1 files changed, 66 insertions, 0 deletions
diff --git a/library/core/tests/iter/traits/accum.rs b/library/core/tests/iter/traits/accum.rs
new file mode 100644
index 000000000..f3eeb31fe
--- /dev/null
+++ b/library/core/tests/iter/traits/accum.rs
@@ -0,0 +1,66 @@
+use core::iter::*;
+
+#[test]
+fn test_iterator_sum() {
+    let v: &[i32] = &[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
+    assert_eq!(v[..4].iter().cloned().sum::<i32>(), 6);
+    assert_eq!(v.iter().cloned().sum::<i32>(), 55);
+    assert_eq!(v[..0].iter().cloned().sum::<i32>(), 0);
+}
+
+#[test]
+fn test_iterator_sum_result() {
+    let v: &[Result<i32, ()>] = &[Ok(1), Ok(2), Ok(3), Ok(4)];
+    assert_eq!(v.iter().cloned().sum::<Result<i32, _>>(), Ok(10));
+    let v: &[Result<i32, ()>] = &[Ok(1), Err(()), Ok(3), Ok(4)];
+    assert_eq!(v.iter().cloned().sum::<Result<i32, _>>(), Err(()));
+
+    #[derive(PartialEq, Debug)]
+    struct S(Result<i32, ()>);
+
+    impl Sum<Result<i32, ()>> for S {
+        fn sum<I: Iterator<Item = Result<i32, ()>>>(mut iter: I) -> Self {
+            // takes the sum by repeatedly calling `next` on `iter`,
+            // thus testing that repeated calls to `ResultShunt::try_fold`
+            // produce the expected results
+            Self(iter.by_ref().sum())
+        }
+    }
+
+    let v: &[Result<i32, ()>] = &[Ok(1), Ok(2), Ok(3), Ok(4)];
+    assert_eq!(v.iter().cloned().sum::<S>(), S(Ok(10)));
+    let v: &[Result<i32, ()>] = &[Ok(1), Err(()), Ok(3), Ok(4)];
+    assert_eq!(v.iter().cloned().sum::<S>(), S(Err(())));
+}
+
+#[test]
+fn test_iterator_sum_option() {
+    let v: &[Option<i32>] = &[Some(1), Some(2), Some(3), Some(4)];
+    assert_eq!(v.iter().cloned().sum::<Option<i32>>(), Some(10));
+    let v: &[Option<i32>] = &[Some(1), None, Some(3), Some(4)];
+    assert_eq!(v.iter().cloned().sum::<Option<i32>>(), None);
+}
+
+#[test]
+fn test_iterator_product() {
+    let v: &[i32] = &[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
+    assert_eq!(v[..4].iter().cloned().product::<i32>(), 0);
+    assert_eq!(v[1..5].iter().cloned().product::<i32>(), 24);
+    assert_eq!(v[..0].iter().cloned().product::<i32>(), 1);
+}
+
+#[test]
+fn test_iterator_product_result() {
+    let v: &[Result<i32, ()>] = &[Ok(1), Ok(2), Ok(3), Ok(4)];
+    assert_eq!(v.iter().cloned().product::<Result<i32, _>>(), Ok(24));
+    let v: &[Result<i32, ()>] = &[Ok(1), Err(()), Ok(3), Ok(4)];
+    assert_eq!(v.iter().cloned().product::<Result<i32, _>>(), Err(()));
+}
+
+#[test]
+fn test_iterator_product_option() {
+    let v: &[Option<i32>] = &[Some(1), Some(2), Some(3), Some(4)];
+    assert_eq!(v.iter().cloned().product::<Option<i32>>(), Some(24));
+    let v: &[Option<i32>] = &[Some(1), None, Some(3), Some(4)];
+    assert_eq!(v.iter().cloned().product::<Option<i32>>(), None);
+}