implement IntoIterator for Receiver

Author: rapha

src/libstd/sync/mpsc/mod.rs

@@ -277,6 +277,7 @@ pub use self::select::{Select, Handle};
 use self::select::StartResult;
 use self::select::StartResult::*;
 use self::blocking::SignalToken;
+use core::iter::IntoIterator;
 
 mod blocking;
 mod oneshot;
@@ -306,6 +307,10 @@ pub struct Iter<'a, T: 'a> {
     rx: &'a Receiver<T>
 }
 
+pub struct IntoIter<T> {
+    rx: Receiver<T>
+}
+
 /// The sending-half of Rust's asynchronous channel type. This half can only be
 /// owned by one task, but it can be cloned to send to other tasks.
 #[stable(feature = "rust1", since = "1.0.0")]
@@ -899,6 +904,20 @@ impl<'a, T> Iterator for Iter<'a, T> {
     fn next(&mut self) -> Option<T> { self.rx.recv().ok() }
 }
 
+impl<T> Iterator for IntoIter<T> {
+    type Item = T;
+    fn next(&mut self) -> Option<T> { self.rx.recv().ok() }
+}
+
+impl <T> IntoIterator for Receiver<T> {
+    type Item = T;
+    type IntoIter = IntoIter<T>;
+
+    fn into_iter(self) -> IntoIter<T> {
+        IntoIter { rx: self }
+    }
+}
+
 #[unsafe_destructor]
 #[stable(feature = "rust1", since = "1.0.0")]
 impl<T> Drop for Receiver<T> {
@@ -1507,6 +1526,22 @@ mod test {
         assert_eq!(count_rx.recv().unwrap(), 4);
     }
 
+    #[test]
+    fn test_recv_into_iter() {
+        use core::iter::IntoIterator;
+
+        let mut iter = {
+          let (tx, rx) = channel::<i32>();
+          tx.send(1).unwrap();
+          tx.send(2).unwrap();
+
+          rx.into_iter()
+        };
+        assert_eq!(iter.next().unwrap(), 1);
+        assert_eq!(iter.next().unwrap(), 2);
+        assert_eq!(iter.next().is_none(), true);
+    }
+
     #[test]
     fn try_recv_states() {
         let (tx1, rx1) = channel::<i32>();