// Test case where the method we want is an inherent method on a // dyn Trait. In that case, the fix is to insert `*` on the receiver. // // check-pass // run-rustfix // edition:2018 #![warn(future_prelude_collision)] trait TryIntoU32 { fn try_into(&self) -> Result; } impl TryIntoU32 for u8 { // note: &self fn try_into(&self) -> Result { Ok(22) } } mod inner { use super::get_dyn_trait; // note: this does nothing, but is copying from ffishim's problem of // having a struct of the same name as the trait in-scope, while *also* // implementing the trait for that struct but **without** importing the // trait itself into scope struct TryIntoU32; impl super::TryIntoU32 for TryIntoU32 { fn try_into(&self) -> Result { Ok(0) } } // this is where the gross part happens. since `get_dyn_trait` returns // a Box, it can still call the method for `dyn Trait` without // `Trait` being in-scope. it might even be possible to make the trait itself // entirely unreference-able from the callsite? pub fn test() -> u32 { (&*get_dyn_trait()).try_into().unwrap() //~^ WARNING trait method `try_into` will become ambiguous //~| WARNING this was previously accepted } } fn get_dyn_trait() -> Box { Box::new(3u8) as Box } fn main() { dbg!(inner::test()); }