rust_2021_prelude_collisions suggestions cause compile error with generics #88442
Description
Given the following code:
#![allow(unused)]
#![warn(rust_2021_prelude_collisions)]
trait AnnotatableTryInto {
fn try_into<T>(self) -> Result<T, Self::Error>
where Self: std::convert::TryInto<T> {
std::convert::TryInto::try_into(self)
}
}
impl<T> AnnotatableTryInto for T where T: From<u8> {}
fn main() -> Result<(), &'static str> {
let x: u64 = 1;
x.try_into::<usize>().or(Err("foo"))?.checked_sub(1);
x.try_into::<usize>().or(Err("foo"))?;
Ok(())
}The rust_2021_prelude_collisions lint provides two suggestions, both of which fail with different errors. The first:
AnnotatableTryInto::try_into(x).or(Err("foo"))?.checked_sub(1);fails with "type annotations needed" because the generics in the path ::<usize> are lost.
The second:
AnnotatableTryInto::try_into(x).or(Err("foo"))?;fails with "the trait bound (): From<u64> is not satisfied".
Ideally I think the suggestions should be:
AnnotatableTryInto::try_into::<usize>(x).or(Err("foo"))?.checked_sub(1);
AnnotatableTryInto::try_into::<usize>(x).or(Err("foo"))?;Found in the 2021 crate run migrating https://crater-reports.s3.amazonaws.com/pr-87190-3/try%23a7a572ce3edd6d476191fbfe92c9c1986e009b34/reg/kamadak-exif-0.5.4/log.txt
rustc 1.56.0-nightly (ac50a5335 2021-08-27)
binary: rustc
commit-hash: ac50a53359328a5d7f2f558833e63d59d372e4f7
commit-date: 2021-08-27
host: x86_64-apple-darwin
release: 1.56.0-nightly
LLVM version: 13.0.0