use itertools::Itertools; use itertools::{put_back, put_back_n}; #[test] fn peeking_take_while_peekable() { let mut r = (0..10).peekable(); r.peeking_take_while(|x| *x <= 3).count(); assert_eq!(r.next(), Some(4)); } #[test] fn peeking_take_while_put_back() { let mut r = put_back(0..10); r.peeking_take_while(|x| *x <= 3).count(); assert_eq!(r.next(), Some(4)); r.peeking_take_while(|_| true).count(); assert_eq!(r.next(), None); } #[test] fn peeking_take_while_put_back_n() { let mut r = put_back_n(6..10); for elt in (0..6).rev() { r.put_back(elt); } r.peeking_take_while(|x| *x <= 3).count(); assert_eq!(r.next(), Some(4)); r.peeking_take_while(|_| true).count(); assert_eq!(r.next(), None); } #[test] fn peeking_take_while_slice_iter() { let v = [1, 2, 3, 4, 5, 6]; let mut r = v.iter(); r.peeking_take_while(|x| **x <= 3).count(); assert_eq!(r.next(), Some(&4)); r.peeking_take_while(|_| true).count(); assert_eq!(r.next(), None); } #[test] fn peeking_take_while_slice_iter_rev() { let v = [1, 2, 3, 4, 5, 6]; let mut r = v.iter().rev(); r.peeking_take_while(|x| **x >= 3).count(); assert_eq!(r.next(), Some(&2)); r.peeking_take_while(|_| true).count(); assert_eq!(r.next(), None); }