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// run-rustfix
// edition:2018
// check-pass
#![warn(rust_2021_prelude_collisions)]
trait TryIntoU32 {
fn try_into(self) -> Result<u32, ()>;
}
impl TryIntoU32 for u8 {
fn try_into(self) -> Result<u32, ()> {
Ok(self as u32)
}
}
// needed for autoref test
impl TryIntoU32 for &f32 {
fn try_into(self) -> Result<u32, ()> {
Ok(*self as u32)
}
}
trait TryFromU8: Sized {
fn try_from(x: u8) -> Result<Self, ()>;
}
impl TryFromU8 for u32 {
fn try_from(x: u8) -> Result<Self, ()> {
Ok(x as u32)
}
}
impl TryIntoU32 for *const u16 {
fn try_into(self) -> Result<u32, ()> {
Ok(unsafe { *self } as u32)
}
}
trait FromByteIterator {
fn from_iter<T>(iter: T) -> Self
where
T: Iterator<Item = u8>;
}
impl FromByteIterator for Vec<u8> {
fn from_iter<T>(iter: T) -> Self
where
T: Iterator<Item = u8>,
{
iter.collect()
}
}
fn main() {
// test dot-call that will break in 2021 edition
let _: u32 = 3u8.try_into().unwrap();
//~^ WARNING trait method `try_into` will become ambiguous in Rust 2021
//~^^ WARNING this is accepted in the current edition
// test associated function call that will break in 2021 edition
let _ = u32::try_from(3u8).unwrap();
//~^ WARNING trait-associated function `try_from` will become ambiguous in Rust 2021
//~^^ WARNING this is accepted in the current edition
// test reverse turbofish too
let _ = <Vec<u8>>::from_iter(vec![1u8, 2, 3, 4, 5, 6].into_iter());
//~^ WARNING trait-associated function `from_iter` will become ambiguous in Rust 2021
//~^^ WARNING this is accepted in the current edition
// negative testing lint (this line should *not* emit a warning)
let _: u32 = TryFromU8::try_from(3u8).unwrap();
// test type omission
let _: u32 = <_>::try_from(3u8).unwrap();
//~^ WARNING trait-associated function `try_from` will become ambiguous in Rust 2021
//~^^ WARNING this is accepted in the current edition
// test autoderef
let _: u32 = (&3u8).try_into().unwrap();
//~^ WARNING trait method `try_into` will become ambiguous in Rust 2021
//~^^ WARNING this is accepted in the current edition
// test autoref
let _: u32 = 3.0.try_into().unwrap();
//~^ WARNING trait method `try_into` will become ambiguous in Rust 2021
//~^^ WARNING this is accepted in the current edition
let mut data = 3u16;
let mut_ptr = std::ptr::addr_of_mut!(data);
let _: u32 = mut_ptr.try_into().unwrap();
//~^ WARNING trait method `try_into` will become ambiguous in Rust 2021
//~^^ WARNING this is accepted in the current edition
type U32Alias = u32;
let _ = U32Alias::try_from(3u8).unwrap();
//~^ WARNING trait-associated function `try_from` will become ambiguous in Rust 2021
//~^^ WARNING this is accepted in the current edition
}
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