error[E0599]: no method named `foo` found for type `Bar` in the current scope
  --> $DIR/issue-21659-show-relevant-trait-impls-3.rs:20:8
   |
LL | struct Bar;
   | ----------- method `foo` not found for this
...
LL |     f1.foo(1usize);
   |        ^^^
   |
   = help: items from traits can only be used if the trait is implemented and in scope
   = note: the following trait defines an item `foo`, perhaps you need to implement it:
           candidate #1: `Foo`

error: aborting due to previous error

For more information about this error, try `rustc --explain E0599`.