vendor/itertools/tests/tuples.rs

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