error: the following explicit lifetimes could be elided: 'a
  --> $DIR/issue_4266.rs:4:1
   |
LL | async fn sink1<'a>(_: &'a str) {} // lint
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = note: `-D clippy::needless-lifetimes` implied by `-D warnings`

error: the following explicit lifetimes could be elided: 'a
  --> $DIR/issue_4266.rs:8:1
   |
LL | async fn one_to_one<'a>(s: &'a str) -> &'a str {
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

error: methods called `new` usually take no `self`
  --> $DIR/issue_4266.rs:28:22
   |
LL |     pub async fn new(&mut self) -> Self {
   |                      ^^^^^^^^^
   |
   = help: consider choosing a less ambiguous name
   = note: `-D clippy::wrong-self-convention` implied by `-D warnings`

error: aborting due to 3 previous errors