rust-clippy/tests/ui/unnecessary_fallible_conversions_unfixable.rs

43 lines
1.5 KiB
Rust

//@aux-build:proc_macros.rs
//@no-rustfix
#![warn(clippy::unnecessary_fallible_conversions)]
extern crate proc_macros;
struct Foo;
impl TryFrom<i32> for Foo {
type Error = ();
fn try_from(_: i32) -> Result<Self, Self::Error> {
Ok(Foo)
}
}
impl From<i64> for Foo {
fn from(_: i64) -> Self {
Foo
}
}
fn main() {
// `Foo` only implements `TryFrom<i32>` and not `From<i32>`, so don't lint
let _: Result<Foo, _> = 0i32.try_into();
let _: Result<Foo, _> = i32::try_into(0i32);
let _: Result<Foo, _> = Foo::try_from(0i32);
// ... it does impl From<i64> however
let _: Result<Foo, _> = 0i64.try_into();
//~^ ERROR: use of a fallible conversion when an infallible one could be used
let _: Result<Foo, _> = i64::try_into(0i64);
//~^ ERROR: use of a fallible conversion when an infallible one could be used
let _: Result<Foo, _> = Foo::try_from(0i64);
//~^ ERROR: use of a fallible conversion when an infallible one could be used
let _: Result<i64, _> = 0i32.try_into();
//~^ ERROR: use of a fallible conversion when an infallible one could be used
let _: Result<i64, _> = i32::try_into(0i32);
//~^ ERROR: use of a fallible conversion when an infallible one could be used
let _: Result<i64, _> = <_>::try_from(0i32);
//~^ ERROR: use of a fallible conversion when an infallible one could be used
// From a macro
let _: Result<i64, _> = proc_macros::external!(0i32).try_into();
}