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// Regression test for #61320
// This is the same issue as #61311, just a larger test case.
// check-pass
pub struct AndThen<A, B, F>
where
A: Future,
B: IntoFuture,
{
state: (A, B::Future, F),
}
pub struct FutureResult<T, E> {
inner: Option<Result<T, E>>,
}
impl<T, E> Future for FutureResult<T, E> {
type Item = T;
type Error = E;
fn poll(&mut self) -> Poll<T, E> {
unimplemented!()
}
}
pub type Poll<T, E> = Result<T, E>;
impl<A, B, F> Future for AndThen<A, B, F>
where
A: Future,
B: IntoFuture<Error = A::Error>,
F: FnOnce(A::Item) -> B,
{
type Item = B::Item;
type Error = B::Error;
fn poll(&mut self) -> Poll<B::Item, B::Error> {
unimplemented!()
}
}
pub trait Future {
type Item;
type Error;
fn poll(&mut self) -> Poll<Self::Item, Self::Error>;
fn and_then<F, B>(self, f: F) -> AndThen<Self, B, F>
where
F: FnOnce(Self::Item) -> B,
B: IntoFuture<Error = Self::Error>,
Self: Sized,
{
unimplemented!()
}
}
pub trait IntoFuture {
/// The future that this type can be converted into.
type Future: Future<Item = Self::Item, Error = Self::Error>;
/// The item that the future may resolve with.
type Item;
/// The error that the future may resolve with.
type Error;
/// Consumes this object and produces a future.
fn into_future(self) -> Self::Future;
}
impl<F: Future> IntoFuture for F {
type Future = F;
type Item = F::Item;
type Error = F::Error;
fn into_future(self) -> F {
self
}
}
impl<F: ?Sized + Future> Future for ::std::boxed::Box<F> {
type Item = F::Item;
type Error = F::Error;
fn poll(&mut self) -> Poll<Self::Item, Self::Error> {
(**self).poll()
}
}
impl<T, E> IntoFuture for Result<T, E> {
type Future = FutureResult<T, E>;
type Item = T;
type Error = E;
fn into_future(self) -> FutureResult<T, E> {
unimplemented!()
}
}
struct Request<T>(T);
trait RequestContext {}
impl<T> RequestContext for T {}
struct NoContext;
impl AsRef<NoContext> for NoContext {
fn as_ref(&self) -> &Self {
&NoContext
}
}
type BoxedError = Box<dyn std::error::Error + Send + Sync>;
type DefaultFuture<T, E> = Box<dyn Future<Item = T, Error = E> + Send>;
trait Guard: Sized {
type Result: IntoFuture<Item = Self, Error = BoxedError>;
fn from_request(request: &Request<()>) -> Self::Result;
}
trait FromRequest: Sized {
type Context;
type Future: Future<Item = Self, Error = BoxedError> + Send;
fn from_request(request: Request<()>) -> Self::Future;
}
struct MyGuard;
impl Guard for MyGuard {
type Result = Result<Self, BoxedError>;
fn from_request(_request: &Request<()>) -> Self::Result {
Ok(MyGuard)
}
}
struct Generic<I> {
_inner: I,
}
impl<I> FromRequest for Generic<I>
where
MyGuard: Guard,
<MyGuard as Guard>::Result: IntoFuture<Item = MyGuard, Error = BoxedError>,
<<MyGuard as Guard>::Result as IntoFuture>::Future: Send,
I: FromRequest<Context = NoContext>,
{
type Future = DefaultFuture<Self, BoxedError>;
type Context = NoContext;
fn from_request(headers: Request<()>) -> DefaultFuture<Self, BoxedError> {
let _future = <MyGuard as Guard>::from_request(&headers)
.into_future()
.and_then(move |_| {
<I as FromRequest>::from_request(headers)
.into_future()
.and_then(move |fld_inner| Ok(Generic { _inner: fld_inner }).into_future())
});
panic!();
}
}
fn main() {}
|
