When a trait isn't implemented, but another similar impl is found, point at it
```
error[E0277]: the trait bound `u32: Trait` is not satisfied
--> $DIR/trait_objects_fail.rs:26:9
|
LL | foo(&10_u32);
| ^^^^^^^ the trait `Trait` is not implemented for `u32`
|
help: the trait `Trait<12>` is not implemented for `u32`
but trait `Trait<2>` is implemented for it
--> $DIR/trait_objects_fail.rs:7:1
|
LL | impl Trait<2> for u32 {}
| ^^^^^^^^^^^^^^^^^^^^^
= note: required for the cast from `&u32` to `&dyn Trait`
```
Pointing at the `impl` definition that *could* apply given a different self type is *particularly* useful when it has a blanket self type, as it might not be obvious and is not trivially greppable:
```
error[E0277]: the trait bound `RawImpl<_>: Raw<_>` is not satisfied
--> $DIR/issue-62742.rs:4:5
|
LL | WrongImpl::foo(0i32);
| ^^^^^^^^^ unsatisfied trait bound
|
help: the trait `Raw<_>` is not implemented for `RawImpl<_>`
but trait `Raw<[_]>` is implemented for it
--> $DIR/issue-62742.rs:29:1
|
LL | impl<T> Raw<[T]> for RawImpl<T> {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
note: required by a bound in `SafeImpl`
--> $DIR/issue-62742.rs:33:35
|
LL | pub struct SafeImpl<T: ?Sized, A: Raw<T>>(PhantomData<(A, T)>);
| ^^^^^^ required by this bound in `SafeImpl`
```
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