Hint for E0790 does not result in valid code (missing path to implementation)

[jruderman]

Code

mod base {
    pub trait T {
        fn f();
    }

    pub struct S;

    impl T for S {
        fn f() {}
    }
}

pub fn foo() {
    base::T::f();
}

fn main() { }

Current output

error[E0790]: cannot call associated function on trait without specifying the corresponding `impl` type
  --> awex.rs:14:5
   |
3  |         fn f();
   |         ------- `T::f` defined here
...
14 |     base::T::f();
   |     ^^^^^^^^^^ cannot call associated function of trait
   |
help: use the fully-qualified path to the only available implementation
   |
14 |     <S as base::T>::f();
   |     +++++        +

Desired output

help: use the fully-qualified path to the only available implementation
   |
14 |     <base::S as base::T>::f();
   |     +++++++++++        +

Rationale and extra context

Since base::S has not been imported, the hint code should use base::S rather than S

Other cases

No response

Anything else?

I noticed this in tests/ui/traits/static-method-generic-inference.rs. Reduced to isolate the issue.

[estebank]

When applying the suggestion you do get the following error:

error[E0412]: cannot find type `S` in this scope
  --> src/main.rs:14:6
   |
14 |     <S as base::T>::f();
   |      ^ not found in this scope
   |
help: consider importing this struct
   |
1  + use crate::base::S;
   |

which lowers the urgency in fixing this. I'm realizing that we can choose to use with_forced_trimmed_paths! or with_no_trimmed_paths! based on whether the DefId is accessible from the current scope, given that we are already in resolve by the time we emit this error. This goes for both the self ty and the trait.