*small_vec, &[1]);
drop(small_vec);
let vec = vec![1, 2, 3];
let small_vec: SmallVec<[u8; 3]> = SmallVec::from_vec(vec);
assert_eq!(&*small_vec, &[1, 2, 3]);
drop(small_vec);
let vec = vec![1, 2, 3, 4, 5];
let small_vec: SmallVec<[u8; 3]> = SmallVec::from_vec(vec);
assert_eq!(&*small_vec, &[1, 2, 3, 4, 5]);
drop(small_vec);
let vec = vec![1, 2, 3, 4, 5];
let small_vec: SmallVec<[u8; 1]> = SmallVec::from_vec(vec);
assert_eq!(&*small_vec, &[1, 2, 3, 4, 5]);
drop(small_vec);
}
#[test]
fn test_retain() {
// Test inline data storate
let mut sv: SmallVec<[i32; 5]> = SmallVec::from_slice(&[1, 2, 3, 3, 4]);
sv.retain(|&mut i| i != 3);
assert_eq!(sv.pop(), Some(4));
assert_eq!(sv.pop(), Some(2));
assert_eq!(sv.pop(), Some(1));
assert_eq!(sv.pop(), None);
// Test spilled data storage
let mut sv: SmallVec<[i32; 3]> = SmallVec::from_slice(&[1, 2, 3, 3, 4]);
sv.retain(|&mut i| i != 3);
assert_eq!(sv.pop(), Some(4));
assert_eq!(sv.pop(), Some(2));
assert_eq!(sv.pop(), Some(1));
assert_eq!(sv.pop(), None);
// Test that drop implementations are called for inline.
let one = Rc::new(1);
let mut sv: SmallVec<[Rc<i32>; 3]> = SmallVec::new();
sv.push(Rc::clone(&one));
assert_eq!(Rc::strong_count(&one), 2);
sv.retain(|_| false);
assert_eq!(Rc::strong_count(&one), 1);
// Test that drop implementations are called for spilled data.
let mut sv: SmallVec<[Rc<i32>; 1]> = SmallVec::new();
sv.push(Rc::clone(&one));
sv.push(Rc::new(2));
assert_eq!(Rc::strong_count(&one), 2);
sv.retain(|_| false);
assert_eq!(Rc::strong_count(&one), 1);
}
#[test]
fn test_dedup() {
let mut dupes: SmallVec<[i32; 5]> = SmallVec::from_slice(&[1, 1, 2, 3, 3]);
dupes.dedup();
assert_eq!(&*dupes, &[1, 2, 3]);
let mut empty: SmallVec<[i32; 5]> = SmallVec::new();
empty.dedup();
assert!(empty.is_empty());
let mut all_ones: SmallVec<[i32; 5]> = SmallVec::from_slice(&[1, 1, 1, 1, 1]);
all_ones.dedup();
assert_eq!(all_ones.len(), 1);
let mut no_dupes: SmallVec<[i32; 5]> = SmallVec::from_slice(&[1, 2, 3, 4, 5]);
no_dupes.dedup();
assert_eq!(no_dupes.len(), 5);
}
#[test]
fn test_resize() {
let mut v: SmallVec<[i32; 8]> = SmallVec::new();
v.push(1);
v.resize(5, 0);
assert_eq!(v[..], [1, 0, 0, 0, 0][..]);
v.resize(2, -1);
assert_eq!(v[..], [1, 0][..]);
}
#[cfg(feature = "write")]
#[test]
fn test_write() {
use std::io::Write;
let data = [1, 2, 3, 4, 5];
let mut small_vec: SmallVec<[u8; 2]> = SmallVec::new();
let len = small_vec.write(&data[..]).unwrap();
assert_eq!(len, 5);
assert_eq!(small_vec.as_ref(), data.as_ref());
let mut small_vec: SmallVec<[u8; 2]> = SmallVec::new();
small_vec.write_all(&data[..]).unwrap();
assert_eq!(small_vec.as_ref(), data.as_ref());
}
#[cfg(feature = "serde")]
#[test]
fn test_serde() {
use bincode::{config, deserialize};
let mut small_vec: SmallVec<[i32; 2]> = SmallVec::new();
small_vec.push(1);
let encoded = config().limit(100).serialize(&small_vec).unwrap();
let decoded: SmallVec<[i32; 2]> = deserialize(&encoded).unwrap();
assert_eq!(small_vec, decoded);
small_vec.push(2);
// Spill the vec
small_vec.push(3);
small_vec.push(4);
// Check again after spilling.
let encoded = config().limit(100).serialize(&small_vec).unwrap();
let decoded: SmallVec<[i32; 2]> = deserialize(&encoded).unwrap();
assert_eq!(small_vec, decoded);
}
#[test]
fn grow_to_shrink() {
let mut v: SmallVec<[u8; 2]> = SmallVec::new();
v.push(1);
v.push(2);
v.push(3);
assert!(v.spilled());
v.clear();
// Shrink to inline.
v.grow(2);
assert!(!v.spilled());
assert_eq!(v.capacity(), 2);
assert_eq!(v.len(), 0);
v.push(4);
assert_eq!(v[..], [4]);
}
#[test]
fn resumable_extend() {
let s = "a b c";
// This iterator yields: (Some('a'), None, Some('b'), None, Some('c')), None
let it = s
.chars()
.scan(0, |_, ch| if ch.is_whitespace() { None } else { Some(ch) });
let mut v: SmallVec<[char; 4]> = SmallVec::new();
v.extend(it);
assert_eq!(v[..], ['a']);
}
// #139
#[test]
fn uninhabited() {
enum Void {}
let _sv = SmallVec::<[Void; 8]>::new();
}
#[test]
fn grow_spilled_same_size() {
let mut v: SmallVec<[u8; 2]> = SmallVec::new();
v.push(0);
v.push(1);
v.push(2);
assert!(v.spilled());
assert_eq!(v.capacity(), 4);
// grow with the same capacity
v.grow(4);
assert_eq!(v.capacity(), 4);
assert_eq!(v[..], [0, 1, 2]);
}
#[cfg(feature = "const_generics")]
#[test]
fn const_generics() {
let _v = SmallVec::<[i32; 987]>::default();
}
#[cfg(feature = "const_new")]
#[test]
fn const_new() {
let v = const_new_inner();
assert_eq!(v.capacity(), 4);
assert_eq!(v.len(), 0);
let v = const_new_inline_sized();
assert_eq!(v.capacity(), 4);
assert_eq!(v.len(), 4);
assert_eq!(v[0], 1);
let v = const_new_inline_args();
assert_eq!(v.capacity(), 2);
assert_eq!(v.len(), 2);
assert_eq!(v[0], 1);
assert_eq!(v[1], 4);
let v = const_new_with_len();
assert_eq!(v.capacity(), 4);
assert_eq!(v.len(), 3);
assert_eq!(v[0], 2);
assert_eq!(v[1], 5);
assert_eq!(v[2], 7);
}
#[cfg(feature = "const_new")]
const fn const_new_inner() -> SmallVec<[i32; 4]> {
SmallVec::<[i32; 4]>::new_const()
}
#[cfg(feature = "const_new")]
const fn const_new_inline_sized() -> SmallVec<[i32; 4]> {
crate::smallvec_inline![1; 4]
}
#[cfg(feature = "const_new")]
const fn const_new_inline_args() -> SmallVec<[i32; 2]> {
crate::smallvec_inline![1, 4]
}
#[cfg(feature = "const_new")]
const fn const_new_with_len() -> SmallVec<[i32; 4]> {
unsafe {
SmallVec::<[i32; 4]>::from_const_with_len_unchecked([2, 5, 7, 0], 3)
}
}
#[test]
fn empty_macro() {
let _v: SmallVec<[u8; 1]> = smallvec![];
}
#[test]
fn zero_size_items() {
SmallVec::<[(); 0]>::new().push(());
}
#[test]
fn test_insert_many_overflow() {
let mut v: SmallVec<[u8; 1]> = SmallVec::new();
v.push(123);
// Prepare an iterator with small lower bound
let iter = (0u8..5).filter(|n| n % 2 == 0);
assert_eq!(iter.size_hint().0, 0);
v.insert_many(0, iter);
assert_eq!(&*v, &[0, 2, 4, 123]);
}
#[test]
fn test_clone_from() {
let mut a: SmallVec<[u8; 2]> = SmallVec::new();
a.push(1);
a.push(2);
a.push(3);
let mut b: SmallVec<[u8; 2]> = SmallVec::new();
b.push(10);
let mut c: SmallVec<[u8; 2]> = SmallVec::new();
c.push(20);
c.push(21);
c.push(22);
a.clone_from(&b);
assert_eq!(&*a, &[10]);
b.clone_from(&c);
assert_eq!(&*b, &[20, 21, 22]);
}
#[test]
fn test_size() {
use core::mem::size_of;
assert_eq!(24, size_of::<SmallVec<[u8; 8]>>());
}
#[cfg(feature = "drain_filter")]
#[test]
fn drain_filter() {
let mut a: SmallVec<[u8; 2]> = smallvec![1u8, 2, 3, 4, 5, 6, 7, 8];
let b: SmallVec<[u8; 2]> = a.drain_filter(|x| *x % 3 == 0).collect();
assert_eq!(a, SmallVec::<[u8; 2]>::from_slice(&[1u8, 2, 4, 5, 7, 8]));
assert_eq!(b, SmallVec::<[u8; 2]>::from_slice(&[3u8, 6]));
}
#[cfg(feature = "drain_keep_rest")]
#[test]
fn drain_keep_rest() {
let mut a: SmallVec<[i32; 3]> = smallvec![1i32, 2, 3, 4, 5, 6, 7, 8];
let mut df = a.drain_filter(|x| *x % 2 == 0);
assert_eq!(df.next().unwrap(), 2);
assert_eq!(df.next().unwrap(), 4);
df.keep_rest();
assert_eq!(a, SmallVec::<[i32; 3]>::from_slice(&[1i32, 3, 5, 6, 7, 8]));
}