impl AsyncWrite for std::io::Cursor (#1730)

Based on the implementation from the futures crate.

1 files changed, 72 insertions, 0 deletions

diff --git a/tokio/src/io/async_write.rs b/tokio/src/io/async_write.rs
index dc8b852f..0489fb7c 100644
--- a/tokio/src/io/async_write.rs
+++ b/tokio/src/io/async_write.rs
@@ -209,3 +209,75 @@ impl AsyncWrite for Vec<u8> {
         Poll::Ready(Ok(()))
     }
 }
+
+impl AsyncWrite for io::Cursor<&mut [u8]> {
+    fn poll_write(
+        mut self: Pin<&mut Self>,
+        _: &mut Context<'_>,
+        buf: &[u8],
+    ) -> Poll<io::Result<usize>> {
+        Poll::Ready(io::Write::write(&mut *self, buf))
+    }
+
+    fn poll_flush(mut self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<io::Result<()>> {
+        Poll::Ready(io::Write::flush(&mut *self))
+    }
+
+    fn poll_shutdown(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<()>> {
+        self.poll_flush(cx)
+    }
+}
+
+impl AsyncWrite for io::Cursor<&mut Vec<u8>> {
+    fn poll_write(
+        mut self: Pin<&mut Self>,
+        _: &mut Context<'_>,
+        buf: &[u8],
+    ) -> Poll<io::Result<usize>> {
+        Poll::Ready(io::Write::write(&mut *self, buf))
+    }
+
+    fn poll_flush(mut self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<io::Result<()>> {
+        Poll::Ready(io::Write::flush(&mut *self))
+    }
+
+    fn poll_shutdown(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<()>> {
+        self.poll_flush(cx)
+    }
+}
+
+impl AsyncWrite for io::Cursor<Vec<u8>> {
+    fn poll_write(
+        mut self: Pin<&mut Self>,
+        _: &mut Context<'_>,
+        buf: &[u8],
+    ) -> Poll<io::Result<usize>> {
+        Poll::Ready(io::Write::write(&mut *self, buf))
+    }
+
+    fn poll_flush(mut self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<io::Result<()>> {
+        Poll::Ready(io::Write::flush(&mut *self))
+    }
+
+    fn poll_shutdown(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<()>> {
+        self.poll_flush(cx)
+    }
+}
+
+impl AsyncWrite for io::Cursor<Box<[u8]>> {
+    fn poll_write(
+        mut self: Pin<&mut Self>,
+        _: &mut Context<'_>,
+        buf: &[u8],
+    ) -> Poll<io::Result<usize>> {
+        Poll::Ready(io::Write::write(&mut *self, buf))
+    }
+
+    fn poll_flush(mut self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<io::Result<()>> {
+        Poll::Ready(io::Write::flush(&mut *self))
+    }
+
+    fn poll_shutdown(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<()>> {
+        self.poll_flush(cx)
+    }
+}