Add tests for Iterator::copied()

Author: KamilaBorowska

src/libcore/tests/iter.rs

@@ -1232,6 +1232,23 @@ fn test_rev() {
             vec![16, 14, 12, 10, 8, 6]);
 }
 
+#[test]
+fn test_copied() {
+    let xs = [2, 4, 6, 8];
+
+    let mut it = xs.iter().copied();
+    assert_eq!(it.len(), 4);
+    assert_eq!(it.next(), Some(2));
+    assert_eq!(it.len(), 3);
+    assert_eq!(it.next(), Some(4));
+    assert_eq!(it.len(), 2);
+    assert_eq!(it.next_back(), Some(8));
+    assert_eq!(it.len(), 1);
+    assert_eq!(it.next_back(), Some(6));
+    assert_eq!(it.len(), 0);
+    assert_eq!(it.next_back(), None);
+}
+
 #[test]
 fn test_cloned() {
     let xs = [2, 4, 6, 8];

src/libcore/tests/lib.rs

@@ -20,6 +20,7 @@
 #![feature(flt2dec)]
 #![feature(fmt_internals)]
 #![feature(hashmap_internals)]
+#![feature(iter_copied)]
 #![feature(iter_unfold)]
 #![feature(pattern)]
 #![feature(range_is_empty)]