--- /dev/null
+
+#[macro_use] extern crate itertools as it;
+extern crate permutohedron;
+
+use it::Itertools;
+use it::multizip;
+use it::multipeek;
+use it::free::rciter;
+use it::free::put_back_n;
+use it::FoldWhile;
+use it::cloned;
+
+#[test]
+fn product3() {
+ let prod = iproduct!(0..3, 0..2, 0..2);
+ assert_eq!(prod.size_hint(), (12, Some(12)));
+ let v = prod.collect_vec();
+ for i in 0..3 {
+ for j in 0..2 {
+ for k in 0..2 {
+ assert!((i, j, k) == v[(i * 2 * 2 + j * 2 + k) as usize]);
+ }
+ }
+ }
+ for (_, _, _, _) in iproduct!(0..3, 0..2, 0..2, 0..3) {
+ /* test compiles */
+ }
+}
+
+#[test]
+fn interleave_shortest() {
+ let v0: Vec<i32> = vec![0, 2, 4];
+ let v1: Vec<i32> = vec![1, 3, 5, 7];
+ let it = v0.into_iter().interleave_shortest(v1.into_iter());
+ assert_eq!(it.size_hint(), (6, Some(6)));
+ assert_eq!(it.collect_vec(), vec![0, 1, 2, 3, 4, 5]);
+
+ let v0: Vec<i32> = vec![0, 2, 4, 6, 8];
+ let v1: Vec<i32> = vec![1, 3, 5];
+ let it = v0.into_iter().interleave_shortest(v1.into_iter());
+ assert_eq!(it.size_hint(), (7, Some(7)));
+ assert_eq!(it.collect_vec(), vec![0, 1, 2, 3, 4, 5, 6]);
+
+ let i0 = ::std::iter::repeat(0);
+ let v1: Vec<_> = vec![1, 3, 5];
+ let it = i0.interleave_shortest(v1.into_iter());
+ assert_eq!(it.size_hint(), (7, Some(7)));
+
+ let v0: Vec<_> = vec![0, 2, 4];
+ let i1 = ::std::iter::repeat(1);
+ let it = v0.into_iter().interleave_shortest(i1);
+ assert_eq!(it.size_hint(), (6, Some(6)));
+}
+
+
+#[test]
+fn unique_by() {
+ let xs = ["aaa", "bbbbb", "aa", "ccc", "bbbb", "aaaaa", "cccc"];
+ let ys = ["aaa", "bbbbb", "ccc"];
+ it::assert_equal(ys.iter(), xs.iter().unique_by(|x| x[..2].to_string()));
+}
+
+#[test]
+fn unique() {
+ let xs = [0, 1, 2, 3, 2, 1, 3];
+ let ys = [0, 1, 2, 3];
+ it::assert_equal(ys.iter(), xs.iter().unique());
+ let xs = [0, 1];
+ let ys = [0, 1];
+ it::assert_equal(ys.iter(), xs.iter().unique());
+}
+
+#[test]
+fn intersperse() {
+ let xs = ["a", "", "b", "c"];
+ let v: Vec<&str> = xs.iter().map(|x| x.clone()).intersperse(", ").collect();
+ let text: String = v.concat();
+ assert_eq!(text, "a, , b, c".to_string());
+
+ let ys = [0, 1, 2, 3];
+ let mut it = ys[..0].iter().map(|x| *x).intersperse(1);
+ assert!(it.next() == None);
+}
+
+#[test]
+fn dedup() {
+ let xs = [0, 1, 1, 1, 2, 1, 3, 3];
+ let ys = [0, 1, 2, 1, 3];
+ it::assert_equal(ys.iter(), xs.iter().dedup());
+ let xs = [0, 0, 0, 0, 0];
+ let ys = [0];
+ it::assert_equal(ys.iter(), xs.iter().dedup());
+
+ let xs = [0, 1, 1, 1, 2, 1, 3, 3];
+ let ys = [0, 1, 2, 1, 3];
+ let mut xs_d = Vec::new();
+ xs.iter().dedup().fold((), |(), &elt| xs_d.push(elt));
+ assert_eq!(&xs_d, &ys);
+}
+
+#[test]
+fn dedup_by() {
+ let xs = [(0, 0), (0, 1), (1, 1), (2, 1), (0, 2), (3, 1), (0, 3), (1, 3)];
+ let ys = [(0, 0), (0, 1), (0, 2), (3, 1), (0, 3)];
+ it::assert_equal(ys.iter(), xs.iter().dedup_by(|x, y| x.1==y.1));
+ let xs = [(0, 1), (0, 2), (0, 3), (0, 4), (0, 5)];
+ let ys = [(0, 1)];
+ it::assert_equal(ys.iter(), xs.iter().dedup_by(|x, y| x.0==y.0));
+
+ let xs = [(0, 0), (0, 1), (1, 1), (2, 1), (0, 2), (3, 1), (0, 3), (1, 3)];
+ let ys = [(0, 0), (0, 1), (0, 2), (3, 1), (0, 3)];
+ let mut xs_d = Vec::new();
+ xs.iter().dedup_by(|x, y| x.1==y.1).fold((), |(), &elt| xs_d.push(elt));
+ assert_eq!(&xs_d, &ys);
+}
+
+#[test]
+fn all_equal() {
+ assert!("".chars().all_equal());
+ assert!("A".chars().all_equal());
+ assert!(!"AABBCCC".chars().all_equal());
+ assert!("AAAAAAA".chars().all_equal());
+ for (_key, mut sub) in &"AABBCCC".chars().group_by(|&x| x) {
+ assert!(sub.all_equal());
+ }
+}
+
+#[test]
+fn test_put_back_n() {
+ let xs = [0, 1, 1, 1, 2, 1, 3, 3];
+ let mut pb = put_back_n(xs.iter().cloned());
+ pb.next();
+ pb.next();
+ pb.put_back(1);
+ pb.put_back(0);
+ it::assert_equal(pb, xs.iter().cloned());
+}
+
+#[test]
+fn tee() {
+ let xs = [0, 1, 2, 3];
+ let (mut t1, mut t2) = xs.iter().cloned().tee();
+ assert_eq!(t1.next(), Some(0));
+ assert_eq!(t2.next(), Some(0));
+ assert_eq!(t1.next(), Some(1));
+ assert_eq!(t1.next(), Some(2));
+ assert_eq!(t1.next(), Some(3));
+ assert_eq!(t1.next(), None);
+ assert_eq!(t2.next(), Some(1));
+ assert_eq!(t2.next(), Some(2));
+ assert_eq!(t1.next(), None);
+ assert_eq!(t2.next(), Some(3));
+ assert_eq!(t2.next(), None);
+ assert_eq!(t1.next(), None);
+ assert_eq!(t2.next(), None);
+
+ let (t1, t2) = xs.iter().cloned().tee();
+ it::assert_equal(t1, xs.iter().cloned());
+ it::assert_equal(t2, xs.iter().cloned());
+
+ let (t1, t2) = xs.iter().cloned().tee();
+ it::assert_equal(t1.zip(t2), xs.iter().cloned().zip(xs.iter().cloned()));
+}
+
+
+#[test]
+fn test_rciter() {
+ let xs = [0, 1, 1, 1, 2, 1, 3, 5, 6];
+
+ let mut r1 = rciter(xs.iter().cloned());
+ let mut r2 = r1.clone();
+ assert_eq!(r1.next(), Some(0));
+ assert_eq!(r2.next(), Some(1));
+ let mut z = r1.zip(r2);
+ assert_eq!(z.next(), Some((1, 1)));
+ assert_eq!(z.next(), Some((2, 1)));
+ assert_eq!(z.next(), Some((3, 5)));
+ assert_eq!(z.next(), None);
+
+ // test intoiterator
+ let r1 = rciter(0..5);
+ let mut z = izip!(&r1, r1);
+ assert_eq!(z.next(), Some((0, 1)));
+}
+
+#[allow(deprecated)]
+#[test]
+fn trait_pointers() {
+ struct ByRef<'r, I: ?Sized>(&'r mut I) where I: 'r;
+
+ impl<'r, X, I: ?Sized> Iterator for ByRef<'r, I> where
+ I: 'r + Iterator<Item=X>
+ {
+ type Item = X;
+ fn next(&mut self) -> Option<X>
+ {
+ self.0.next()
+ }
+ }
+
+ let mut it = Box::new(0..10) as Box<Iterator<Item=i32>>;
+ assert_eq!(it.next(), Some(0));
+
+ {
+ /* make sure foreach works on non-Sized */
+ let jt: &mut Iterator<Item = i32> = &mut *it;
+ assert_eq!(jt.next(), Some(1));
+
+ {
+ let mut r = ByRef(jt);
+ assert_eq!(r.next(), Some(2));
+ }
+
+ assert_eq!(jt.find_position(|x| *x == 4), Some((1, 4)));
+ jt.foreach(|_| ());
+ }
+}
+
+#[test]
+fn merge_by() {
+ let odd : Vec<(u32, &str)> = vec![(1, "hello"), (3, "world"), (5, "!")];
+ let even = vec![(2, "foo"), (4, "bar"), (6, "baz")];
+ let expected = vec![(1, "hello"), (2, "foo"), (3, "world"), (4, "bar"), (5, "!"), (6, "baz")];
+ let results = odd.iter().merge_by(even.iter(), |a, b| a.0 <= b.0);
+ it::assert_equal(results, expected.iter());
+}
+
+#[test]
+fn merge_by_btree() {
+ use std::collections::BTreeMap;
+ let mut bt1 = BTreeMap::new();
+ bt1.insert("hello", 1);
+ bt1.insert("world", 3);
+ let mut bt2 = BTreeMap::new();
+ bt2.insert("foo", 2);
+ bt2.insert("bar", 4);
+ let results = bt1.into_iter().merge_by(bt2.into_iter(), |a, b| a.0 <= b.0 );
+ let expected = vec![("bar", 4), ("foo", 2), ("hello", 1), ("world", 3)];
+ it::assert_equal(results, expected.into_iter());
+}
+
+#[allow(deprecated)]
+#[test]
+fn kmerge() {
+ let its = (0..4).map(|s| (s..10).step(4));
+
+ it::assert_equal(its.kmerge(), 0..10);
+}
+
+#[allow(deprecated)]
+#[test]
+fn kmerge_2() {
+ let its = vec![3, 2, 1, 0].into_iter().map(|s| (s..10).step(4));
+
+ it::assert_equal(its.kmerge(), 0..10);
+}
+
+#[test]
+fn kmerge_empty() {
+ let its = (0..4).map(|_| 0..0);
+ assert_eq!(its.kmerge().next(), None);
+}
+
+#[test]
+fn kmerge_size_hint() {
+ let its = (0..5).map(|_| (0..10));
+ assert_eq!(its.kmerge().size_hint(), (50, Some(50)));
+}
+
+#[test]
+fn kmerge_empty_size_hint() {
+ let its = (0..5).map(|_| (0..0));
+ assert_eq!(its.kmerge().size_hint(), (0, Some(0)));
+}
+
+#[test]
+fn join() {
+ let many = [1, 2, 3];
+ let one = [1];
+ let none: Vec<i32> = vec![];
+
+ assert_eq!(many.iter().join(", "), "1, 2, 3");
+ assert_eq!( one.iter().join(", "), "1");
+ assert_eq!(none.iter().join(", "), "");
+}
+
+#[test]
+fn sorted_by() {
+ let sc = [3, 4, 1, 2].iter().cloned().sorted_by(|&a, &b| {
+ a.cmp(&b)
+ });
+ it::assert_equal(sc, vec![1, 2, 3, 4]);
+
+ let v = (0..5).sorted_by(|&a, &b| a.cmp(&b).reverse());
+ it::assert_equal(v, vec![4, 3, 2, 1, 0]);
+}
+
+#[test]
+fn sorted_by_key() {
+ let sc = [3, 4, 1, 2].iter().cloned().sorted_by_key(|&x| x);
+ it::assert_equal(sc, vec![1, 2, 3, 4]);
+
+ let v = (0..5).sorted_by_key(|&x| -x);
+ it::assert_equal(v, vec![4, 3, 2, 1, 0]);
+}
+
+#[test]
+fn test_multipeek() {
+ let nums = vec![1u8,2,3,4,5];
+
+ let mp = multipeek(nums.iter().map(|&x| x));
+ assert_eq!(nums, mp.collect::<Vec<_>>());
+
+ let mut mp = multipeek(nums.iter().map(|&x| x));
+ assert_eq!(mp.peek(), Some(&1));
+ assert_eq!(mp.next(), Some(1));
+ assert_eq!(mp.peek(), Some(&2));
+ assert_eq!(mp.peek(), Some(&3));
+ assert_eq!(mp.next(), Some(2));
+ assert_eq!(mp.peek(), Some(&3));
+ assert_eq!(mp.peek(), Some(&4));
+ assert_eq!(mp.peek(), Some(&5));
+ assert_eq!(mp.peek(), None);
+ assert_eq!(mp.next(), Some(3));
+ assert_eq!(mp.next(), Some(4));
+ assert_eq!(mp.peek(), Some(&5));
+ assert_eq!(mp.peek(), None);
+ assert_eq!(mp.next(), Some(5));
+ assert_eq!(mp.next(), None);
+ assert_eq!(mp.peek(), None);
+
+}
+
+#[test]
+fn test_multipeek_reset() {
+ let data = [1, 2, 3, 4];
+
+ let mut mp = multipeek(cloned(&data));
+ assert_eq!(mp.peek(), Some(&1));
+ assert_eq!(mp.next(), Some(1));
+ assert_eq!(mp.peek(), Some(&2));
+ assert_eq!(mp.peek(), Some(&3));
+ mp.reset_peek();
+ assert_eq!(mp.peek(), Some(&2));
+ assert_eq!(mp.next(), Some(2));
+}
+
+#[test]
+fn test_multipeek_peeking_next() {
+ use it::PeekingNext;
+ let nums = vec![1u8,2,3,4,5,6,7];
+
+ let mut mp = multipeek(nums.iter().map(|&x| x));
+ assert_eq!(mp.peeking_next(|&x| x != 0), Some(1));
+ assert_eq!(mp.next(), Some(2));
+ assert_eq!(mp.peek(), Some(&3));
+ assert_eq!(mp.peek(), Some(&4));
+ assert_eq!(mp.peeking_next(|&x| x == 3), Some(3));
+ assert_eq!(mp.peek(), Some(&4));
+ assert_eq!(mp.peeking_next(|&x| x != 4), None);
+ assert_eq!(mp.peeking_next(|&x| x == 4), Some(4));
+ assert_eq!(mp.peek(), Some(&5));
+ assert_eq!(mp.peek(), Some(&6));
+ assert_eq!(mp.peeking_next(|&x| x != 5), None);
+ assert_eq!(mp.peek(), Some(&7));
+ assert_eq!(mp.peeking_next(|&x| x == 5), Some(5));
+ assert_eq!(mp.peeking_next(|&x| x == 6), Some(6));
+ assert_eq!(mp.peek(), Some(&7));
+ assert_eq!(mp.peek(), None);
+ assert_eq!(mp.next(), Some(7));
+ assert_eq!(mp.peek(), None);
+}
+
+#[test]
+fn pad_using() {
+ it::assert_equal((0..0).pad_using(1, |_| 1), 1..2);
+
+ let v: Vec<usize> = vec![0, 1, 2];
+ let r = v.into_iter().pad_using(5, |n| n);
+ it::assert_equal(r, vec![0, 1, 2, 3, 4]);
+
+ let v: Vec<usize> = vec![0, 1, 2];
+ let r = v.into_iter().pad_using(1, |_| panic!());
+ it::assert_equal(r, vec![0, 1, 2]);
+}
+
+#[test]
+fn group_by() {
+ for (ch1, sub) in &"AABBCCC".chars().group_by(|&x| x) {
+ for ch2 in sub {
+ assert_eq!(ch1, ch2);
+ }
+ }
+
+ for (ch1, sub) in &"AAABBBCCCCDDDD".chars().group_by(|&x| x) {
+ for ch2 in sub {
+ assert_eq!(ch1, ch2);
+ if ch1 == 'C' {
+ break;
+ }
+ }
+ }
+
+ let toupper = |ch: &char| ch.to_uppercase().nth(0).unwrap();
+
+ // try all possible orderings
+ for indices in permutohedron::Heap::new(&mut [0, 1, 2, 3]) {
+ let groups = "AaaBbbccCcDDDD".chars().group_by(&toupper);
+ let mut subs = groups.into_iter().collect_vec();
+
+ for &idx in &indices[..] {
+ let (key, text) = match idx {
+ 0 => ('A', "Aaa".chars()),
+ 1 => ('B', "Bbb".chars()),
+ 2 => ('C', "ccCc".chars()),
+ 3 => ('D', "DDDD".chars()),
+ _ => unreachable!(),
+ };
+ assert_eq!(key, subs[idx].0);
+ it::assert_equal(&mut subs[idx].1, text);
+ }
+ }
+
+ let groups = "AAABBBCCCCDDDD".chars().group_by(|&x| x);
+ let mut subs = groups.into_iter().map(|(_, g)| g).collect_vec();
+
+ let sd = subs.pop().unwrap();
+ let sc = subs.pop().unwrap();
+ let sb = subs.pop().unwrap();
+ let sa = subs.pop().unwrap();
+ for (a, b, c, d) in multizip((sa, sb, sc, sd)) {
+ assert_eq!(a, 'A');
+ assert_eq!(b, 'B');
+ assert_eq!(c, 'C');
+ assert_eq!(d, 'D');
+ }
+
+ // check that the key closure is called exactly n times
+ {
+ let mut ntimes = 0;
+ let text = "AABCCC";
+ for (_, sub) in &text.chars().group_by(|&x| { ntimes += 1; x}) {
+ for _ in sub {
+ }
+ }
+ assert_eq!(ntimes, text.len());
+ }
+
+ {
+ let mut ntimes = 0;
+ let text = "AABCCC";
+ for _ in &text.chars().group_by(|&x| { ntimes += 1; x}) {
+ }
+ assert_eq!(ntimes, text.len());
+ }
+
+ {
+ let text = "ABCCCDEEFGHIJJKK";
+ let gr = text.chars().group_by(|&x| x);
+ it::assert_equal(gr.into_iter().flat_map(|(_, sub)| sub), text.chars());
+ }
+}
+
+#[test]
+fn group_by_lazy_2() {
+ let data = vec![0, 1];
+ let groups = data.iter().group_by(|k| *k);
+ let gs = groups.into_iter().collect_vec();
+ it::assert_equal(data.iter(), gs.into_iter().flat_map(|(_k, g)| g));
+
+ let data = vec![0, 1, 1, 0, 0];
+ let groups = data.iter().group_by(|k| *k);
+ let mut gs = groups.into_iter().collect_vec();
+ gs[1..].reverse();
+ it::assert_equal(&[0, 0, 0, 1, 1], gs.into_iter().flat_map(|(_, g)| g));
+
+ let grouper = data.iter().group_by(|k| *k);
+ let mut groups = Vec::new();
+ for (k, group) in &grouper {
+ if *k == 1 {
+ groups.push(group);
+ }
+ }
+ it::assert_equal(&mut groups[0], &[1, 1]);
+
+ let data = vec![0, 0, 0, 1, 1, 0, 0, 2, 2, 3, 3];
+ let grouper = data.iter().group_by(|k| *k);
+ let mut groups = Vec::new();
+ for (i, (_, group)) in grouper.into_iter().enumerate() {
+ if i < 2 {
+ groups.push(group);
+ } else if i < 4 {
+ for _ in group {
+ }
+ } else {
+ groups.push(group);
+ }
+ }
+ it::assert_equal(&mut groups[0], &[0, 0, 0]);
+ it::assert_equal(&mut groups[1], &[1, 1]);
+ it::assert_equal(&mut groups[2], &[3, 3]);
+
+ // use groups as chunks
+ let data = vec![0, 0, 0, 1, 1, 0, 0, 2, 2, 3, 3];
+ let mut i = 0;
+ let grouper = data.iter().group_by(move |_| { let k = i / 3; i += 1; k });
+ for (i, group) in &grouper {
+ match i {
+ 0 => it::assert_equal(group, &[0, 0, 0]),
+ 1 => it::assert_equal(group, &[1, 1, 0]),
+ 2 => it::assert_equal(group, &[0, 2, 2]),
+ 3 => it::assert_equal(group, &[3, 3]),
+ _ => unreachable!(),
+ }
+ }
+}
+
+#[test]
+fn group_by_lazy_3() {
+ // test consuming each group on the lap after it was produced
+ let data = vec![0, 0, 0, 1, 1, 0, 0, 1, 1, 2, 2];
+ let grouper = data.iter().group_by(|elt| *elt);
+ let mut last = None;
+ for (key, group) in &grouper {
+ if let Some(gr) = last.take() {
+ for elt in gr {
+ assert!(elt != key && i32::abs(elt - key) == 1);
+ }
+ }
+ last = Some(group);
+ }
+}
+
+#[test]
+fn chunks() {
+ let data = vec![0, 0, 0, 1, 1, 0, 0, 2, 2, 3, 3];
+ let grouper = data.iter().chunks(3);
+ for (i, chunk) in grouper.into_iter().enumerate() {
+ match i {
+ 0 => it::assert_equal(chunk, &[0, 0, 0]),
+ 1 => it::assert_equal(chunk, &[1, 1, 0]),
+ 2 => it::assert_equal(chunk, &[0, 2, 2]),
+ 3 => it::assert_equal(chunk, &[3, 3]),
+ _ => unreachable!(),
+ }
+ }
+}
+
+#[test]
+fn concat_empty() {
+ let data: Vec<Vec<()>> = Vec::new();
+ assert_eq!(data.into_iter().concat(), Vec::new())
+}
+
+#[test]
+fn concat_non_empty() {
+ let data = vec![vec![1,2,3], vec![4,5,6], vec![7,8,9]];
+ assert_eq!(data.into_iter().concat(), vec![1,2,3,4,5,6,7,8,9])
+}
+
+#[test]
+fn combinations() {
+ assert!((1..3).combinations(5).next().is_none());
+
+ let it = (1..3).combinations(2);
+ it::assert_equal(it, vec![
+ vec![1, 2],
+ ]);
+
+ let it = (1..5).combinations(2);
+ it::assert_equal(it, vec![
+ vec![1, 2],
+ vec![1, 3],
+ vec![1, 4],
+ vec![2, 3],
+ vec![2, 4],
+ vec![3, 4],
+ ]);
+
+ it::assert_equal((0..0).tuple_combinations::<(_, _)>(), <Vec<_>>::new());
+ it::assert_equal((0..1).tuple_combinations::<(_, _)>(), <Vec<_>>::new());
+ it::assert_equal((0..2).tuple_combinations::<(_, _)>(), vec![(0, 1)]);
+
+ it::assert_equal((0..0).combinations(2), <Vec<Vec<_>>>::new());
+ it::assert_equal((0..1).combinations(1), vec![vec![0]]);
+ it::assert_equal((0..2).combinations(1), vec![vec![0], vec![1]]);
+ it::assert_equal((0..2).combinations(2), vec![vec![0, 1]]);
+}
+
+#[test]
+fn combinations_of_too_short() {
+ for i in 1..10 {
+ assert!((0..0).combinations(i).next().is_none());
+ assert!((0..i - 1).combinations(i).next().is_none());
+ }
+}
+
+
+#[test]
+fn combinations_zero() {
+ it::assert_equal((1..3).combinations(0), vec![vec![]]);
+}
+
+#[test]
+fn combinations_with_replacement() {
+ // Pool smaller than n
+ it::assert_equal((0..1).combinations_with_replacement(2), vec![vec![0, 0]]);
+ // Pool larger than n
+ it::assert_equal(
+ (0..3).combinations_with_replacement(2),
+ vec![
+ vec![0, 0],
+ vec![0, 1],
+ vec![0, 2],
+ vec![1, 1],
+ vec![1, 2],
+ vec![2, 2],
+ ],
+ );
+ // Zero size
+ it::assert_equal(
+ (0..3).combinations_with_replacement(0),
+ <Vec<Vec<_>>>::new(),
+ );
+ // Empty pool
+ it::assert_equal(
+ (0..0).combinations_with_replacement(2),
+ <Vec<Vec<_>>>::new(),
+ );
+}
+
+#[test]
+fn diff_mismatch() {
+ let a = vec![1, 2, 3, 4];
+ let b = vec![1.0, 5.0, 3.0, 4.0];
+ let b_map = b.into_iter().map(|f| f as i32);
+ let diff = it::diff_with(a.iter(), b_map, |a, b| *a == b);
+
+ assert!(match diff {
+ Some(it::Diff::FirstMismatch(1, _, from_diff)) =>
+ from_diff.collect::<Vec<_>>() == vec![5, 3, 4],
+ _ => false,
+ });
+}
+
+#[test]
+fn diff_longer() {
+ let a = vec![1, 2, 3, 4];
+ let b = vec![1.0, 2.0, 3.0, 4.0, 5.0, 6.0];
+ let b_map = b.into_iter().map(|f| f as i32);
+ let diff = it::diff_with(a.iter(), b_map, |a, b| *a == b);
+
+ assert!(match diff {
+ Some(it::Diff::Longer(_, remaining)) =>
+ remaining.collect::<Vec<_>>() == vec![5, 6],
+ _ => false,
+ });
+}
+
+#[test]
+fn diff_shorter() {
+ let a = vec![1, 2, 3, 4];
+ let b = vec![1.0, 2.0];
+ let b_map = b.into_iter().map(|f| f as i32);
+ let diff = it::diff_with(a.iter(), b_map, |a, b| *a == b);
+
+ assert!(match diff {
+ Some(it::Diff::Shorter(len, _)) => len == 2,
+ _ => false,
+ });
+}
+
+#[test]
+fn minmax() {
+ use std::cmp::Ordering;
+ use it::MinMaxResult;
+
+ // A peculiar type: Equality compares both tuple items, but ordering only the
+ // first item. This is so we can check the stability property easily.
+ #[derive(Clone, Debug, PartialEq, Eq)]
+ struct Val(u32, u32);
+
+ impl PartialOrd<Val> for Val {
+ fn partial_cmp(&self, other: &Val) -> Option<Ordering> {
+ self.0.partial_cmp(&other.0)
+ }
+ }
+
+ impl Ord for Val {
+ fn cmp(&self, other: &Val) -> Ordering {
+ self.0.cmp(&other.0)
+ }
+ }
+
+ assert_eq!(None::<Option<u32>>.iter().minmax(), MinMaxResult::NoElements);
+
+ assert_eq!(Some(1u32).iter().minmax(), MinMaxResult::OneElement(&1));
+
+ let data = vec![Val(0, 1), Val(2, 0), Val(0, 2), Val(1, 0), Val(2, 1)];
+
+ let minmax = data.iter().minmax();
+ assert_eq!(minmax, MinMaxResult::MinMax(&Val(0, 1), &Val(2, 1)));
+
+ let (min, max) = data.iter().minmax_by_key(|v| v.1).into_option().unwrap();
+ assert_eq!(min, &Val(2, 0));
+ assert_eq!(max, &Val(0, 2));
+
+ let (min, max) = data.iter().minmax_by(|x, y| x.1.cmp(&y.1)).into_option().unwrap();
+ assert_eq!(min, &Val(2, 0));
+ assert_eq!(max, &Val(0, 2));
+}
+
+#[test]
+fn format() {
+ let data = [0, 1, 2, 3];
+ let ans1 = "0, 1, 2, 3";
+ let ans2 = "0--1--2--3";
+
+ let t1 = format!("{}", data.iter().format(", "));
+ assert_eq!(t1, ans1);
+ let t2 = format!("{:?}", data.iter().format("--"));
+ assert_eq!(t2, ans2);
+
+ let dataf = [1.1, 2.71828, -22.];
+ let t3 = format!("{:.2e}", dataf.iter().format(", "));
+ assert_eq!(t3, "1.10e0, 2.72e0, -2.20e1");
+}
+
+#[test]
+fn while_some() {
+ let ns = (1..10).map(|x| if x % 5 != 0 { Some(x) } else { None })
+ .while_some();
+ it::assert_equal(ns, vec![1, 2, 3, 4]);
+}
+
+#[allow(deprecated)]
+#[test]
+fn fold_while() {
+ let mut iterations = 0;
+ let vec = vec![1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
+ let sum = vec.into_iter().fold_while(0, |acc, item| {
+ iterations += 1;
+ let new_sum = acc.clone() + item;
+ if new_sum <= 20 {
+ FoldWhile::Continue(new_sum)
+ } else {
+ FoldWhile::Done(acc)
+ }
+ }).into_inner();
+ assert_eq!(iterations, 6);
+ assert_eq!(sum, 15);
+}
+
+#[test]
+fn tree_fold1() {
+ let x = [
+ "",
+ "0",
+ "0 1 x",
+ "0 1 x 2 x",
+ "0 1 x 2 3 x x",
+ "0 1 x 2 3 x x 4 x",
+ "0 1 x 2 3 x x 4 5 x x",
+ "0 1 x 2 3 x x 4 5 x 6 x x",
+ "0 1 x 2 3 x x 4 5 x 6 7 x x x",
+ "0 1 x 2 3 x x 4 5 x 6 7 x x x 8 x",
+ "0 1 x 2 3 x x 4 5 x 6 7 x x x 8 9 x x",
+ "0 1 x 2 3 x x 4 5 x 6 7 x x x 8 9 x 10 x x",
+ "0 1 x 2 3 x x 4 5 x 6 7 x x x 8 9 x 10 11 x x x",
+ "0 1 x 2 3 x x 4 5 x 6 7 x x x 8 9 x 10 11 x x 12 x x",
+ "0 1 x 2 3 x x 4 5 x 6 7 x x x 8 9 x 10 11 x x 12 13 x x x",
+ "0 1 x 2 3 x x 4 5 x 6 7 x x x 8 9 x 10 11 x x 12 13 x 14 x x x",
+ "0 1 x 2 3 x x 4 5 x 6 7 x x x 8 9 x 10 11 x x 12 13 x 14 15 x x x x",
+ ];
+ for (i, &s) in x.iter().enumerate() {
+ let expected = if s == "" { None } else { Some(s.to_string()) };
+ let num_strings = (0..i).map(|x| x.to_string());
+ let actual = num_strings.tree_fold1(|a, b| format!("{} {} x", a, b));
+ assert_eq!(actual, expected);
+ }
+}
projects / rustc.git / blobdiff