38 lines
794 B
Rust
38 lines
794 B
Rust
// edition: 2021
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// check-pass
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// This test verifies that we do not create a query cycle when typechecking has several inference
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// variables that point to the same coroutine interior type.
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use std::future::Future;
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use std::pin::Pin;
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use std::task::{Context, Poll};
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type ChannelTask = Pin<Box<dyn Future<Output = ()> + Send>>;
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pub fn register_message_type() -> ChannelTask {
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Box::pin(async move {
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let f = |__cx: &mut Context<'_>| Poll::<()>::Pending;
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PollFn { f }.await
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})
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}
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struct PollFn<F> {
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f: F,
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}
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impl<F> Unpin for PollFn<F> {}
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impl<T, F> Future for PollFn<F>
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where
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F: FnMut(&mut Context<'_>) -> Poll<T>,
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{
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type Output = T;
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fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<T> {
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(&mut self.f)(cx)
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}
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}
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fn main() {}
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