src/test/ui/builtin-superkinds/builtin-superkinds-capabilities-transitive.rs

   1 // run-pass
   2 // Tests "transitivity" of super-builtin-kinds on traits. Here, if
   3 // we have a Foo, we know we have a Bar, and if we have a Bar, we
   4 // know we have a Send. So if we have a Foo we should know we have
   5 // a Send. Basically this just makes sure rustc is using
   6 // each_bound_trait_and_supertraits in type_contents correctly.
   7
   8
   9 use std::sync::mpsc::{channel, Sender};
  10
  11 trait Bar : Send { }
  12 trait Foo : Bar { }
  13
  14 impl <T: Send> Foo for T { }
  15 impl <T: Send> Bar for T { }
  16
  17 fn foo<T: Foo + 'static>(val: T, chan: Sender<T>) {
  18     chan.send(val).unwrap();
  19 }
  20
  21 pub fn main() {
  22     let (tx, rx) = channel();
  23     foo(31337, tx);
  24     assert_eq!(rx.recv().unwrap(), 31337);
  25 }