1 files changed, 45 insertions, 0 deletions
diff --git a/tokio/src/io/util/flush.rs b/tokio/src/io/util/flush.rs
new file mode 100644
index 00000000..61253ab5
--- /dev/null
+++ b/tokio/src/io/util/flush.rs
@@ -0,0 +1,45 @@
+use crate::io::AsyncWrite;
+
+use std::future::Future;
+use std::io;
+use std::pin::Pin;
+use std::task::{Context, Poll};
+
+/// A future used to fully flush an I/O object.
+///
+/// Created by the [`AsyncWriteExt::flush`] function.
+#[derive(Debug)]
+pub struct Flush<'a, A: ?Sized> {
+    a: &'a mut A,
+}
+
+/// Creates a future which will entirely flush an I/O object.
+pub(super) fn flush<A>(a: &mut A) -> Flush<'_, A>
+where
+    A: AsyncWrite + Unpin + ?Sized,
+{
+    Flush { a }
+}
+
+impl<A> Future for Flush<'_, A>
+where
+    A: AsyncWrite + Unpin + ?Sized,
+{
+    type Output = io::Result<()>;
+
+    fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
+        let me = &mut *self;
+        Pin::new(&mut *me.a).poll_flush(cx)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn assert_unpin() {
+        use std::marker::PhantomPinned;
+        crate::is_unpin::<Flush<'_, PhantomPinned>>();
+    }
+}