Structs

Collect all the awaited expressions within the input expression.
Collect the spans that we see the generic param param_did
Collect all the returned expressions within the input expression. Used to point at the return spans when we want to suggest some change to them.

Enums

Traits

Functions

Type parameter needs more bounds. The trivial case is T where T: Bound, but it can also be an impl Trait param that needs to be decomposed to a type param for cleaner code.