/
treemap.rs
1420 lines (1218 loc) · 40.3 KB
/
treemap.rs
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// Copyright 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.
//! An ordered map and set implemented as self-balancing binary search
//! trees. The only requirement for the types is that the key implements
//! `TotalOrd`.
use std::num;
use std::util::{swap, replace};
use std::iterator::FromIterator;
// This is implemented as an AA tree, which is a simplified variation of
// a red-black tree where red (horizontal) nodes can only be added
// as a right child. The time complexity is the same, and re-balancing
// operations are more frequent but also cheaper.
// Future improvements:
// range search - O(log n) retrieval of an iterator from some key
// (possibly) implement the overloads Python does for sets:
// * intersection: &
// * difference: -
// * symmetric difference: ^
// * union: |
// These would be convenient since the methods work like `each`
#[allow(missing_doc)]
#[deriving(Clone)]
pub struct TreeMap<K, V> {
priv root: Option<~TreeNode<K, V>>,
priv length: uint
}
impl<K: Eq + TotalOrd, V: Eq> Eq for TreeMap<K, V> {
fn eq(&self, other: &TreeMap<K, V>) -> bool {
if self.len() != other.len() {
false
} else {
let mut x = self.iter();
let mut y = other.iter();
for self.len().times {
if x.next().unwrap() != y.next().unwrap() {
return false
}
}
true
}
}
fn ne(&self, other: &TreeMap<K, V>) -> bool { !self.eq(other) }
}
// Lexicographical comparison
fn lt<K: Ord + TotalOrd, V: Ord>(a: &TreeMap<K, V>,
b: &TreeMap<K, V>) -> bool {
let mut x = a.iter();
let mut y = b.iter();
let (a_len, b_len) = (a.len(), b.len());
for num::min(a_len, b_len).times {
let (key_a, value_a) = x.next().unwrap();
let (key_b, value_b) = y.next().unwrap();
if *key_a < *key_b { return true; }
if *key_a > *key_b { return false; }
if *value_a < *value_b { return true; }
if *value_a > *value_b { return false; }
}
a_len < b_len
}
impl<K: Ord + TotalOrd, V: Ord> Ord for TreeMap<K, V> {
#[inline]
fn lt(&self, other: &TreeMap<K, V>) -> bool { lt(self, other) }
#[inline]
fn le(&self, other: &TreeMap<K, V>) -> bool { !lt(other, self) }
#[inline]
fn ge(&self, other: &TreeMap<K, V>) -> bool { !lt(self, other) }
#[inline]
fn gt(&self, other: &TreeMap<K, V>) -> bool { lt(other, self) }
}
impl<K: TotalOrd, V> Container for TreeMap<K, V> {
/// Return the number of elements in the map
fn len(&self) -> uint { self.length }
/// Return true if the map contains no elements
fn is_empty(&self) -> bool { self.root.is_none() }
}
impl<K: TotalOrd, V> Mutable for TreeMap<K, V> {
/// Clear the map, removing all key-value pairs.
fn clear(&mut self) {
self.root = None;
self.length = 0
}
}
impl<K: TotalOrd, V> Map<K, V> for TreeMap<K, V> {
/// Return true if the map contains a value for the specified key
fn contains_key(&self, key: &K) -> bool {
self.find(key).is_some()
}
/// Return a reference to the value corresponding to the key
fn find<'a>(&'a self, key: &K) -> Option<&'a V> {
let mut current: &'a Option<~TreeNode<K, V>> = &self.root;
loop {
match *current {
Some(ref r) => {
match key.cmp(&r.key) {
Less => current = &r.left,
Greater => current = &r.right,
Equal => return Some(&r.value)
}
}
None => return None
}
}
}
}
impl<K: TotalOrd, V> MutableMap<K, V> for TreeMap<K, V> {
/// Return a mutable reference to the value corresponding to the key
#[inline]
fn find_mut<'a>(&'a mut self, key: &K) -> Option<&'a mut V> {
find_mut(&mut self.root, key)
}
/// Insert a key-value pair into the map. An existing value for a
/// key is replaced by the new value. Return true if the key did
/// not already exist in the map.
fn insert(&mut self, key: K, value: V) -> bool {
self.swap(key, value).is_none()
}
/// Remove a key-value pair from the map. Return true if the key
/// was present in the map, otherwise false.
fn remove(&mut self, key: &K) -> bool {
self.pop(key).is_some()
}
/// Insert a key-value pair from the map. If the key already had a value
/// present in the map, that value is returned. Otherwise None is returned.
fn swap(&mut self, key: K, value: V) -> Option<V> {
let ret = insert(&mut self.root, key, value);
if ret.is_none() { self.length += 1 }
ret
}
/// Removes a key from the map, returning the value at the key if the key
/// was previously in the map.
fn pop(&mut self, key: &K) -> Option<V> {
let ret = remove(&mut self.root, key);
if ret.is_some() { self.length -= 1 }
ret
}
}
impl<K: TotalOrd, V> TreeMap<K, V> {
/// Create an empty TreeMap
pub fn new() -> TreeMap<K, V> { TreeMap{root: None, length: 0} }
/// Visit all keys in order
pub fn each_key(&self, f: &fn(&K) -> bool) -> bool {
self.iter().advance(|(k, _)| f(k))
}
/// Visit all values in order
pub fn each_value<'a>(&'a self, f: &fn(&'a V) -> bool) -> bool {
self.iter().advance(|(_, v)| f(v))
}
/// Iterate over the map and mutate the contained values
pub fn mutate_values(&mut self, f: &fn(&K, &mut V) -> bool) -> bool {
mutate_values(&mut self.root, f)
}
/// Visit all key-value pairs in reverse order
pub fn each_reverse<'a>(&'a self, f: &fn(&'a K, &'a V) -> bool) -> bool {
each_reverse(&self.root, f)
}
/// Visit all keys in reverse order
pub fn each_key_reverse(&self, f: &fn(&K) -> bool) -> bool {
self.each_reverse(|k, _| f(k))
}
/// Visit all values in reverse order
pub fn each_value_reverse(&self, f: &fn(&V) -> bool) -> bool {
self.each_reverse(|_, v| f(v))
}
/// Get a lazy iterator over the key-value pairs in the map.
/// Requires that it be frozen (immutable).
pub fn iter<'a>(&'a self) -> TreeMapIterator<'a, K, V> {
TreeMapIterator{stack: ~[], node: &self.root, remaining: self.length}
}
/// Get a lazy iterator that consumes the treemap.
pub fn consume_iter(self) -> TreeMapConsumeIterator<K, V> {
let TreeMap { root: root, length: length } = self;
let stk = match root {
None => ~[],
Some(~tn) => ~[tn]
};
TreeMapConsumeIterator {
stack: stk,
remaining: length
}
}
}
/// Lazy forward iterator over a map
pub struct TreeMapIterator<'self, K, V> {
priv stack: ~[&'self ~TreeNode<K, V>],
priv node: &'self Option<~TreeNode<K, V>>,
priv remaining: uint
}
impl<'self, K, V> Iterator<(&'self K, &'self V)> for TreeMapIterator<'self, K, V> {
/// Advance the iterator to the next node (in order) and return a
/// tuple with a reference to the key and value. If there are no
/// more nodes, return `None`.
fn next(&mut self) -> Option<(&'self K, &'self V)> {
while !self.stack.is_empty() || self.node.is_some() {
match *self.node {
Some(ref x) => {
self.stack.push(x);
self.node = &x.left;
}
None => {
let res = self.stack.pop();
self.node = &res.right;
self.remaining -= 1;
return Some((&res.key, &res.value));
}
}
}
None
}
#[inline]
fn size_hint(&self) -> (uint, Option<uint>) {
(self.remaining, Some(self.remaining))
}
}
/// Lazy forward iterator over a map that consumes the map while iterating
pub struct TreeMapConsumeIterator<K, V> {
priv stack: ~[TreeNode<K, V>],
priv remaining: uint
}
impl<K, V> Iterator<(K, V)> for TreeMapConsumeIterator<K,V> {
#[inline]
fn next(&mut self) -> Option<(K, V)> {
while !self.stack.is_empty() {
let TreeNode {
key: key,
value: value,
left: left,
right: right,
level: level
} = self.stack.pop();
match left {
Some(~left) => {
let n = TreeNode {
key: key,
value: value,
left: None,
right: right,
level: level
};
self.stack.push(n);
self.stack.push(left);
}
None => {
match right {
Some(~right) => self.stack.push(right),
None => ()
}
self.remaining -= 1;
return Some((key, value))
}
}
}
None
}
#[inline]
fn size_hint(&self) -> (uint, Option<uint>) {
(self.remaining, Some(self.remaining))
}
}
impl<'self, T> Iterator<&'self T> for TreeSetIterator<'self, T> {
/// Advance the iterator to the next node (in order). If there are no more nodes, return `None`.
#[inline]
fn next(&mut self) -> Option<&'self T> {
do self.iter.next().map |&(value, _)| { value }
}
}
/// A implementation of the `Set` trait on top of the `TreeMap` container. The
/// only requirement is that the type of the elements contained ascribes to the
/// `TotalOrd` trait.
pub struct TreeSet<T> {
priv map: TreeMap<T, ()>
}
impl<T: Eq + TotalOrd> Eq for TreeSet<T> {
#[inline]
fn eq(&self, other: &TreeSet<T>) -> bool { self.map == other.map }
#[inline]
fn ne(&self, other: &TreeSet<T>) -> bool { self.map != other.map }
}
impl<T: Ord + TotalOrd> Ord for TreeSet<T> {
#[inline]
fn lt(&self, other: &TreeSet<T>) -> bool { self.map < other.map }
#[inline]
fn le(&self, other: &TreeSet<T>) -> bool { self.map <= other.map }
#[inline]
fn ge(&self, other: &TreeSet<T>) -> bool { self.map >= other.map }
#[inline]
fn gt(&self, other: &TreeSet<T>) -> bool { self.map > other.map }
}
impl<T: TotalOrd> Container for TreeSet<T> {
/// Return the number of elements in the set
#[inline]
fn len(&self) -> uint { self.map.len() }
/// Return true if the set contains no elements
#[inline]
fn is_empty(&self) -> bool { self.map.is_empty() }
}
impl<T: TotalOrd> Mutable for TreeSet<T> {
/// Clear the set, removing all values.
#[inline]
fn clear(&mut self) { self.map.clear() }
}
impl<T: TotalOrd> Set<T> for TreeSet<T> {
/// Return true if the set contains a value
#[inline]
fn contains(&self, value: &T) -> bool {
self.map.contains_key(value)
}
/// Return true if the set has no elements in common with `other`.
/// This is equivalent to checking for an empty intersection.
fn is_disjoint(&self, other: &TreeSet<T>) -> bool {
let mut x = self.iter();
let mut y = other.iter();
let mut a = x.next();
let mut b = y.next();
while a.is_some() && b.is_some() {
let a1 = a.unwrap();
let b1 = b.unwrap();
match a1.cmp(b1) {
Less => a = x.next(),
Greater => b = y.next(),
Equal => return false
}
}
true
}
/// Return true if the set is a subset of another
#[inline]
fn is_subset(&self, other: &TreeSet<T>) -> bool {
other.is_superset(self)
}
/// Return true if the set is a superset of another
fn is_superset(&self, other: &TreeSet<T>) -> bool {
let mut x = self.iter();
let mut y = other.iter();
let mut a = x.next();
let mut b = y.next();
while b.is_some() {
if a.is_none() {
return false
}
let a1 = a.unwrap();
let b1 = b.unwrap();
match a1.cmp(b1) {
Less => (),
Greater => return false,
Equal => b = y.next(),
}
a = x.next();
}
true
}
/// Visit the values (in-order) representing the difference
fn difference(&self, other: &TreeSet<T>, f: &fn(&T) -> bool) -> bool {
let mut x = self.iter();
let mut y = other.iter();
let mut a = x.next();
let mut b = y.next();
while a.is_some() {
if b.is_none() {
return f(a.unwrap()) && x.advance(f);
}
let a1 = a.unwrap();
let b1 = b.unwrap();
let cmp = a1.cmp(b1);
if cmp == Less {
if !f(a1) { return false; }
a = x.next();
} else {
if cmp == Equal { a = x.next() }
b = y.next();
}
}
return true;
}
/// Visit the values (in-order) representing the symmetric difference
fn symmetric_difference(&self, other: &TreeSet<T>,
f: &fn(&T) -> bool) -> bool {
let mut x = self.iter();
let mut y = other.iter();
let mut a = x.next();
let mut b = y.next();
while a.is_some() {
if b.is_none() {
return f(a.unwrap()) && x.advance(f);
}
let a1 = a.unwrap();
let b1 = b.unwrap();
let cmp = a1.cmp(b1);
if cmp == Less {
if !f(a1) { return false; }
a = x.next();
} else {
if cmp == Greater {
if !f(b1) { return false; }
} else {
a = x.next();
}
b = y.next();
}
}
b.iter().advance(|&x| f(x)) && y.advance(f)
}
/// Visit the values (in-order) representing the intersection
fn intersection(&self, other: &TreeSet<T>, f: &fn(&T) -> bool) -> bool {
let mut x = self.iter();
let mut y = other.iter();
let mut a = x.next();
let mut b = y.next();
while a.is_some() && b.is_some() {
let a1 = a.unwrap();
let b1 = b.unwrap();
let cmp = a1.cmp(b1);
if cmp == Less {
a = x.next();
} else {
if cmp == Equal {
if !f(a1) { return false }
}
b = y.next();
}
}
return true;
}
/// Visit the values (in-order) representing the union
fn union(&self, other: &TreeSet<T>, f: &fn(&T) -> bool) -> bool {
let mut x = self.iter();
let mut y = other.iter();
let mut a = x.next();
let mut b = y.next();
while a.is_some() {
if b.is_none() {
return f(a.unwrap()) && x.advance(f);
}
let a1 = a.unwrap();
let b1 = b.unwrap();
let cmp = a1.cmp(b1);
if cmp == Greater {
if !f(b1) { return false; }
b = y.next();
} else {
if !f(a1) { return false; }
if cmp == Equal {
b = y.next();
}
a = x.next();
}
}
b.iter().advance(|&x| f(x)) && y.advance(f)
}
}
impl<T: TotalOrd> MutableSet<T> for TreeSet<T> {
/// Add a value to the set. Return true if the value was not already
/// present in the set.
#[inline]
fn insert(&mut self, value: T) -> bool { self.map.insert(value, ()) }
/// Remove a value from the set. Return true if the value was
/// present in the set.
#[inline]
fn remove(&mut self, value: &T) -> bool { self.map.remove(value) }
}
impl<T: TotalOrd> TreeSet<T> {
/// Create an empty TreeSet
#[inline]
pub fn new() -> TreeSet<T> { TreeSet{map: TreeMap::new()} }
/// Get a lazy iterator over the values in the set.
/// Requires that it be frozen (immutable).
#[inline]
pub fn iter<'a>(&'a self) -> TreeSetIterator<'a, T> {
TreeSetIterator{iter: self.map.iter()}
}
/// Visit all values in reverse order
#[inline]
pub fn each_reverse(&self, f: &fn(&T) -> bool) -> bool {
self.map.each_key_reverse(f)
}
}
/// Lazy forward iterator over a set
pub struct TreeSetIterator<'self, T> {
priv iter: TreeMapIterator<'self, T, ()>
}
// Nodes keep track of their level in the tree, starting at 1 in the
// leaves and with a red child sharing the level of the parent.
#[deriving(Clone)]
struct TreeNode<K, V> {
key: K,
value: V,
left: Option<~TreeNode<K, V>>,
right: Option<~TreeNode<K, V>>,
level: uint
}
impl<K: TotalOrd, V> TreeNode<K, V> {
/// Creates a new tree node.
#[inline]
pub fn new(key: K, value: V) -> TreeNode<K, V> {
TreeNode{key: key, value: value, left: None, right: None, level: 1}
}
}
fn each<'r, K: TotalOrd, V>(node: &'r Option<~TreeNode<K, V>>,
f: &fn(&'r K, &'r V) -> bool) -> bool {
node.iter().advance(|x| each(&x.left, |k,v| f(k,v)) && f(&x.key, &x.value) &&
each(&x.right, |k,v| f(k,v)))
}
fn each_reverse<'r, K: TotalOrd, V>(node: &'r Option<~TreeNode<K, V>>,
f: &fn(&'r K, &'r V) -> bool) -> bool {
node.iter().advance(|x| each_reverse(&x.right, |k,v| f(k,v)) && f(&x.key, &x.value) &&
each_reverse(&x.left, |k,v| f(k,v)))
}
fn mutate_values<'r, K: TotalOrd, V>(node: &'r mut Option<~TreeNode<K, V>>,
f: &fn(&'r K, &'r mut V) -> bool)
-> bool {
match *node {
Some(~TreeNode{key: ref key, value: ref mut value, left: ref mut left,
right: ref mut right, _}) => {
if !mutate_values(left, |k,v| f(k,v)) { return false }
if !f(key, value) { return false }
if !mutate_values(right, |k,v| f(k,v)) { return false }
}
None => return false
}
true
}
// Remove left horizontal link by rotating right
fn skew<K: TotalOrd, V>(node: &mut ~TreeNode<K, V>) {
if node.left.map_default(false, |x| x.level == node.level) {
let mut save = node.left.take_unwrap();
swap(&mut node.left, &mut save.right); // save.right now None
swap(node, &mut save);
node.right = Some(save);
}
}
// Remove dual horizontal link by rotating left and increasing level of
// the parent
fn split<K: TotalOrd, V>(node: &mut ~TreeNode<K, V>) {
if node.right.map_default(false,
|x| x.right.map_default(false, |y| y.level == node.level)) {
let mut save = node.right.take_unwrap();
swap(&mut node.right, &mut save.left); // save.left now None
save.level += 1;
swap(node, &mut save);
node.left = Some(save);
}
}
fn find_mut<'r, K: TotalOrd, V>(node: &'r mut Option<~TreeNode<K, V>>,
key: &K)
-> Option<&'r mut V> {
match *node {
Some(ref mut x) => {
match key.cmp(&x.key) {
Less => find_mut(&mut x.left, key),
Greater => find_mut(&mut x.right, key),
Equal => Some(&mut x.value),
}
}
None => None
}
}
fn insert<K: TotalOrd, V>(node: &mut Option<~TreeNode<K, V>>,
key: K, value: V) -> Option<V> {
match *node {
Some(ref mut save) => {
match key.cmp(&save.key) {
Less => {
let inserted = insert(&mut save.left, key, value);
skew(save);
split(save);
inserted
}
Greater => {
let inserted = insert(&mut save.right, key, value);
skew(save);
split(save);
inserted
}
Equal => {
save.key = key;
Some(replace(&mut save.value, value))
}
}
}
None => {
*node = Some(~TreeNode::new(key, value));
None
}
}
}
fn remove<K: TotalOrd, V>(node: &mut Option<~TreeNode<K, V>>,
key: &K) -> Option<V> {
fn heir_swap<K: TotalOrd, V>(node: &mut ~TreeNode<K, V>,
child: &mut Option<~TreeNode<K, V>>) {
// *could* be done without recursion, but it won't borrow check
for child.mut_iter().advance |x| {
if x.right.is_some() {
heir_swap(node, &mut x.right);
} else {
swap(&mut node.key, &mut x.key);
swap(&mut node.value, &mut x.value);
}
}
}
match *node {
None => {
return None; // bottom of tree
}
Some(ref mut save) => {
let (ret, rebalance) = match key.cmp(&save.key) {
Less => (remove(&mut save.left, key), true),
Greater => (remove(&mut save.right, key), true),
Equal => {
if save.left.is_some() {
if save.right.is_some() {
let mut left = save.left.take_unwrap();
if left.right.is_some() {
heir_swap(save, &mut left.right);
} else {
swap(&mut save.key, &mut left.key);
swap(&mut save.value, &mut left.value);
}
save.left = Some(left);
(remove(&mut save.left, key), true)
} else {
let new = save.left.take_unwrap();
let ~TreeNode{value, _} = replace(save, new);
*save = save.left.take_unwrap();
(Some(value), true)
}
} else if save.right.is_some() {
let new = save.right.take_unwrap();
let ~TreeNode{value, _} = replace(save, new);
(Some(value), true)
} else {
(None, false)
}
}
};
if rebalance {
let left_level = save.left.map_default(0, |x| x.level);
let right_level = save.right.map_default(0, |x| x.level);
// re-balance, if necessary
if left_level < save.level - 1 || right_level < save.level - 1 {
save.level -= 1;
if right_level > save.level {
for save.right.mut_iter().advance |x| { x.level = save.level }
}
skew(save);
for save.right.mut_iter().advance |right| {
skew(right);
for right.right.mut_iter().advance |x| { skew(x) }
}
split(save);
for save.right.mut_iter().advance |x| { split(x) }
}
return ret;
}
}
}
return match node.take() {
Some(~TreeNode{value, _}) => Some(value), None => fail!()
};
}
impl<K: TotalOrd, V, T: Iterator<(K, V)>> FromIterator<(K, V), T> for TreeMap<K, V> {
pub fn from_iterator(iter: &mut T) -> TreeMap<K, V> {
let mut map = TreeMap::new();
for iter.advance |(k, v)| {
map.insert(k, v);
}
map
}
}
impl<T: TotalOrd, Iter: Iterator<T>> FromIterator<T, Iter> for TreeSet<T> {
pub fn from_iterator(iter: &mut Iter) -> TreeSet<T> {
let mut set = TreeSet::new();
for iter.advance |elem| {
set.insert(elem);
}
set
}
}
#[cfg(test)]
mod test_treemap {
use super::*;
use std::rand::RngUtil;
use std::rand;
#[test]
fn find_empty() {
let m = TreeMap::new::<int, int>(); assert!(m.find(&5) == None);
}
#[test]
fn find_not_found() {
let mut m = TreeMap::new();
assert!(m.insert(1, 2));
assert!(m.insert(5, 3));
assert!(m.insert(9, 3));
assert_eq!(m.find(&2), None);
}
#[test]
fn test_find_mut() {
let mut m = TreeMap::new();
assert!(m.insert(1, 12));
assert!(m.insert(2, 8));
assert!(m.insert(5, 14));
let new = 100;
match m.find_mut(&5) {
None => fail!(), Some(x) => *x = new
}
assert_eq!(m.find(&5), Some(&new));
}
#[test]
fn insert_replace() {
let mut m = TreeMap::new();
assert!(m.insert(5, 2));
assert!(m.insert(2, 9));
assert!(!m.insert(2, 11));
assert_eq!(m.find(&2).unwrap(), &11);
}
#[test]
fn test_clear() {
let mut m = TreeMap::new();
m.clear();
assert!(m.insert(5, 11));
assert!(m.insert(12, -3));
assert!(m.insert(19, 2));
m.clear();
assert!(m.find(&5).is_none());
assert!(m.find(&12).is_none());
assert!(m.find(&19).is_none());
assert!(m.is_empty());
}
#[test]
fn u8_map() {
let mut m = TreeMap::new();
let k1 = "foo".as_bytes();
let k2 = "bar".as_bytes();
let v1 = "baz".as_bytes();
let v2 = "foobar".as_bytes();
m.insert(k1.clone(), v1.clone());
m.insert(k2.clone(), v2.clone());
assert_eq!(m.find(&k2), Some(&v2));
assert_eq!(m.find(&k1), Some(&v1));
}
fn check_equal<K: Eq + TotalOrd, V: Eq>(ctrl: &[(K, V)],
map: &TreeMap<K, V>) {
assert_eq!(ctrl.is_empty(), map.is_empty());
for ctrl.iter().advance |x| {
let &(ref k, ref v) = x;
assert!(map.find(k).unwrap() == v)
}
for map.iter().advance |(map_k, map_v)| {
let mut found = false;
for ctrl.iter().advance |x| {
let &(ref ctrl_k, ref ctrl_v) = x;
if *map_k == *ctrl_k {
assert!(*map_v == *ctrl_v);
found = true;
break;
}
}
assert!(found);
}
}
fn check_left<K: TotalOrd, V>(node: &Option<~TreeNode<K, V>>,
parent: &~TreeNode<K, V>) {
match *node {
Some(ref r) => {
assert_eq!(r.key.cmp(&parent.key), Less);
assert!(r.level == parent.level - 1); // left is black
check_left(&r.left, r);
check_right(&r.right, r, false);
}
None => assert!(parent.level == 1) // parent is leaf
}
}
fn check_right<K: TotalOrd, V>(node: &Option<~TreeNode<K, V>>,
parent: &~TreeNode<K, V>,
parent_red: bool) {
match *node {
Some(ref r) => {
assert_eq!(r.key.cmp(&parent.key), Greater);
let red = r.level == parent.level;
if parent_red { assert!(!red) } // no dual horizontal links
// Right red or black
assert!(red || r.level == parent.level - 1);
check_left(&r.left, r);
check_right(&r.right, r, red);
}
None => assert!(parent.level == 1) // parent is leaf
}
}
fn check_structure<K: TotalOrd, V>(map: &TreeMap<K, V>) {
match map.root {
Some(ref r) => {
check_left(&r.left, r);
check_right(&r.right, r, false);
}
None => ()
}
}
#[test]
fn test_rand_int() {
let mut map = TreeMap::new::<int, int>();
let mut ctrl = ~[];
check_equal(ctrl, &map);
assert!(map.find(&5).is_none());
let mut rng = rand::IsaacRng::new_seeded(&[42]);
for 3.times {
for 90.times {
let k = rng.gen();
let v = rng.gen();
if !ctrl.iter().any(|x| x == &(k, v)) {
assert!(map.insert(k, v));
ctrl.push((k, v));
check_structure(&map);
check_equal(ctrl, &map);
}
}
for 30.times {
let r = rng.gen_uint_range(0, ctrl.len());
let (key, _) = ctrl.remove(r);
assert!(map.remove(&key));
check_structure(&map);
check_equal(ctrl, &map);
}
}
}
#[test]
fn test_len() {
let mut m = TreeMap::new();
assert!(m.insert(3, 6));
assert_eq!(m.len(), 1);
assert!(m.insert(0, 0));
assert_eq!(m.len(), 2);
assert!(m.insert(4, 8));
assert_eq!(m.len(), 3);
assert!(m.remove(&3));
assert_eq!(m.len(), 2);
assert!(!m.remove(&5));
assert_eq!(m.len(), 2);
assert!(m.insert(2, 4));
assert_eq!(m.len(), 3);
assert!(m.insert(1, 2));
assert_eq!(m.len(), 4);
}
#[test]
fn test_iterator() {
let mut m = TreeMap::new();
assert!(m.insert(3, 6));
assert!(m.insert(0, 0));
assert!(m.insert(4, 8));
assert!(m.insert(2, 4));
assert!(m.insert(1, 2));
let mut n = 0;
for m.iter().advance |(k, v)| {
assert_eq!(*k, n);
assert_eq!(*v, n * 2);
n += 1;
}
}
#[test]
fn test_each_reverse() {
let mut m = TreeMap::new();
assert!(m.insert(3, 6));