Merge pull request rust-lang#84 from jeandudey/return-a

Return A type parameter on ReadToEnd

futures-io/src/read_to_end.rs

@@ -8,8 +8,15 @@ use futures::{Poll, Future};
 ///
 /// Created by the `read_to_end` function.
 pub struct ReadToEnd<A> {
-    a: A,
-    buf: Vec<u8>,
+    state: State<A>,
+}
+
+enum State<A> {
+    Reading {
+        a: A,
+        buf: Vec<u8>,
+    },
+    Empty,
 }
 
 /// Creates a future which will read all the bytes associated with the I/O
@@ -23,22 +30,33 @@ pub fn read_to_end<A>(a: A, buf: Vec<u8>) -> ReadToEnd<A>
     where A: Read,
 {
     ReadToEnd {
-        a: a,
-        buf: buf,
+        state: State::Reading {
+            a: a,
+            buf: buf,
+        }
     }
 }
 
 impl<A> Future for ReadToEnd<A>
     where A: Read,
 {
-    type Item = Vec<u8>;
+    type Item = (A, Vec<u8>);
     type Error = io::Error;
 
-    fn poll(&mut self) -> Poll<Vec<u8>, io::Error> {
-        // If we get `Ok`, then we know the stream hit EOF and we're done. If we
-        // hit "would block" then all the read data so far is in our buffer, and
-        // otherwise we propagate errors.
-        try_nb!(self.a.read_to_end(&mut self.buf));
-        Poll::Ok(mem::replace(&mut self.buf, Vec::new()))
+    fn poll(&mut self) -> Poll<(A, Vec<u8>), io::Error> {
+        match self.state {
+            State::Reading { ref mut a, ref mut buf } => {
+                // If we get `Ok`, then we know the stream hit EOF and we're done. If we
+                // hit "would block" then all the read data so far is in our buffer, and
+                // otherwise we propagate errors
+                try_nb!(a.read_to_end(buf));
+            },
+            State::Empty => panic!("poll ReadToEnd after it's done"),
+        }
+
+        match mem::replace(&mut self.state, State::Empty) {
+            State::Reading { a, buf } => Poll::Ok((a, buf)),
+            State::Empty => unreachable!(),
+        }
     }
 }

futures-mio/tests/chain.rs

@@ -43,7 +43,7 @@ fn chain_clients() {
         read_to_end(a.chain(b).chain(c), Vec::new())
     });
 
-    let data = t!(l.run(copied));
+    let (_, data) = t!(l.run(copied));
     t.join().unwrap();
 
     assert_eq!(data, b"foo bar baz");

futures-mio/tests/limit.rs

@@ -37,7 +37,7 @@ fn limit() {
         read_to_end(a.take(4), Vec::new())
     });
 
-    let data = t!(l.run(copied));
+    let (_, data) = t!(l.run(copied));
     t.join().unwrap();
 
     assert_eq!(data, b"foo ");

futures-tls/tests/google.rs

@@ -82,7 +82,7 @@ fn fetch_google() {
         read_to_end(socket, Vec::new())
     });
 
-    let data = t!(l.run(data));
+    let (_, data) = t!(l.run(data));
     assert!(data.starts_with(b"HTTP/1.0 200 OK"));
     assert!(data.ends_with(b"</html>"));
 }

futures-tls/tests/smoke.rs

@@ -456,7 +456,7 @@ fn client_to_server() {
     });
 
     // Finally, run everything!
-    let (amt, data) = t!(l.run(sent.join(received)));
+    let (amt, (_, data)) = t!(l.run(sent.join(received)));
     assert_eq!(amt, AMT);
     assert!(data == vec![9; amt as usize]);
 }
@@ -488,7 +488,7 @@ fn server_to_client() {
     });
 
     // Finally, run everything!
-    let (amt, data) = t!(l.run(sent.join(received)));
+    let (amt, (_, data)) = t!(l.run(sent.join(received)));
     assert_eq!(amt, AMT);
     assert!(data == vec![9; amt as usize]);
 }
@@ -538,7 +538,7 @@ fn one_byte_at_a_time() {
         read_to_end(socket, Vec::new())
     });
 
-    let (amt, data) = t!(l.run(sent.join(received)));
+    let (amt, (_, data)) = t!(l.run(sent.join(received)));
     assert_eq!(amt, AMT);
     assert!(data == vec![9; amt as usize]);
 }