error: expected `;`
 --> tests/ui/function-body.rs:9:42
  |
9 |     pub fn ref_cast(s: &String) -> &Self {}
  |                                          ^

error[E0308]: mismatched types
 --> tests/ui/function-body.rs:9:36
  |
9 |     pub fn ref_cast(s: &String) -> &Self {}
  |            --------                ^^^^^ expected `&Thing`, found `()`
  |            |
  |            implicitly returns `()` as its body has no tail or `return` expression