tests/ui/impl-trait/impl-generic-mismatch.rs

   1 use std::fmt::Debug;
   2
   3 trait Foo {
   4     fn foo(&self, _: &impl Debug);
   5 }
   6
   7 impl Foo for () {
   8     fn foo<U: Debug>(&self, _: &U) { }
   9     //~^ Error method `foo` has incompatible signature for trait
  10 }
  11
  12 trait Bar {
  13     fn bar<U: Debug>(&self, _: &U);
  14 }
  15
  16 impl Bar for () {
  17     fn bar(&self, _: &impl Debug) { }
  18     //~^ Error method `bar` has incompatible signature for trait
  19 }
  20
  21 trait Baz {
  22     fn baz<U: Debug, T: Debug>(&self, _: &U, _: &T);
  23 }
  24
  25 impl Baz for () {
  26     fn baz<T: Debug>(&self, _: &impl Debug, _: &T) { }
  27     //~^ Error method `baz` has incompatible signature for trait
  28 }
  29
  30 // With non-local trait (#49841):
  31
  32 use std::hash::{Hash, Hasher};
  33
  34 struct X;
  35
  36 impl Hash for X {
  37     fn hash(&self, hasher: &mut impl Hasher) {}
  38     //~^ Error method `hash` has incompatible signature for trait
  39 }
  40
  41 fn main() {}