Description
Some rstest
users report an error on nightly-2022-11-22 (see la10736/rstest#169 ).
I narrowed down the regression to the following code:
Code
I tried this code:
struct It;
struct Data {
items: Vec<It>,
}
impl Data {
fn new() -> Self {
Self {
items: vec![It, It],
}
}
fn content(&self) -> impl Iterator<Item = &It> {
self.items.iter()
}
}
struct Container<'a> {
name: String,
resolver: Box<dyn Resolver + 'a>,
}
impl<'a> Container<'a> {
fn new<R: Resolver + 'a>(name: &str, resolver: R) -> Self {
Self {
name: name.to_owned(),
resolver: Box::new(resolver),
}
}
}
trait Resolver {}
impl<R: Resolver> Resolver for &R {}
impl Resolver for It {}
fn get<'a>(mut items: impl Iterator<Item = &'a It>) -> impl Resolver + 'a {
items.next().unwrap()
}
fn main() {
let data = Data::new();
let resolver = get(data.content());
let _ = ["a", "b"]
.iter()
.map(|&n| Container::new(n, &resolver))
.map(|c| c.name)
.collect::<Vec<_>>();
}
I expected to see this happen: It should compile
Instead, this happened: not compile
mdamico@miklap:~/dev_random/lifetime$ cargo build
Compiling lifetime v0.1.0 (/home/mdamico/dev_random/lifetime)
error: `get<'_, impl Iterator<Item = &It>>::{opaque#1}<'_>` does not live long enough
--> src/main.rs:49:19
|
49 | .map(|&n| Container::new(n, &resolver))
| ^^^^^^^^^^^^^^
error: `get<'_, impl Iterator<Item = &It>>::{opaque#1}<'_>` does not live long enough
--> src/main.rs:49:19
|
49 | .map(|&n| Container::new(n, &resolver))
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: could not compile `lifetime` due to 2 previous errors
Version it worked on
It most recently worked on: 1.65.0 stable, 1.66.0-beta.2 (0040709 2022-11-20), nightly-2022-11-21
Version with regression
rustc --version --verbose
:
mdamico@miklap:~/dev_random/lifetime$ rustc --version --verbose
rustc 1.67.0-nightly (b7bc90fea 2022-11-21)
binary: rustc
commit-hash: b7bc90fea3b441234a84b49fdafeb75815eebbab
commit-date: 2022-11-21
host: x86_64-unknown-linux-gnu
release: 1.67.0-nightly
LLVM version: 15.0.4
Backtrace
Backtrace
<backtrace>