rust/src/libcollections/dlist.rs
2014-02-20 16:03:58 +08:00

1206 lines
33 KiB
Rust

// Copyright 2012-2013 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
//! A doubly-linked list with owned nodes.
//!
//! The DList allows pushing and popping elements at either end.
//!
//! DList implements the trait Deque. It should be imported with `use
//! extra::container::Deque`.
// DList is constructed like a singly-linked list over the field `next`.
// including the last link being None; each Node owns its `next` field.
//
// Backlinks over DList::prev are raw pointers that form a full chain in
// the reverse direction.
use std::cast;
use std::mem::{replace, swap};
use std::ptr;
use std::iter::Rev;
use std::iter;
use deque::Deque;
use serialize::{Encodable, Decodable, Encoder, Decoder};
/// A doubly-linked list.
pub struct DList<T> {
priv length: uint,
priv list_head: Link<T>,
priv list_tail: Rawlink<Node<T>>,
}
type Link<T> = Option<~Node<T>>;
struct Rawlink<T> { p: *mut T }
struct Node<T> {
next: Link<T>,
prev: Rawlink<Node<T>>,
value: T,
}
/// Double-ended DList iterator
pub struct Items<'a, T> {
priv head: &'a Link<T>,
priv tail: Rawlink<Node<T>>,
priv nelem: uint,
}
// FIXME #11820: the &'a Option<> of the Link stops clone working.
impl<'a, T> Clone for Items<'a, T> {
fn clone(&self) -> Items<'a, T> { *self }
}
/// Double-ended mutable DList iterator
pub struct MutItems<'a, T> {
priv list: &'a mut DList<T>,
priv head: Rawlink<Node<T>>,
priv tail: Rawlink<Node<T>>,
priv nelem: uint,
}
/// DList consuming iterator
#[deriving(Clone)]
pub struct MoveItems<T> {
priv list: DList<T>
}
/// Rawlink is a type like Option<T> but for holding a raw pointer
impl<T> Rawlink<T> {
/// Like Option::None for Rawlink
fn none() -> Rawlink<T> {
Rawlink{p: ptr::mut_null()}
}
/// Like Option::Some for Rawlink
fn some(n: &mut T) -> Rawlink<T> {
Rawlink{p: n}
}
/// Convert the `Rawlink` into an Option value
fn resolve_immut(&self) -> Option<&T> {
unsafe { self.p.to_option() }
}
/// Convert the `Rawlink` into an Option value
fn resolve(&mut self) -> Option<&mut T> {
if self.p.is_null() {
None
} else {
Some(unsafe { cast::transmute(self.p) })
}
}
/// Return the `Rawlink` and replace with `Rawlink::none()`
fn take(&mut self) -> Rawlink<T> {
replace(self, Rawlink::none())
}
}
impl<T> Clone for Rawlink<T> {
#[inline]
fn clone(&self) -> Rawlink<T> {
Rawlink{p: self.p}
}
}
impl<T> Node<T> {
fn new(v: T) -> Node<T> {
Node{value: v, next: None, prev: Rawlink::none()}
}
}
/// Set the .prev field on `next`, then return `Some(next)`
fn link_with_prev<T>(mut next: ~Node<T>, prev: Rawlink<Node<T>>) -> Link<T> {
next.prev = prev;
Some(next)
}
impl<T> Container for DList<T> {
/// O(1)
#[inline]
fn is_empty(&self) -> bool {
self.list_head.is_none()
}
/// O(1)
#[inline]
fn len(&self) -> uint {
self.length
}
}
impl<T> Mutable for DList<T> {
/// Remove all elements from the DList
///
/// O(N)
#[inline]
fn clear(&mut self) {
*self = DList::new()
}
}
// private methods
impl<T> DList<T> {
/// Add a Node first in the list
#[inline]
fn push_front_node(&mut self, mut new_head: ~Node<T>) {
match self.list_head {
None => {
self.list_tail = Rawlink::some(new_head);
self.list_head = link_with_prev(new_head, Rawlink::none());
}
Some(ref mut head) => {
new_head.prev = Rawlink::none();
head.prev = Rawlink::some(new_head);
swap(head, &mut new_head);
head.next = Some(new_head);
}
}
self.length += 1;
}
/// Remove the first Node and return it, or None if the list is empty
#[inline]
fn pop_front_node(&mut self) -> Option<~Node<T>> {
self.list_head.take().map(|mut front_node| {
self.length -= 1;
match front_node.next.take() {
Some(node) => self.list_head = link_with_prev(node, Rawlink::none()),
None => self.list_tail = Rawlink::none()
}
front_node
})
}
/// Add a Node last in the list
#[inline]
fn push_back_node(&mut self, mut new_tail: ~Node<T>) {
match self.list_tail.resolve() {
None => return self.push_front_node(new_tail),
Some(tail) => {
self.list_tail = Rawlink::some(new_tail);
tail.next = link_with_prev(new_tail, Rawlink::some(tail));
}
}
self.length += 1;
}
/// Remove the last Node and return it, or None if the list is empty
#[inline]
fn pop_back_node(&mut self) -> Option<~Node<T>> {
self.list_tail.resolve().map_or(None, |tail| {
self.length -= 1;
self.list_tail = tail.prev;
match tail.prev.resolve() {
None => self.list_head.take(),
Some(tail_prev) => tail_prev.next.take()
}
})
}
}
impl<T> Deque<T> for DList<T> {
/// Provide a reference to the front element, or None if the list is empty
#[inline]
fn front<'a>(&'a self) -> Option<&'a T> {
self.list_head.as_ref().map(|head| &head.value)
}
/// Provide a mutable reference to the front element, or None if the list is empty
#[inline]
fn front_mut<'a>(&'a mut self) -> Option<&'a mut T> {
self.list_head.as_mut().map(|head| &mut head.value)
}
/// Provide a reference to the back element, or None if the list is empty
#[inline]
fn back<'a>(&'a self) -> Option<&'a T> {
let tmp = self.list_tail.resolve_immut(); // FIXME: #3511: shouldn't need variable
tmp.as_ref().map(|tail| &tail.value)
}
/// Provide a mutable reference to the back element, or None if the list is empty
#[inline]
fn back_mut<'a>(&'a mut self) -> Option<&'a mut T> {
let tmp: Option<&'a mut Node<T>> =
self.list_tail.resolve(); // FIXME: #3511: shouldn't need variable
tmp.map(|tail| &mut tail.value)
}
/// Add an element first in the list
///
/// O(1)
fn push_front(&mut self, elt: T) {
self.push_front_node(~Node::new(elt))
}
/// Remove the first element and return it, or None if the list is empty
///
/// O(1)
fn pop_front(&mut self) -> Option<T> {
self.pop_front_node().map(|~Node{value, ..}| value)
}
/// Add an element last in the list
///
/// O(1)
fn push_back(&mut self, elt: T) {
self.push_back_node(~Node::new(elt))
}
/// Remove the last element and return it, or None if the list is empty
///
/// O(1)
fn pop_back(&mut self) -> Option<T> {
self.pop_back_node().map(|~Node{value, ..}| value)
}
}
impl<T> DList<T> {
/// Create an empty DList
#[inline]
pub fn new() -> DList<T> {
DList{list_head: None, list_tail: Rawlink::none(), length: 0}
}
/// Move the last element to the front of the list.
///
/// If the list is empty, do nothing.
#[inline]
pub fn rotate_forward(&mut self) {
self.pop_back_node().map(|tail| {
self.push_front_node(tail)
});
}
/// Move the first element to the back of the list.
///
/// If the list is empty, do nothing.
#[inline]
pub fn rotate_backward(&mut self) {
self.pop_front_node().map(|head| {
self.push_back_node(head)
});
}
/// Add all elements from `other` to the end of the list
///
/// O(1)
pub fn append(&mut self, mut other: DList<T>) {
match self.list_tail.resolve() {
None => *self = other,
Some(tail) => {
// Carefully empty `other`.
let o_tail = other.list_tail.take();
let o_length = other.length;
match other.list_head.take() {
None => return,
Some(node) => {
tail.next = link_with_prev(node, self.list_tail);
self.list_tail = o_tail;
self.length += o_length;
}
}
}
}
}
/// Add all elements from `other` to the beginning of the list
///
/// O(1)
#[inline]
pub fn prepend(&mut self, mut other: DList<T>) {
swap(self, &mut other);
self.append(other);
}
/// Insert `elt` before the first `x` in the list where `f(x, elt)` is true,
/// or at the end.
///
/// O(N)
pub fn insert_when(&mut self, elt: T, f: |&T, &T| -> bool) {
{
let mut it = self.mut_iter();
loop {
match it.peek_next() {
None => break,
Some(x) => if f(x, &elt) { break }
}
it.next();
}
it.insert_next(elt);
}
}
/// Merge DList `other` into this DList, using the function `f`.
/// Iterate the both DList with `a` from self and `b` from `other`, and
/// put `a` in the result if `f(a, b)` is true, else `b`.
///
/// O(max(N, M))
pub fn merge(&mut self, mut other: DList<T>, f: |&T, &T| -> bool) {
{
let mut it = self.mut_iter();
loop {
let take_a = match (it.peek_next(), other.front()) {
(_ , None) => return,
(None, _ ) => break,
(Some(ref mut x), Some(y)) => f(*x, y),
};
if take_a {
it.next();
} else {
it.insert_next_node(other.pop_front_node().unwrap());
}
}
}
self.append(other);
}
/// Provide a forward iterator
#[inline]
pub fn iter<'a>(&'a self) -> Items<'a, T> {
Items{nelem: self.len(), head: &self.list_head, tail: self.list_tail}
}
/// Provide a reverse iterator
#[inline]
pub fn rev_iter<'a>(&'a self) -> Rev<Items<'a, T>> {
self.iter().rev()
}
/// Provide a forward iterator with mutable references
#[inline]
pub fn mut_iter<'a>(&'a mut self) -> MutItems<'a, T> {
let head_raw = match self.list_head {
Some(ref mut h) => Rawlink::some(*h),
None => Rawlink::none(),
};
MutItems{
nelem: self.len(),
head: head_raw,
tail: self.list_tail,
list: self
}
}
/// Provide a reverse iterator with mutable references
#[inline]
pub fn mut_rev_iter<'a>(&'a mut self) -> Rev<MutItems<'a, T>> {
self.mut_iter().rev()
}
/// Consume the list into an iterator yielding elements by value
#[inline]
pub fn move_iter(self) -> MoveItems<T> {
MoveItems{list: self}
}
/// Consume the list into an iterator yielding elements by value, in reverse
#[inline]
pub fn move_rev_iter(self) -> Rev<MoveItems<T>> {
self.move_iter().rev()
}
}
impl<T: Ord> DList<T> {
/// Insert `elt` sorted in ascending order
///
/// O(N)
#[inline]
pub fn insert_ordered(&mut self, elt: T) {
self.insert_when(elt, |a, b| a >= b)
}
}
#[unsafe_destructor]
impl<T> Drop for DList<T> {
fn drop(&mut self) {
// Dissolve the dlist in backwards direction
// Just dropping the list_head can lead to stack exhaustion
// when length is >> 1_000_000
let mut tail = self.list_tail;
loop {
match tail.resolve() {
None => break,
Some(prev) => {
prev.next.take(); // release ~Node<T>
tail = prev.prev;
}
}
}
self.length = 0;
self.list_head = None;
self.list_tail = Rawlink::none();
}
}
impl<'a, A> Iterator<&'a A> for Items<'a, A> {
#[inline]
fn next(&mut self) -> Option<&'a A> {
if self.nelem == 0 {
return None;
}
self.head.as_ref().map(|head| {
self.nelem -= 1;
self.head = &head.next;
&head.value
})
}
#[inline]
fn size_hint(&self) -> (uint, Option<uint>) {
(self.nelem, Some(self.nelem))
}
}
impl<'a, A> DoubleEndedIterator<&'a A> for Items<'a, A> {
#[inline]
fn next_back(&mut self) -> Option<&'a A> {
if self.nelem == 0 {
return None;
}
let tmp = self.tail.resolve_immut(); // FIXME: #3511: shouldn't need variable
tmp.as_ref().map(|prev| {
self.nelem -= 1;
self.tail = prev.prev;
&prev.value
})
}
}
impl<'a, A> ExactSize<&'a A> for Items<'a, A> {}
impl<'a, A> Iterator<&'a mut A> for MutItems<'a, A> {
#[inline]
fn next(&mut self) -> Option<&'a mut A> {
if self.nelem == 0 {
return None;
}
self.head.resolve().map(|next| {
self.nelem -= 1;
self.head = match next.next {
Some(ref mut node) => Rawlink::some(&mut **node),
None => Rawlink::none(),
};
&mut next.value
})
}
#[inline]
fn size_hint(&self) -> (uint, Option<uint>) {
(self.nelem, Some(self.nelem))
}
}
impl<'a, A> DoubleEndedIterator<&'a mut A> for MutItems<'a, A> {
#[inline]
fn next_back(&mut self) -> Option<&'a mut A> {
if self.nelem == 0 {
return None;
}
self.tail.resolve().map(|prev| {
self.nelem -= 1;
self.tail = prev.prev;
&mut prev.value
})
}
}
impl<'a, A> ExactSize<&'a mut A> for MutItems<'a, A> {}
/// Allow mutating the DList while iterating
pub trait ListInsertion<A> {
/// Insert `elt` just after to the element most recently returned by `.next()`
///
/// The inserted element does not appear in the iteration.
fn insert_next(&mut self, elt: A);
/// Provide a reference to the next element, without changing the iterator
fn peek_next<'a>(&'a mut self) -> Option<&'a mut A>;
}
// private methods for MutItems
impl<'a, A> MutItems<'a, A> {
fn insert_next_node(&mut self, mut ins_node: ~Node<A>) {
// Insert before `self.head` so that it is between the
// previously yielded element and self.head.
//
// The inserted node will not appear in further iteration.
match self.head.resolve() {
None => { self.list.push_back_node(ins_node); }
Some(node) => {
let prev_node = match node.prev.resolve() {
None => return self.list.push_front_node(ins_node),
Some(prev) => prev,
};
let node_own = prev_node.next.take_unwrap();
ins_node.next = link_with_prev(node_own, Rawlink::some(ins_node));
prev_node.next = link_with_prev(ins_node, Rawlink::some(prev_node));
self.list.length += 1;
}
}
}
}
impl<'a, A> ListInsertion<A> for MutItems<'a, A> {
#[inline]
fn insert_next(&mut self, elt: A) {
self.insert_next_node(~Node::new(elt))
}
#[inline]
fn peek_next<'a>(&'a mut self) -> Option<&'a mut A> {
if self.nelem == 0 {
return None
}
self.head.resolve().map(|head| &mut head.value)
}
}
impl<A> Iterator<A> for MoveItems<A> {
#[inline]
fn next(&mut self) -> Option<A> { self.list.pop_front() }
#[inline]
fn size_hint(&self) -> (uint, Option<uint>) {
(self.list.length, Some(self.list.length))
}
}
impl<A> DoubleEndedIterator<A> for MoveItems<A> {
#[inline]
fn next_back(&mut self) -> Option<A> { self.list.pop_back() }
}
impl<A> FromIterator<A> for DList<A> {
fn from_iterator<T: Iterator<A>>(iterator: &mut T) -> DList<A> {
let mut ret = DList::new();
ret.extend(iterator);
ret
}
}
impl<A> Extendable<A> for DList<A> {
fn extend<T: Iterator<A>>(&mut self, iterator: &mut T) {
for elt in *iterator { self.push_back(elt); }
}
}
impl<A: Eq> Eq for DList<A> {
fn eq(&self, other: &DList<A>) -> bool {
self.len() == other.len() &&
iter::order::eq(self.iter(), other.iter())
}
fn ne(&self, other: &DList<A>) -> bool {
self.len() != other.len() ||
iter::order::ne(self.iter(), other.iter())
}
}
impl<A: Eq + Ord> Ord for DList<A> {
fn lt(&self, other: &DList<A>) -> bool {
iter::order::lt(self.iter(), other.iter())
}
fn le(&self, other: &DList<A>) -> bool {
iter::order::le(self.iter(), other.iter())
}
fn gt(&self, other: &DList<A>) -> bool {
iter::order::gt(self.iter(), other.iter())
}
fn ge(&self, other: &DList<A>) -> bool {
iter::order::ge(self.iter(), other.iter())
}
}
impl<A: Clone> Clone for DList<A> {
fn clone(&self) -> DList<A> {
self.iter().map(|x| x.clone()).collect()
}
}
impl<
S: Encoder,
T: Encodable<S>
> Encodable<S> for DList<T> {
fn encode(&self, s: &mut S) {
s.emit_seq(self.len(), |s| {
for (i, e) in self.iter().enumerate() {
s.emit_seq_elt(i, |s| e.encode(s));
}
})
}
}
impl<D:Decoder,T:Decodable<D>> Decodable<D> for DList<T> {
fn decode(d: &mut D) -> DList<T> {
let mut list = DList::new();
d.read_seq(|d, len| {
for i in range(0u, len) {
list.push_back(d.read_seq_elt(i, |d| Decodable::decode(d)));
}
});
list
}
}
#[cfg(test)]
mod tests {
extern crate test;
use self::test::BenchHarness;
use deque::Deque;
use std::rand;
use super::{DList, Node, ListInsertion};
pub fn check_links<T>(list: &DList<T>) {
let mut len = 0u;
let mut last_ptr: Option<&Node<T>> = None;
let mut node_ptr: &Node<T>;
match list.list_head {
None => { assert_eq!(0u, list.length); return }
Some(ref node) => node_ptr = &**node,
}
loop {
match (last_ptr, node_ptr.prev.resolve_immut()) {
(None , None ) => {}
(None , _ ) => fail!("prev link for list_head"),
(Some(p), Some(pptr)) => {
assert_eq!(p as *Node<T>, pptr as *Node<T>);
}
_ => fail!("prev link is none, not good"),
}
match node_ptr.next {
Some(ref next) => {
last_ptr = Some(node_ptr);
node_ptr = &**next;
len += 1;
}
None => {
len += 1;
break;
}
}
}
assert_eq!(len, list.length);
}
#[test]
fn test_basic() {
let mut m: DList<~int> = DList::new();
assert_eq!(m.pop_front(), None);
assert_eq!(m.pop_back(), None);
assert_eq!(m.pop_front(), None);
m.push_front(~1);
assert_eq!(m.pop_front(), Some(~1));
m.push_back(~2);
m.push_back(~3);
assert_eq!(m.len(), 2);
assert_eq!(m.pop_front(), Some(~2));
assert_eq!(m.pop_front(), Some(~3));
assert_eq!(m.len(), 0);
assert_eq!(m.pop_front(), None);
m.push_back(~1);
m.push_back(~3);
m.push_back(~5);
m.push_back(~7);
assert_eq!(m.pop_front(), Some(~1));
let mut n = DList::new();
n.push_front(2);
n.push_front(3);
{
assert_eq!(n.front().unwrap(), &3);
let x = n.front_mut().unwrap();
assert_eq!(*x, 3);
*x = 0;
}
{
assert_eq!(n.back().unwrap(), &2);
let y = n.back_mut().unwrap();
assert_eq!(*y, 2);
*y = 1;
}
assert_eq!(n.pop_front(), Some(0));
assert_eq!(n.pop_front(), Some(1));
}
#[cfg(test)]
fn generate_test() -> DList<int> {
list_from(&[0,1,2,3,4,5,6])
}
#[cfg(test)]
fn list_from<T: Clone>(v: &[T]) -> DList<T> {
v.iter().map(|x| (*x).clone()).collect()
}
#[test]
fn test_append() {
{
let mut m = DList::new();
let mut n = DList::new();
n.push_back(2);
m.append(n);
assert_eq!(m.len(), 1);
assert_eq!(m.pop_back(), Some(2));
check_links(&m);
}
{
let mut m = DList::new();
let n = DList::new();
m.push_back(2);
m.append(n);
assert_eq!(m.len(), 1);
assert_eq!(m.pop_back(), Some(2));
check_links(&m);
}
let v = ~[1,2,3,4,5];
let u = ~[9,8,1,2,3,4,5];
let mut m = list_from(v);
m.append(list_from(u));
check_links(&m);
let sum = v + u;
assert_eq!(sum.len(), m.len());
for elt in sum.move_iter() {
assert_eq!(m.pop_front(), Some(elt))
}
}
#[test]
fn test_prepend() {
{
let mut m = DList::new();
let mut n = DList::new();
n.push_back(2);
m.prepend(n);
assert_eq!(m.len(), 1);
assert_eq!(m.pop_back(), Some(2));
check_links(&m);
}
let v = ~[1,2,3,4,5];
let u = ~[9,8,1,2,3,4,5];
let mut m = list_from(v);
m.prepend(list_from(u));
check_links(&m);
let sum = u + v;
assert_eq!(sum.len(), m.len());
for elt in sum.move_iter() {
assert_eq!(m.pop_front(), Some(elt))
}
}
#[test]
fn test_rotate() {
let mut n: DList<int> = DList::new();
n.rotate_backward(); check_links(&n);
assert_eq!(n.len(), 0);
n.rotate_forward(); check_links(&n);
assert_eq!(n.len(), 0);
let v = ~[1,2,3,4,5];
let mut m = list_from(v);
m.rotate_backward(); check_links(&m);
m.rotate_forward(); check_links(&m);
assert_eq!(v.iter().collect::<~[&int]>(), m.iter().collect());
m.rotate_forward(); check_links(&m);
m.rotate_forward(); check_links(&m);
m.pop_front(); check_links(&m);
m.rotate_forward(); check_links(&m);
m.rotate_backward(); check_links(&m);
m.push_front(9); check_links(&m);
m.rotate_forward(); check_links(&m);
assert_eq!(~[3,9,5,1,2], m.move_iter().collect());
}
#[test]
fn test_iterator() {
let m = generate_test();
for (i, elt) in m.iter().enumerate() {
assert_eq!(i as int, *elt);
}
let mut n = DList::new();
assert_eq!(n.iter().next(), None);
n.push_front(4);
let mut it = n.iter();
assert_eq!(it.size_hint(), (1, Some(1)));
assert_eq!(it.next().unwrap(), &4);
assert_eq!(it.size_hint(), (0, Some(0)));
assert_eq!(it.next(), None);
}
#[test]
fn test_iterator_clone() {
let mut n = DList::new();
n.push_back(2);
n.push_back(3);
n.push_back(4);
let mut it = n.iter();
it.next();
let mut jt = it.clone();
assert_eq!(it.next(), jt.next());
assert_eq!(it.next_back(), jt.next_back());
assert_eq!(it.next(), jt.next());
}
#[test]
fn test_iterator_double_end() {
let mut n = DList::new();
assert_eq!(n.iter().next(), None);
n.push_front(4);
n.push_front(5);
n.push_front(6);
let mut it = n.iter();
assert_eq!(it.size_hint(), (3, Some(3)));
assert_eq!(it.next().unwrap(), &6);
assert_eq!(it.size_hint(), (2, Some(2)));
assert_eq!(it.next_back().unwrap(), &4);
assert_eq!(it.size_hint(), (1, Some(1)));
assert_eq!(it.next_back().unwrap(), &5);
assert_eq!(it.next_back(), None);
assert_eq!(it.next(), None);
}
#[test]
fn test_rev_iter() {
let m = generate_test();
for (i, elt) in m.rev_iter().enumerate() {
assert_eq!((6 - i) as int, *elt);
}
let mut n = DList::new();
assert_eq!(n.rev_iter().next(), None);
n.push_front(4);
let mut it = n.rev_iter();
assert_eq!(it.size_hint(), (1, Some(1)));
assert_eq!(it.next().unwrap(), &4);
assert_eq!(it.size_hint(), (0, Some(0)));
assert_eq!(it.next(), None);
}
#[test]
fn test_mut_iter() {
let mut m = generate_test();
let mut len = m.len();
for (i, elt) in m.mut_iter().enumerate() {
assert_eq!(i as int, *elt);
len -= 1;
}
assert_eq!(len, 0);
let mut n = DList::new();
assert!(n.mut_iter().next().is_none());
n.push_front(4);
n.push_back(5);
let mut it = n.mut_iter();
assert_eq!(it.size_hint(), (2, Some(2)));
assert!(it.next().is_some());
assert!(it.next().is_some());
assert_eq!(it.size_hint(), (0, Some(0)));
assert!(it.next().is_none());
}
#[test]
fn test_iterator_mut_double_end() {
let mut n = DList::new();
assert!(n.mut_iter().next_back().is_none());
n.push_front(4);
n.push_front(5);
n.push_front(6);
let mut it = n.mut_iter();
assert_eq!(it.size_hint(), (3, Some(3)));
assert_eq!(*it.next().unwrap(), 6);
assert_eq!(it.size_hint(), (2, Some(2)));
assert_eq!(*it.next_back().unwrap(), 4);
assert_eq!(it.size_hint(), (1, Some(1)));
assert_eq!(*it.next_back().unwrap(), 5);
assert!(it.next_back().is_none());
assert!(it.next().is_none());
}
#[test]
fn test_insert_prev() {
let mut m = list_from(&[0,2,4,6,8]);
let len = m.len();
{
let mut it = m.mut_iter();
it.insert_next(-2);
loop {
match it.next() {
None => break,
Some(elt) => {
it.insert_next(*elt + 1);
match it.peek_next() {
Some(x) => assert_eq!(*x, *elt + 2),
None => assert_eq!(8, *elt),
}
}
}
}
it.insert_next(0);
it.insert_next(1);
}
check_links(&m);
assert_eq!(m.len(), 3 + len * 2);
assert_eq!(m.move_iter().collect::<~[int]>(), ~[-2,0,1,2,3,4,5,6,7,8,9,0,1]);
}
#[test]
fn test_merge() {
let mut m = list_from([0, 1, 3, 5, 6, 7, 2]);
let n = list_from([-1, 0, 0, 7, 7, 9]);
let len = m.len() + n.len();
m.merge(n, |a, b| a <= b);
assert_eq!(m.len(), len);
check_links(&m);
let res = m.move_iter().collect::<~[int]>();
assert_eq!(res, ~[-1, 0, 0, 0, 1, 3, 5, 6, 7, 2, 7, 7, 9]);
}
#[test]
fn test_insert_ordered() {
let mut n = DList::new();
n.insert_ordered(1);
assert_eq!(n.len(), 1);
assert_eq!(n.pop_front(), Some(1));
let mut m = DList::new();
m.push_back(2);
m.push_back(4);
m.insert_ordered(3);
check_links(&m);
assert_eq!(~[2,3,4], m.move_iter().collect::<~[int]>());
}
#[test]
fn test_mut_rev_iter() {
let mut m = generate_test();
for (i, elt) in m.mut_rev_iter().enumerate() {
assert_eq!((6-i) as int, *elt);
}
let mut n = DList::new();
assert!(n.mut_rev_iter().next().is_none());
n.push_front(4);
let mut it = n.mut_rev_iter();
assert!(it.next().is_some());
assert!(it.next().is_none());
}
#[test]
fn test_send() {
let n = list_from([1,2,3]);
spawn(proc() {
check_links(&n);
assert_eq!(~[&1,&2,&3], n.iter().collect::<~[&int]>());
});
}
#[test]
fn test_eq() {
let mut n: DList<u8> = list_from([]);
let mut m = list_from([]);
assert_eq!(&n, &m);
n.push_front(1);
assert!(n != m);
m.push_back(1);
assert_eq!(&n, &m);
let n = list_from([2,3,4]);
let m = list_from([1,2,3]);
assert!(n != m);
}
#[test]
fn test_ord() {
let n: DList<int> = list_from([]);
let m = list_from([1,2,3]);
assert!(n < m);
assert!(m > n);
assert!(n <= n);
assert!(n >= n);
}
#[test]
fn test_ord_nan() {
let nan = 0.0/0.0;
let n = list_from([nan]);
let m = list_from([nan]);
assert!(!(n < m));
assert!(!(n > m));
assert!(!(n <= m));
assert!(!(n >= m));
let n = list_from([nan]);
let one = list_from([1.0]);
assert!(!(n < one));
assert!(!(n > one));
assert!(!(n <= one));
assert!(!(n >= one));
let u = list_from([1.0,2.0,nan]);
let v = list_from([1.0,2.0,3.0]);
assert!(!(u < v));
assert!(!(u > v));
assert!(!(u <= v));
assert!(!(u >= v));
let s = list_from([1.0,2.0,4.0,2.0]);
let t = list_from([1.0,2.0,3.0,2.0]);
assert!(!(s < t));
assert!(s > one);
assert!(!(s <= one));
assert!(s >= one);
}
#[test]
fn test_fuzz() {
for _ in range(0, 25) {
fuzz_test(3);
fuzz_test(16);
fuzz_test(189);
}
}
#[cfg(test)]
fn fuzz_test(sz: int) {
let mut m: DList<int> = DList::new();
let mut v = ~[];
for i in range(0, sz) {
check_links(&m);
let r: u8 = rand::random();
match r % 6 {
0 => {
m.pop_back();
v.pop();
}
1 => {
m.pop_front();
v.shift();
}
2 | 4 => {
m.push_front(-i);
v.unshift(-i);
}
3 | 5 | _ => {
m.push_back(i);
v.push(i);
}
}
}
check_links(&m);
let mut i = 0u;
for (a, &b) in m.move_iter().zip(v.iter()) {
i += 1;
assert_eq!(a, b);
}
assert_eq!(i, v.len());
}
#[bench]
fn bench_collect_into(b: &mut test::BenchHarness) {
let v = &[0, ..64];
b.iter(|| {
let _: DList<int> = v.iter().map(|x| *x).collect();
})
}
#[bench]
fn bench_push_front(b: &mut test::BenchHarness) {
let mut m: DList<int> = DList::new();
b.iter(|| {
m.push_front(0);
})
}
#[bench]
fn bench_push_back(b: &mut test::BenchHarness) {
let mut m: DList<int> = DList::new();
b.iter(|| {
m.push_back(0);
})
}
#[bench]
fn bench_push_back_pop_back(b: &mut test::BenchHarness) {
let mut m: DList<int> = DList::new();
b.iter(|| {
m.push_back(0);
m.pop_back();
})
}
#[bench]
fn bench_push_front_pop_front(b: &mut test::BenchHarness) {
let mut m: DList<int> = DList::new();
b.iter(|| {
m.push_front(0);
m.pop_front();
})
}
#[bench]
fn bench_rotate_forward(b: &mut test::BenchHarness) {
let mut m: DList<int> = DList::new();
m.push_front(0);
m.push_front(1);
b.iter(|| {
m.rotate_forward();
})
}
#[bench]
fn bench_rotate_backward(b: &mut test::BenchHarness) {
let mut m: DList<int> = DList::new();
m.push_front(0);
m.push_front(1);
b.iter(|| {
m.rotate_backward();
})
}
#[bench]
fn bench_iter(b: &mut test::BenchHarness) {
let v = &[0, ..128];
let m: DList<int> = v.iter().map(|&x|x).collect();
b.iter(|| {
assert!(m.iter().len() == 128);
})
}
#[bench]
fn bench_iter_mut(b: &mut test::BenchHarness) {
let v = &[0, ..128];
let mut m: DList<int> = v.iter().map(|&x|x).collect();
b.iter(|| {
assert!(m.mut_iter().len() == 128);
})
}
#[bench]
fn bench_iter_rev(b: &mut test::BenchHarness) {
let v = &[0, ..128];
let m: DList<int> = v.iter().map(|&x|x).collect();
b.iter(|| {
assert!(m.rev_iter().len() == 128);
})
}
#[bench]
fn bench_iter_mut_rev(b: &mut test::BenchHarness) {
let v = &[0, ..128];
let mut m: DList<int> = v.iter().map(|&x|x).collect();
b.iter(|| {
assert!(m.mut_rev_iter().len() == 128);
})
}
}