src/test/ui/dropck/dropck_traits.rs

   1 // run-pass
   2 //! Regression test for #34426, regarding HRTB in drop impls
   3
   4 // All of this Drop impls should compile.
   5
   6 pub trait Lifetime<'a> {}
   7 impl<'a> Lifetime<'a> for i32 {}
   8
   9 #[allow(dead_code)]
  10 struct Foo<L>
  11 where
  12     for<'a> L: Lifetime<'a>,
  13 {
  14     l: L,
  15 }
  16
  17 impl<L> Drop for Foo<L>
  18 where
  19     for<'a> L: Lifetime<'a>,
  20 {
  21     fn drop(&mut self) {}
  22 }
  23
  24 #[allow(dead_code)]
  25 struct Foo2<L>
  26 where
  27     for<'a> L: Lifetime<'a>,
  28 {
  29     l: L,
  30 }
  31
  32 impl<T: for<'a> Lifetime<'a>> Drop for Foo2<T>
  33 where
  34     for<'x> T: Lifetime<'x>,
  35 {
  36     fn drop(&mut self) {}
  37 }
  38
  39 pub trait Lifetime2<'a, 'b> {}
  40 impl<'a, 'b> Lifetime2<'a, 'b> for i32 {}
  41
  42 #[allow(dead_code)]
  43 struct Bar<L>
  44 where
  45     for<'a, 'b> L: Lifetime2<'a, 'b>,
  46 {
  47     l: L,
  48 }
  49
  50 impl<L> Drop for Bar<L>
  51 where
  52     for<'a, 'b> L: Lifetime2<'a, 'b>,
  53 {
  54     fn drop(&mut self) {}
  55 }
  56
  57 #[allow(dead_code)]
  58 struct FnHolder<T: for<'a> Fn(&'a T, dyn for<'b> Lifetime2<'a, 'b>) -> u8>(T);
  59
  60 impl<T: for<'a> Fn(&'a T, dyn for<'b> Lifetime2<'a, 'b>) -> u8> Drop for FnHolder<T> {
  61     fn drop(&mut self) {}
  62 }
  63
  64 fn main() {
  65     let _foo = Foo { l: 0 };
  66
  67     let _bar = Bar { l: 0 };
  68 }