1 files changed, 142 insertions, 0 deletions
diff --git a/vendor/futures-util-0.3.14/src/future/try_join_all.rs b/vendor/futures-util-0.3.14/src/future/try_join_all.rs
new file mode 100644
index 00000000..371f753f
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+++ b/vendor/futures-util-0.3.14/src/future/try_join_all.rs
@@ -0,0 +1,142 @@
+//! Definition of the `TryJoinAll` combinator, waiting for all of a list of
+//! futures to finish with either success or error.
+
+use core::fmt;
+use core::future::Future;
+use core::iter::FromIterator;
+use core::mem;
+use core::pin::Pin;
+use core::task::{Context, Poll};
+use alloc::boxed::Box;
+use alloc::vec::Vec;
+
+use super::{assert_future, TryFuture, TryMaybeDone};
+
+fn iter_pin_mut<T>(slice: Pin<&mut [T]>) -> impl Iterator<Item = Pin<&mut T>> {
+    // Safety: `std` _could_ make this unsound if it were to decide Pin's
+    // invariants aren't required to transmit through slices. Otherwise this has
+    // the same safety as a normal field pin projection.
+    unsafe { slice.get_unchecked_mut() }
+        .iter_mut()
+        .map(|t| unsafe { Pin::new_unchecked(t) })
+}
+
+enum FinalState<E = ()> {
+    Pending,
+    AllDone,
+    Error(E)
+}
+
+/// Future for the [`try_join_all`] function.
+#[must_use = "futures do nothing unless you `.await` or poll them"]
+pub struct TryJoinAll<F>
+where
+    F: TryFuture,
+{
+    elems: Pin<Box<[TryMaybeDone<F>]>>,
+}
+
+impl<F> fmt::Debug for TryJoinAll<F>
+where
+    F: TryFuture + fmt::Debug,
+    F::Ok: fmt::Debug,
+    F::Error: fmt::Debug,
+{
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_struct("TryJoinAll")
+            .field("elems", &self.elems)
+            .finish()
+    }
+}
+
+/// Creates a future which represents either a collection of the results of the
+/// futures given or an error.
+///
+/// The returned future will drive execution for all of its underlying futures,
+/// collecting the results into a destination `Vec<T>` in the same order as they
+/// were provided.
+///
+/// If any future returns an error then all other futures will be canceled and
+/// an error will be returned immediately. If all futures complete successfully,
+/// however, then the returned future will succeed with a `Vec` of all the
+/// successful results.
+///
+/// This function is only available when the `std` or `alloc` feature of this
+/// library is activated, and it is activated by default.
+///
+/// # Examples
+///
+/// ```
+/// # futures::executor::block_on(async {
+/// use futures::future::{self, try_join_all};
+///
+/// let futures = vec![
+///     future::ok::<u32, u32>(1),
+///     future::ok::<u32, u32>(2),
+///     future::ok::<u32, u32>(3),
+/// ];
+///
+/// assert_eq!(try_join_all(futures).await, Ok(vec![1, 2, 3]));
+///
+/// let futures = vec![
+///     future::ok::<u32, u32>(1),
+///     future::err::<u32, u32>(2),
+///     future::ok::<u32, u32>(3),
+/// ];
+///
+/// assert_eq!(try_join_all(futures).await, Err(2));
+/// # });
+/// ```
+pub fn try_join_all<I>(i: I) -> TryJoinAll<I::Item>
+where
+    I: IntoIterator,
+    I::Item: TryFuture,
+{
+    let elems: Box<[_]> = i.into_iter().map(TryMaybeDone::Future).collect();
+    assert_future::<Result<Vec<<I::Item as TryFuture>::Ok>, <I::Item as TryFuture>::Error>, _>(TryJoinAll {
+        elems: elems.into(),
+    })
+}
+
+impl<F> Future for TryJoinAll<F>
+where
+    F: TryFuture,
+{
+    type Output = Result<Vec<F::Ok>, F::Error>;
+
+    fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
+        let mut state = FinalState::AllDone;
+
+        for elem in iter_pin_mut(self.elems.as_mut()) {
+            match elem.try_poll(cx) {
+                Poll::Pending => state = FinalState::Pending,
+                Poll::Ready(Ok(())) => {},
+                Poll::Ready(Err(e)) => {
+                    state = FinalState::Error(e);
+                    break;
+                }
+            }
+        }
+
+        match state {
+            FinalState::Pending => Poll::Pending,
+            FinalState::AllDone => {
+                let mut elems = mem::replace(&mut self.elems, Box::pin([]));
+                let results = iter_pin_mut(elems.as_mut())
+                    .map(|e| e.take_output().unwrap())
+                    .collect();
+                Poll::Ready(Ok(results))
+            },
+            FinalState::Error(e) => {
+                let _ = mem::replace(&mut self.elems, Box::pin([]));
+                Poll::Ready(Err(e))
+            },
+        }
+    }
+}
+
+impl<F: TryFuture> FromIterator<F> for TryJoinAll<F> {
+    fn from_iter<T: IntoIterator<Item = F>>(iter: T) -> Self {
+        try_join_all(iter)
+    }
+}