error: methods with the following characteristics: (`to_*` and `self` type is not `Copy`) usually take `self` by reference
  --> $DIR/wrong_self_conventions_mut.rs:14:24
   |
LL |         pub fn to_many(&mut self) -> Option<&mut [T]> {
   |                        ^^^^^^^^^
   |
   = help: consider choosing a less ambiguous name
   = note: `-D clippy::wrong-self-convention` implied by `-D warnings`

error: methods with the following characteristics: (`to_*` and `*_mut`) usually take `self` by mutable reference
  --> $DIR/wrong_self_conventions_mut.rs:23:28
   |
LL |         pub fn to_many_mut(&self) -> Option<&[T]> {
   |                            ^^^^^
   |
   = help: consider choosing a less ambiguous name

error: aborting due to 2 previous errors