Use TryStreamExt::into_async_read in io tests

Author: taiki-e

futures-util/src/try_stream/into_async_read.rs

@@ -139,6 +139,8 @@ where
         mut self: Pin<&mut Self>,
         amount: usize,
     ) {
+         // https://github.com/rust-lang-nursery/futures-rs/pull/1556#discussion_r281644295
+        if amount == 0 { return }
         if let ReadState::Ready { chunk, chunk_start } = &mut self.state {
             *chunk_start += amount;
             debug_assert!(*chunk_start <= chunk.as_ref().len());

futures/tests/io_read_line.rs

@@ -1,5 +1,6 @@
 use futures::executor::block_on;
 use futures::future::Future;
+use futures::stream::{self, StreamExt, TryStreamExt};
 use futures::io::AsyncBufReadExt;
 use futures::task::Poll;
 use futures_test::io::AsyncReadTestExt;
@@ -42,7 +43,10 @@ fn maybe_pending() {
     assert_eq!(run(buf.read_line(&mut v)).unwrap(), 2);
     assert_eq!(v, "12");
 
-    let mut buf = b"12\n\n".interleave_pending();
+    let mut buf = stream::iter(vec![&b"12"[..], &b"\n\n"[..]])
+        .map(Ok)
+        .into_async_read()
+        .interleave_pending();
     let mut v = String::new();
     assert_eq!(run(buf.read_line(&mut v)).unwrap(), 3);
     assert_eq!(v, "12\n");

futures/tests/io_read_until.rs

@@ -1,5 +1,6 @@
 use futures::executor::block_on;
 use futures::future::Future;
+use futures::stream::{self, StreamExt, TryStreamExt};
 use futures::io::AsyncBufReadExt;
 use futures::task::Poll;
 use futures_test::io::AsyncReadTestExt;
@@ -42,7 +43,10 @@ fn maybe_pending() {
     assert_eq!(run(buf.read_until(b'3', &mut v)).unwrap(), 2);
     assert_eq!(v, b"12");
 
-    let mut buf = b"12333".interleave_pending();
+    let mut buf = stream::iter(vec![&b"12"[..], &b"33"[..], &b"3"[..]])
+        .map(Ok)
+        .into_async_read()
+        .interleave_pending();
     let mut v = Vec::new();
     assert_eq!(run(buf.read_until(b'3', &mut v)).unwrap(), 3);
     assert_eq!(v, b"123");