error: implementation of inherent method `to_string(&self) -> String` for type `A`
  --> $DIR/inherent_to_string.rs:20:5
   |
LL | /     fn to_string(&self) -> String {
LL | |         "A.to_string()".to_string()
LL | |     }
   | |_____^
   |
   = note: `-D clippy::inherent-to-string` implied by `-D warnings`
   = help: implement trait `Display` for type `A` instead

error: type `C` implements inherent method `to_string(&self) -> String` which shadows the implementation of `Display`
  --> $DIR/inherent_to_string.rs:44:5
   |
LL | /     fn to_string(&self) -> String {
LL | |         "C.to_string()".to_string()
LL | |     }
   | |_____^
   |
note: the lint level is defined here
  --> $DIR/inherent_to_string.rs:2:9
   |
LL | #![deny(clippy::inherent_to_string_shadow_display)]
   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   = help: remove the inherent method from type `C`

error: aborting due to 2 previous errors