From 64d98f8ee037282c35007b64c2649055c56af1db Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Wed, 17 Apr 2024 14:19:03 +0200 Subject: Merging upstream version 1.68.2+dfsg1. Signed-off-by: Daniel Baumann --- tests/ui/dyn-star/dyn-async-trait.rs | 36 ++++++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) create mode 100644 tests/ui/dyn-star/dyn-async-trait.rs (limited to 'tests/ui/dyn-star/dyn-async-trait.rs') diff --git a/tests/ui/dyn-star/dyn-async-trait.rs b/tests/ui/dyn-star/dyn-async-trait.rs new file mode 100644 index 000000000..9b27133b4 --- /dev/null +++ b/tests/ui/dyn-star/dyn-async-trait.rs @@ -0,0 +1,36 @@ +// check-pass +// edition: 2021 + +// This test case is meant to demonstrate how close we can get to async +// functions in dyn traits with the current level of dyn* support. + +#![feature(dyn_star)] +#![allow(incomplete_features)] + +use std::future::Future; + +trait DynAsyncCounter { + fn increment<'a>(&'a mut self) -> dyn* Future + 'a; +} + +struct MyCounter { + count: usize, +} + +impl DynAsyncCounter for MyCounter { + fn increment<'a>(&'a mut self) -> dyn* Future + 'a { + Box::pin(async { + self.count += 1; + self.count + }) + } +} + +async fn do_counter(counter: &mut dyn DynAsyncCounter) -> usize { + counter.increment().await +} + +fn main() { + let mut counter = MyCounter { count: 0 }; + let _ = do_counter(&mut counter); +} -- cgit v1.2.3