1 files changed, 86 insertions, 0 deletions
diff --git a/third_party/rust/itertools/tests/tuples.rs b/third_party/rust/itertools/tests/tuples.rs
new file mode 100644
index 0000000000..9fc8b3cc78
--- /dev/null
+++ b/third_party/rust/itertools/tests/tuples.rs
@@ -0,0 +1,86 @@
+use itertools::Itertools;
+
+#[test]
+fn tuples() {
+    let v = [1, 2, 3, 4, 5];
+    let mut iter = v.iter().cloned().tuples();
+    assert_eq!(Some((1,)), iter.next());
+    assert_eq!(Some((2,)), iter.next());
+    assert_eq!(Some((3,)), iter.next());
+    assert_eq!(Some((4,)), iter.next());
+    assert_eq!(Some((5,)), iter.next());
+    assert_eq!(None, iter.next());
+    assert_eq!(None, iter.into_buffer().next());
+
+    let mut iter = v.iter().cloned().tuples();
+    assert_eq!(Some((1, 2)), iter.next());
+    assert_eq!(Some((3, 4)), iter.next());
+    assert_eq!(None, iter.next());
+    itertools::assert_equal(vec![5], iter.into_buffer());
+
+    let mut iter = v.iter().cloned().tuples();
+    assert_eq!(Some((1, 2, 3)), iter.next());
+    assert_eq!(None, iter.next());
+    itertools::assert_equal(vec![4, 5], iter.into_buffer());
+
+    let mut iter = v.iter().cloned().tuples();
+    assert_eq!(Some((1, 2, 3, 4)), iter.next());
+    assert_eq!(None, iter.next());
+    itertools::assert_equal(vec![5], iter.into_buffer());
+}
+
+#[test]
+fn tuple_windows() {
+    let v = [1, 2, 3, 4, 5];
+
+    let mut iter = v.iter().cloned().tuple_windows();
+    assert_eq!(Some((1,)), iter.next());
+    assert_eq!(Some((2,)), iter.next());
+    assert_eq!(Some((3,)), iter.next());
+
+    let mut iter = v.iter().cloned().tuple_windows();
+    assert_eq!(Some((1, 2)), iter.next());
+    assert_eq!(Some((2, 3)), iter.next());
+    assert_eq!(Some((3, 4)), iter.next());
+    assert_eq!(Some((4, 5)), iter.next());
+    assert_eq!(None, iter.next());
+
+    let mut iter = v.iter().cloned().tuple_windows();
+    assert_eq!(Some((1, 2, 3)), iter.next());
+    assert_eq!(Some((2, 3, 4)), iter.next());
+    assert_eq!(Some((3, 4, 5)), iter.next());
+    assert_eq!(None, iter.next());
+
+    let mut iter = v.iter().cloned().tuple_windows();
+    assert_eq!(Some((1, 2, 3, 4)), iter.next());
+    assert_eq!(Some((2, 3, 4, 5)), iter.next());
+    assert_eq!(None, iter.next());
+
+    let v = [1, 2, 3];
+    let mut iter = v.iter().cloned().tuple_windows::<(_, _, _, _)>();
+    assert_eq!(None, iter.next());
+}
+
+#[test]
+fn next_tuple() {
+    let v = [1, 2, 3, 4, 5];
+    let mut iter = v.iter();
+    assert_eq!(iter.next_tuple().map(|(&x, &y)| (x, y)), Some((1, 2)));
+    assert_eq!(iter.next_tuple().map(|(&x, &y)| (x, y)), Some((3, 4)));
+    assert_eq!(iter.next_tuple::<(_, _)>(), None);
+}
+
+#[test]
+fn collect_tuple() {
+    let v = [1, 2];
+    let iter = v.iter().cloned();
+    assert_eq!(iter.collect_tuple(), Some((1, 2)));
+
+    let v = [1];
+    let iter = v.iter().cloned();
+    assert_eq!(iter.collect_tuple::<(_, _)>(), None);
+
+    let v = [1, 2, 3];
+    let iter = v.iter().cloned();
+    assert_eq!(iter.collect_tuple::<(_, _)>(), None);
+}