vendor/itertools/tests/tuples.rs

   1 extern crate itertools;
   2
   3 use itertools::Itertools;
   4
   5 #[test]
   6 fn tuples() {
   7     let v = [1, 2, 3, 4, 5];
   8     let mut iter = v.iter().cloned().tuples();
   9     assert_eq!(Some((1,)), iter.next());
  10     assert_eq!(Some((2,)), iter.next());
  11     assert_eq!(Some((3,)), iter.next());
  12     assert_eq!(Some((4,)), iter.next());
  13     assert_eq!(Some((5,)), iter.next());
  14     assert_eq!(None, iter.next());
  15     assert_eq!(None, iter.into_buffer().next());
  16
  17     let mut iter = v.iter().cloned().tuples();
  18     assert_eq!(Some((1, 2)), iter.next());
  19     assert_eq!(Some((3, 4)), iter.next());
  20     assert_eq!(None, iter.next());
  21     itertools::assert_equal(vec![5], iter.into_buffer());
  22
  23     let mut iter = v.iter().cloned().tuples();
  24     assert_eq!(Some((1, 2, 3)), iter.next());
  25     assert_eq!(None, iter.next());
  26     itertools::assert_equal(vec![4, 5], iter.into_buffer());
  27
  28     let mut iter = v.iter().cloned().tuples();
  29     assert_eq!(Some((1, 2, 3, 4)), iter.next());
  30     assert_eq!(None, iter.next());
  31     itertools::assert_equal(vec![5], iter.into_buffer());
  32 }
  33
  34 #[test]
  35 fn tuple_windows() {
  36     let v = [1, 2, 3, 4, 5];
  37
  38     let mut iter = v.iter().cloned().tuple_windows();
  39     assert_eq!(Some((1,)), iter.next());
  40     assert_eq!(Some((2,)), iter.next());
  41     assert_eq!(Some((3,)), iter.next());
  42
  43     let mut iter = v.iter().cloned().tuple_windows();
  44     assert_eq!(Some((1, 2)), iter.next());
  45     assert_eq!(Some((2, 3)), iter.next());
  46     assert_eq!(Some((3, 4)), iter.next());
  47     assert_eq!(Some((4, 5)), iter.next());
  48     assert_eq!(None, iter.next());
  49
  50     let mut iter = v.iter().cloned().tuple_windows();
  51     assert_eq!(Some((1, 2, 3)), iter.next());
  52     assert_eq!(Some((2, 3, 4)), iter.next());
  53     assert_eq!(Some((3, 4, 5)), iter.next());
  54     assert_eq!(None, iter.next());
  55
  56     let mut iter = v.iter().cloned().tuple_windows();
  57     assert_eq!(Some((1, 2, 3, 4)), iter.next());
  58     assert_eq!(Some((2, 3, 4, 5)), iter.next());
  59     assert_eq!(None, iter.next());
  60
  61     let v = [1, 2, 3];
  62     let mut iter = v.iter().cloned().tuple_windows::<(_, _, _, _)>();
  63     assert_eq!(None, iter.next());
  64 }
  65
  66 #[test]
  67 fn next_tuple() {
  68     let v = [1, 2, 3, 4, 5];
  69     let mut iter = v.iter();
  70     assert_eq!(iter.next_tuple().map(|(&x, &y)| (x, y)), Some((1, 2)));
  71     assert_eq!(iter.next_tuple().map(|(&x, &y)| (x, y)), Some((3, 4)));
  72     assert_eq!(iter.next_tuple::<(_, _)>(), None);
  73 }
  74
  75 #[test]
  76 fn collect_tuple() {
  77     let v = [1, 2];
  78     let iter = v.iter().cloned();
  79     assert_eq!(iter.collect_tuple(), Some((1, 2)));
  80
  81     let v = [1];
  82     let iter = v.iter().cloned();
  83     assert_eq!(iter.collect_tuple::<(_, _)>(), None);
  84
  85     let v = [1, 2, 3];
  86     let iter = v.iter().cloned();
  87     assert_eq!(iter.collect_tuple::<(_, _)>(), None);
  88 }