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#![allow(
clippy::map_unwrap_or,
clippy::needless_lifetimes,
clippy::uninlined_format_args
)]
use syn::punctuated::{Pair, Punctuated};
use syn::{parse_quote, GenericParam, Generics, Lifetime, LifetimeParam, Token};
#[macro_use]
mod macros;
macro_rules! check_exact_size_iterator {
($iter:expr) => {{
let iter = $iter;
let size_hint = iter.size_hint();
let len = iter.len();
let count = iter.count();
assert_eq!(len, count);
assert_eq!(size_hint, (count, Some(count)));
}};
}
#[test]
fn pairs() {
let mut p: Punctuated<_, Token![,]> = punctuated!(2, 3, 4);
check_exact_size_iterator!(p.pairs());
check_exact_size_iterator!(p.pairs_mut());
check_exact_size_iterator!(p.into_pairs());
let mut p: Punctuated<_, Token![,]> = punctuated!(2, 3, 4);
assert_eq!(p.pairs().next_back().map(Pair::into_value), Some(&4));
assert_eq!(
p.pairs_mut().next_back().map(Pair::into_value),
Some(&mut 4)
);
assert_eq!(p.into_pairs().next_back().map(Pair::into_value), Some(4));
}
#[test]
fn iter() {
let mut p: Punctuated<_, Token![,]> = punctuated!(2, 3, 4);
check_exact_size_iterator!(p.iter());
check_exact_size_iterator!(p.iter_mut());
check_exact_size_iterator!(p.into_iter());
let mut p: Punctuated<_, Token![,]> = punctuated!(2, 3, 4);
assert_eq!(p.iter().next_back(), Some(&4));
assert_eq!(p.iter_mut().next_back(), Some(&mut 4));
assert_eq!(p.into_iter().next_back(), Some(4));
}
#[test]
fn may_dangle() {
let p: Punctuated<_, Token![,]> = punctuated!(2, 3, 4);
for element in &p {
if *element == 2 {
drop(p);
break;
}
}
let mut p: Punctuated<_, Token![,]> = punctuated!(2, 3, 4);
for element in &mut p {
if *element == 2 {
drop(p);
break;
}
}
}
#[test]
fn no_opaque_drop() {
let mut generics = Generics::default();
let _ = generics
.lifetimes()
.next()
.map(|param| param.lifetime.clone())
.unwrap_or_else(|| {
let lifetime: Lifetime = parse_quote!('a);
generics.params.insert(
0,
GenericParam::Lifetime(LifetimeParam::new(lifetime.clone())),
);
lifetime
});
}