// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this
// file, You can obtain one at http://mozilla.org/MPL/2.0/.
//! A persistent vector.
//!
//! This is a sequence of elements in insertion order - if you need a
//! list of things, any kind of list of things, this is what you're
//! looking for.
//!
//! It's implemented as an [RRB vector][rrbpaper] with [smart
//! head/tail chunking][chunkedseq]. In performance terms, this means
//! that practically every operation is O(log n), except push/pop on
//! both sides, which will be O(1) amortised, and O(log n) in the
//! worst case. In practice, the push/pop operations will be
//! blindingly fast, nearly on par with the native
//! [`VecDeque`][VecDeque], and other operations will have decent, if
//! not high, performance, but they all have more or less the same
//! O(log n) complexity, so you don't need to keep their performance
//! characteristics in mind - everything, even splitting and merging,
//! is safe to use and never too slow.
//!
//! ## Performance Notes
//!
//! Because of the head/tail chunking technique, until you push a
//! number of items above double the tree's branching factor (that's
//! `self.len()` = 2 × *k* (where *k* = 64) = 128) on either side, the
//! data structure is still just a handful of arrays, not yet an RRB
//! tree, so you'll see performance and memory characteristics similar
//! to [`Vec`][Vec] or [`VecDeque`][VecDeque].
//!
//! This means that the structure always preallocates four chunks of
//! size *k* (*k* being the tree's branching factor), equivalent to a
//! [`Vec`][Vec] with an initial capacity of 256. Beyond that, it will
//! allocate tree nodes of capacity *k* as needed.
//!
//! [rrbpaper]: https://infoscience.epfl.ch/record/213452/files/rrbvector.pdf
//! [chunkedseq]: http://deepsea.inria.fr/pasl/chunkedseq.pdf
//! [Vec]: https://doc.rust-lang.org/std/vec/struct.Vec.html
//! [VecDeque]: https://doc.rust-lang.org/std/collections/struct.VecDeque.html
use std::borrow::Borrow;
use std::cmp::Ordering;
use std::fmt::{Debug, Error, Formatter};
use std::hash::{Hash, Hasher};
use std::iter::Sum;
use std::iter::{Chain, FromIterator, FusedIterator};
use std::mem::{replace, swap};
use std::ops::{Add, Index, IndexMut};
#[cfg(has_range_bound)]
use std::ops::{Bound, RangeBounds};
use nodes::chunk::{
Chunk, ConsumingIter as ConsumingChunkIter, Iter as ChunkIter, IterMut as ChunkIterMut,
CHUNK_SIZE,
};
use nodes::rrb::{
ConsumingIter as ConsumingNodeIter, Iter as NodeIter, IterMut as NodeIterMut, Node, PopResult,
PushResult, SplitResult,
};
use sort;
use util::{clone_ref, swap_indices, Ref, Side};
/// Construct a vector from a sequence of elements.
///
/// # Examples
///
/// ```
/// # #[macro_use] extern crate im;
/// # use im::vector::Vector;
/// # fn main() {
/// assert_eq!(
/// vector![1, 2, 3],
/// Vector::from(vec![1, 2, 3])
/// );
/// # }
/// ```
#[macro_export]
macro_rules! vector {
() => { $crate::vector::Vector::new() };
( $($x:expr),* ) => {{
let mut l = $crate::vector::Vector::new();
$(
l.push_back($x);
)*
l
}};
( $($x:expr ,)* ) => {{
let mut l = $crate::vector::Vector::new();
$(
l.push_back($x);
)*
l
}};
}
/// A persistent vector.
///
/// This is a sequence of elements in insertion order - if you need a
/// list of things, any kind of list of things, this is what you're
/// looking for.
///
/// It's implemented as an [RRB vector][rrbpaper] with [smart
/// head/tail chunking][chunkedseq]. In performance terms, this means
/// that practically every operation is O(log n), except push/pop on
/// both sides, which will be O(1) amortised, and O(log n) in the
/// worst case. In practice, the push/pop operations will be
/// blindingly fast, nearly on par with the native
/// [`VecDeque`][VecDeque], and other operations will have decent, if
/// not high, performance, but they all have more or less the same
/// O(log n) complexity, so you don't need to keep their performance
/// characteristics in mind - everything, even splitting and merging,
/// is safe to use and never too slow.
///
/// ## Performance Notes
///
/// Because of the head/tail chunking technique, until you push a
/// number of items above double the tree's branching factor (that's
/// `self.len()` = 2 × *k* (where *k* = 64) = 128) on either side, the
/// data structure is still just a handful of arrays, not yet an RRB
/// tree, so you'll see performance and memory characteristics similar
/// to [`Vec`][Vec] or [`VecDeque`][VecDeque].
///
/// This means that the structure always preallocates four chunks of
/// size *k* (*k* being the tree's branching factor), equivalent to a
/// [`Vec`][Vec] with an initial capacity of 256. Beyond that, it will
/// allocate tree nodes of capacity *k* as needed.
///
/// [rrbpaper]: https://infoscience.epfl.ch/record/213452/files/rrbvector.pdf
/// [chunkedseq]: http://deepsea.inria.fr/pasl/chunkedseq.pdf
/// [Vec]: https://doc.rust-lang.org/std/vec/struct.Vec.html
/// [VecDeque]: https://doc.rust-lang.org/std/collections/struct.VecDeque.html
pub struct Vector<A> {
length: usize,
middle_level: usize,
outer_f: Ref<Chunk<A>>,
inner_f: Ref<Chunk<A>>,
middle: Ref<Node<A>>,
inner_b: Ref<Chunk<A>>,
outer_b: Ref<Chunk<A>>,
}
impl<A: Clone> Vector<A> {
/// Construct an empty vector.
pub fn new() -> Self {
Vector {
length: 0,
middle_level: 0,
outer_f: Ref::new(Chunk::new()),
inner_f: Ref::new(Chunk::new()),
middle: Ref::new(Node::new()),
inner_b: Ref::new(Chunk::new()),
outer_b: Ref::new(Chunk::new()),
}
}
/// Construct a vector with a single value.
pub fn singleton(a: A) -> Self {
let mut out = Self::new();
out.push_back(a);
out
}
/// Get the length of a vector.
///
/// Time: O(1)
///
/// # Examples
///
/// ```
/// # #[macro_use] extern crate im;
/// # fn main() {
/// assert_eq!(5, vector![1, 2, 3, 4, 5].len());
/// # }
/// ```
#[inline]
pub fn len(&self) -> usize {
self.length
}
/// Test whether a vector is empty.
///
/// Time: O(1)
///
/// # Examples
///
/// ```
/// # #[macro_use] extern crate im;
/// # use im::Vector;
/// # fn main() {
/// let vec = vector!["Joe", "Mike", "Robert"];
/// assert_eq!(false, vec.is_empty());
/// assert_eq!(true, Vector::<i32>::new().is_empty());
/// # }
/// ```
#[inline]
pub fn is_empty(&self) -> bool {
self.len() == 0
}
/// Get an iterator over a vector.
///
/// Time: O(1)
#[inline]
pub fn iter(&self) -> Iter<A> {
Iter::new(self)
}
/// Get a mutable iterator over a vector.
///
/// Time: O(1)
#[inline]
pub fn iter_mut(&mut self) -> IterMut<A> {
IterMut::new(self)
}
/// Get a reference to the value at index `index` in a vector.
///
/// Returns `None` if the index is out of bounds.
///
/// Time: O(log n)
///
/// # Examples
///
/// ```
/// # #[macro_use] extern crate im;
/// # use im::Vector;
/// # fn main() {
/// let vec = vector!["Joe", "Mike", "Robert"];
/// assert_eq!(Some(&"Robert"), vec.get(2));
/// assert_eq!(None, vec.get(5));
/// # }
/// ```
pub fn get(&self, index: usize) -> Option<&A> {
if index >= self.len() {
return None;
}
let mut local_index = index;
if local_index < self.outer_f.len() {
return Some(&self.outer_f[local_index]);
}
local_index -= self.outer_f.len();
if local_index < self.inner_f.len() {
return Some(&self.inner_f[local_index]);
}
local_index -= self.inner_f.len();
if local_index < self.middle.len() {
return Some(self.middle.index(self.middle_level, local_index));
}
local_index -= self.middle.len();
if local_index < self.inner_b.len() {
return Some(&self.inner_b[local_index]);
}
local_index -= self.inner_b.len();
Some(&self.outer_b[local_index])
}
/// Get a mutable reference to the value at index `index` in a
/// vector.
///
/// Returns `None` if the index is out of bounds.
///
/// Time: O(log n)
///
/// # Examples
///
/// ```
/// # #[macro_use] extern crate im;
/// # use im::Vector;
/// # fn main() {
/// let mut vec = vector!["Joe", "Mike", "Robert"];
/// {
/// let robert = vec.get_mut(2).unwrap();
/// assert_eq!(&mut "Robert", robert);
/// *robert = "Bjarne";
/// }
/// assert_eq!(vector!["Joe", "Mike", "Bjarne"], vec);
/// # }
/// ```
pub fn get_mut(&mut self, index: usize) -> Option<&mut A> {
if index >= self.len() {
return None;
}
let mut local_index = index;
if local_index < self.outer_f.len() {
let outer_f = Ref::make_mut(&mut self.outer_f);
return Some(&mut outer_f[local_index]);
}
local_index -= self.outer_f.len();
if local_index < self.inner_f.len() {
let inner_f = Ref::make_mut(&mut self.inner_f);
return Some(&mut inner_f[local_index]);
}
local_index -= self.inner_f.len();
if local_index < self.middle.len() {
let middle = Ref::make_mut(&mut self.middle);
return Some(middle.index_mut(self.middle_level, local_index));
}
local_index -= self.middle.len();
if local_index < self.inner_b.len() {
let inner_b = Ref::make_mut(&mut self.inner_b);
return Some(&mut inner_b[local_index]);
}
local_index -= self.inner_b.len();
let outer_b = Ref::make_mut(&mut self.outer_b);
Some(&mut outer_b[local_index])
}
/// Get the first element of a vector.
///
/// If the vector is empty, `None` is returned.
///
/// Time: O(log n)
#[inline]
pub fn front(&self) -> Option<&A> {
self.get(0)
}
/// Get a mutable reference to the first element of a vector.
///
/// If the vector is empty, `None` is returned.
///
/// Time: O(log n)
#[inline]
pub fn front_mut(&mut self) -> Option<&mut A> {
self.get_mut(0)
}
/// Get the first element of a vector.
///
/// If the vector is empty, `None` is returned.
///
/// This is an alias for the [`front`][front] method.
///
/// Time: O(log n)
///
/// [front]: #method.front
#[inline]
pub fn head(&self) -> Option<&A> {
self.get(0)
}
/// Get the last element of a vector.
///
/// If the vector is empty, `None` is returned.
///
/// Time: O(log n)
pub fn back(&self) -> Option<&A> {
if self.is_empty() {
None
} else {
self.get(self.len() - 1)
}
}
/// Get a mutable reference to the last element of a vector.
///
/// If the vector is empty, `None` is returned.
///
/// Time: O(log n)
pub fn back_mut(&mut self) -> Option<&mut A> {
if self.is_empty() {
None
} else {
let len = self.len();
self.get_mut(len - 1)
}
}
/// Get the last element of a vector.
///
/// If the vector is empty, `None` is returned.
///
/// This is an alias for the [`back`][back] method.
///
/// Time: O(log n)
///
/// [back]: #method.back
#[inline]
pub fn last(&self) -> Option<&A> {
self.back()
}
/// Get the index of a given element in the vector.
///
/// Searches the vector for the first occurrence of a given value,
/// and returns the index of the value if it's there. Otherwise,
/// it returns `None`.
///
/// Time: O(n)
///
/// # Examples
///
/// ```
/// # #[macro_use] extern crate im;
/// # use im::Vector;
/// # fn main() {
/// let mut vec = vector![1, 2, 3, 4, 5];
/// assert_eq!(Some(2), vec.index_of(&3));
/// assert_eq!(None, vec.index_of(&31337));
/// # }
/// ```
pub fn index_of(&self, value: &A) -> Option<usize>
where
A: PartialEq,
{
for (index, item) in self.iter().enumerate() {
if value == item {
return Some(index);
}
}
None
}
/// Test if a given element is in the vector.
///
/// Searches the vector for the first occurrence of a given value,
/// and returns `true if it's there. If it's nowhere to be found
/// in the vector, it returns `false`.
///
/// Time: O(n)
///
/// # Examples
///
/// ```
/// # #[macro_use] extern crate im;
/// # use im::Vector;
/// # fn main() {
/// let mut vec = vector![1, 2, 3, 4, 5];
/// assert_eq!(true, vec.contains(&3));
/// assert_eq!(false, vec.contains(&31337));
/// # }
/// ```
#[inline]
pub fn contains(&self, value: &A) -> bool
where
A: PartialEq,
{
self.index_of(value).is_some()
}
/// Create a new vector with the value at index `index` updated.
///
/// Panics if the index is out of bounds.
///
/// Time: O(log n)
///
/// # Examples
///
/// ```
/// # #[macro_use] extern crate im;
/// # use im::Vector;
/// # fn main() {
/// let mut vec = vector![1, 2, 3];
/// assert_eq!(vector![1, 5, 3], vec.update(1, 5));
/// # }
/// ```
pub fn update(&self, index: usize, value: A) -> Self {
let mut out = self.clone();
out[index] = value;
out
}
/// Update the value at index `index` in a vector.
///
/// Panics if the index is out of bounds.
///
/// Time: O(log n)
#[inline]
pub fn set(&mut self, index: usize, value: A) {
self[index] = value;
}
/// Swaps the elements at indices `i` and `j`.
///
/// Time: O(log n)
pub fn swap(&mut self, i: usize, j: usize) {
swap_indices(self, i, j)
}
/// Push a value to the front of a vector.
///
/// Time: O(1)*
///
/// # Examples
///
/// ```
/// # #[macro_use] extern crate im;
/// # use im::Vector;
/// # fn main() {
/// let mut vec = vector![5, 6, 7];
/// vec.push_front(4);
/// assert_eq!(vector![4, 5, 6, 7], vec);
/// # }
/// ```
pub fn push_front(&mut self, value: A) {
if self.outer_f.is_full() {
swap(&mut self.outer_f, &mut self.inner_f);
if !self.outer_f.is_empty() {
assert!(self.outer_f.is_full());
let mut chunk = Ref::new(Chunk::new());
swap(&mut chunk, &mut self.outer_f);
self.push_middle(Side::Left, chunk);
}
}
self.length += 1;
let outer_f = Ref::make_mut(&mut self.outer_f);
outer_f.push_front(value)
}
/// Push a value to the back of a vector.
///
/// Time: O(1)*
///
/// # Examples
///
/// ```
/// # #[macro_use] extern crate im;
/// # use im::Vector;
/// # fn main() {
/// let mut vec = vector![1, 2, 3];
/// vec.push_back(4);
/// assert_eq!(vector![1, 2, 3, 4], vec);
/// # }
/// ```
pub fn push_back(&mut self, value: A) {
if self.outer_b.is_full() {
swap(&mut self.outer_b, &mut self.inner_b);
if !self.outer_b.is_empty() {
assert!(self.outer_b.is_full());
let mut chunk = Ref::new(Chunk::new());
swap(&mut chunk, &mut self.outer_b);
self.push_middle(Side::Right, chunk);
}
}
self.length += 1;
let outer_b = Ref::make_mut(&mut self.outer_b);
outer_b.push_back(value)
}
/// Remove the first element from a vector and return it.
///
/// Time: O(1)*
///
/// # Examples
///
/// ```
/// # #[macro_use] extern crate im;
/// # use im::Vector;
/// # fn main() {
/// let mut vec = vector![1, 2, 3];
/// assert_eq!(Some(1), vec.pop_front());
/// assert_eq!(vector![2, 3], vec);
/// # }
/// ```
pub fn pop_front(&mut self) -> Option<A> {
if self.is_empty() {
return None;
}
if self.outer_f.is_empty() {
if self.inner_f.is_empty() {
if self.middle.is_empty() {
if self.inner_b.is_empty() {
swap(&mut self.outer_f, &mut self.outer_b);
} else {
swap(&mut self.outer_f, &mut self.inner_b);
}
} else {
self.outer_f = self.pop_middle(Side::Left).unwrap();
}
} else {
swap(&mut self.outer_f, &mut self.inner_f);
}
}
self.length -= 1;
let outer_f = Ref::make_mut(&mut self.outer_f);
Some(outer_f.pop_front())
}
/// Remove the last element from a vector and return it.
///
/// Time: O(1)*
///
/// # Examples
///
/// ```
/// # #[macro_use] extern crate im;
/// # use im::Vector;
/// # fn main() {
/// let mut vec = vector![1, 2, 3];
/// assert_eq!(Some(3), vec.pop_back());
/// assert_eq!(vector![1, 2], vec);
/// # }
/// ```
pub fn pop_back(&mut self) -> Option<A> {
if self.is_empty() {
return None;
}
if self.outer_b.is_empty() {
if self.inner_b.is_empty() {
if self.middle.is_empty() {
if self.inner_f.is_empty() {
swap(&mut self.outer_b, &mut self.outer_f);
} else {
swap(&mut self.outer_b, &mut self.inner_f);
}
} else {
self.outer_b = self.pop_middle(Side::Right).unwrap();
}
} else {
swap(&mut self.outer_b, &mut self.inner_b);
}
}
self.length -= 1;
let outer_b = Ref::make_mut(&mut self.outer_b);
Some(outer_b.pop_back())
}
/// Append the vector `other` to the end of the current vector.
///
/// Time: O(log n)
///
/// # Examples
///
/// ```
/// # #[macro_use] extern crate im;
/// # use im::vector::Vector;
/// # fn main() {
/// let mut vec = vector![1, 2, 3];
/// vec.append(vector![7, 8, 9]);
/// assert_eq!(vector![1, 2, 3, 7, 8, 9], vec);
/// # }
/// ```
pub fn append(&mut self, mut other: Self) {
if other.is_empty() {
return;
}
if self.is_empty() {
replace(self, other);
return;
}
if self.middle.is_empty() && other.middle.is_empty() {
if self.inner_b.is_empty()
&& self.outer_b.is_empty()
&& other.inner_f.is_empty()
&& other.outer_f.is_empty()
{
self.inner_b = other.inner_b;
self.outer_b = other.outer_b;
self.length += other.length;
return;
}
if self.len() + other.len() <= CHUNK_SIZE * 4 {
while let Some(value) = other.pop_front() {
self.push_back(value);
}
return;
}
}
let inner_b1 = self.inner_b.clone();
self.push_middle(Side::Right, inner_b1);
let outer_b1 = self.outer_b.clone();
self.push_middle(Side::Right, outer_b1);
let inner_f2 = other.inner_f.clone();
other.push_middle(Side::Left, inner_f2);
let outer_f2 = other.outer_f.clone();
other.push_middle(Side::Left, outer_f2);
let mut middle1 = clone_ref(replace(&mut self.middle, Ref::from(Node::new())));
let mut middle2 = clone_ref(other.middle);
self.middle_level = if self.middle_level > other.middle_level {
middle2 = middle2.elevate(self.middle_level - other.middle_level);
self.middle_level
} else if self.middle_level < other.middle_level {
middle1 = middle1.elevate(other.middle_level - self.middle_level);
other.middle_level
} else {
self.middle_level
} + 1;
self.middle = Ref::new(Node::merge(
Ref::from(middle1),
Ref::from(middle2),
self.middle_level - 1,
));
self.inner_b = other.inner_b;
self.outer_b = other.outer_b;
self.length += other.length;
self.prune();
}
/// Retain only the elements specified by the predicate.
///
/// Remove all elements for which the provided function `f`
/// returns false from the vector.
///
/// Time: O(n)
// FIXME will actually be O(n log n) without the focus optimisation
pub fn retain<F>(&mut self, mut f: F)
where
F: FnMut(&A) -> bool,
{
let len = self.len();
let mut del = 0;
for i in 0..len {
if !f(&self[i]) {
del += 1;
} else if del > 0 {
self.swap(i - del, i);
}
}
if del > 0 {
self.split_off(len - del);
}
}
/// Split a vector at a given index.
///
/// Split a vector at a given index, consuming the vector and
/// returning a pair of the left hand side and the right hand side
/// of the split.
///
/// Time: O(log n)
///
/// # Examples
///
/// ```
/// # #[macro_use] extern crate im;
/// # use im::vector::Vector;
/// # fn main() {
/// let mut vec = vector![1, 2, 3, 7, 8, 9];
/// let (left, right) = vec.split_at(3);
/// assert_eq!(vector![1, 2, 3], left);
/// assert_eq!(vector![7, 8, 9], right);
/// # }
/// ```
pub fn split_at(mut self, index: usize) -> (Self, Self) {
let right = self.split_off(index);
(self, right)
}
/// Split a vector at a given index.
///
/// Split a vector at a given index, leaving the left hand side in
/// the current vector and returning a new vector containing the
/// right hand side.
///
/// Time: O(log n)
///
/// # Examples
///
/// ```
/// # #[macro_use] extern crate im;
/// # use im::vector::Vector;
/// # fn main() {
/// let mut left = vector![1, 2, 3, 7, 8, 9];
/// let right = left.split_off(3);
/// assert_eq!(vector![1, 2, 3], left);
/// assert_eq!(vector![7, 8, 9], right);
/// # }
/// ```
pub fn split_off(&mut self, index: usize) -> Self {
assert!(index < self.len());
let mut local_index = index;
if local_index < self.outer_f.len() {
let of2 = Ref::make_mut(&mut self.outer_f).split(local_index);
let right = Vector {
length: self.length - index,
middle_level: self.middle_level,
outer_f: Ref::new(of2),
inner_f: replace_def(&mut self.inner_f),
middle: replace_def(&mut self.middle),
inner_b: replace_def(&mut self.inner_b),
outer_b: replace_def(&mut self.outer_b),
};
self.length = index;
self.middle_level = 0;
return right;
}
local_index -= self.outer_f.len();
if local_index < self.inner_f.len() {
let if2 = Ref::make_mut(&mut self.inner_f).split(local_index);
let right = Vector {
length: self.length - index,
middle_level: self.middle_level,
outer_f: Ref::new(if2),
inner_f: Ref::<Chunk<A>>::default(),
middle: replace_def(&mut self.middle),
inner_b: replace_def(&mut self.inner_b),
outer_b: replace_def(&mut self.outer_b),
};
self.length = index;
self.middle_level = 0;
swap(&mut self.outer_b, &mut self.inner_f);
return right;
}
local_index -= self.inner_f.len();
if local_index < self.middle.len() {
let mut right_middle = self.middle.clone();
let (c1, c2) = {
let m1 = Ref::make_mut(&mut self.middle);
let m2 = Ref::make_mut(&mut right_middle);
match m1.split(self.middle_level, Side::Right, local_index) {
SplitResult::Dropped(_) => (),
SplitResult::OutOfBounds => unreachable!(),
};
match m2.split(self.middle_level, Side::Left, local_index) {
SplitResult::Dropped(_) => (),
SplitResult::OutOfBounds => unreachable!(),
};
let c1 = match m1.pop_chunk(self.middle_level, Side::Right) {
PopResult::Empty => Ref::<Chunk<A>>::default(),
PopResult::Done(chunk) => chunk,
PopResult::Drained(chunk) => {
m1.clear_node();
chunk
}
};
let c2 = match m2.pop_chunk(self.middle_level, Side::Left) {
PopResult::Empty => Ref::<Chunk<A>>::default(),
PopResult::Done(chunk) => chunk,
PopResult::Drained(chunk) => {
m2.clear_node();
chunk
}
};
(c1, c2)
};
let mut right = Vector {
length: self.length - index,
middle_level: self.middle_level,
outer_f: c2,
inner_f: Ref::<Chunk<A>>::default(),
middle: right_middle,
inner_b: replace_def(&mut self.inner_b),
outer_b: replace(&mut self.outer_b, c1),
};
self.length = index;
self.prune();
right.prune();
return right;
}
local_index -= self.middle.len();
if local_index < self.inner_b.len() {
let ib2 = Ref::make_mut(&mut self.inner_b).split(local_index);
let right = Vector {
length: self.length - index,
outer_b: replace_def(&mut self.outer_b),
outer_f: Ref::new(ib2),
..Vector::new()
};
self.length = index;
swap(&mut self.outer_b, &mut self.inner_b);
return right;
}
local_index -= self.inner_b.len();
let ob2 = Ref::make_mut(&mut self.outer_b).split(local_index);
let right = Vector {
length: self.length - index,
outer_b: Ref::new(ob2),
..Vector::new()
};
self.length = index;
right
}
/// Construct a vector with `count` elements removed from the
/// start of the current vector.
///
/// Time: O(log n)
pub fn skip(&self, count: usize) -> Self {
// FIXME can be made more efficient by dropping the unwanted side without constructing it
self.clone().split_off(count)
}
/// Construct a vector of the first `count` elements from the
/// current vector.
///
/// Time: O(log n)
pub fn take(&self, count: usize) -> Self {
// FIXME can be made more efficient by dropping the unwanted side without constructing it
let mut left = self.clone();
left.split_off(count);
left
}
/// Truncate a vector to the given size.
///
/// Discards all elements in the vector beyond the given length.
///
/// Panics if the new length is greater than the current length.
///
/// Time: O(log n)
pub fn truncate(&mut self, len: usize) {
// FIXME can be made more efficient by dropping the unwanted side without constructing it
self.split_off(len);
}
#[cfg(has_range_bound)]
/// Extract a slice from a vector.
///
/// Remove the elements from `start_index` until `end_index` in
/// the current vector and return the removed slice as a new
/// vector.
///
/// Time: O(log n)
pub fn slice<R>(&mut self, range: R) -> Self
where
R: RangeBounds<usize>,
{
let start_index = match range.start_bound() {
Bound::Included(i) => *i,
Bound::Excluded(i) => *i + 1,
Bound::Unbounded => 0,
};
let end_index = match range.end_bound() {
Bound::Included(i) => *i + 1,
Bound::Excluded(i) => *i,
Bound::Unbounded => self.len(),
};
if start_index >= end_index || start_index >= self.len() {
return Vector::new();
}
let mut middle = self.split_off(start_index);
let right = middle.split_off(end_index - start_index);
self.append(right);
middle
}
/// Insert an element into a vector.
///
/// Insert an element at position `index`, shifting all elements
/// after it to the right.
///
/// ## Performance Note
///
/// While `push_front` and `push_back` are heavily optimised
/// operations, `insert` in the middle of a vector requires a
/// split, a push, and an append. Thus, if you want to insert
/// many elements at the same location, instead of `insert`ing
/// them one by one, you should rather create a new vector
/// containing the elements to insert, split the vector at the
/// insertion point, and append the left hand, the new vector and
/// the right hand in order.
///
/// Time: O(log n)
pub fn insert(&mut self, index: usize, value: A) {
if index == 0 {
return self.push_front(value);
}
if index == self.len() {
return self.push_back(value);
}
// TODO a lot of optimisations still possible here
assert!(index < self.len());
let right = self.split_off(index);
self.push_back(value);
self.append(right);
}
/// Remove an element from a vector.
///
/// Remove the element from position 'index', shifting all
/// elements after it to the left, and return the removec element.
///
/// ## Performance Note
///
/// While `pop_front` and `pop_back` are heavily optimised
/// operations, `remove` in the middle of a vector requires a
/// split, a pop, and an append. Thus, if you want to remove many
/// elements from the same location, instead of `remove`ing them
/// one by one, it is much better to use [`slice`][slice].
///
/// Time: O(log n)
///
/// [slice]: #method.slice
pub fn remove(&mut self, index: usize) -> A {
assert!(index < self.len());
if index == 0 {
return self.pop_front().unwrap();
}
if index == self.len() - 1 {
return self.pop_back().unwrap();
}
// TODO a lot of optimisations still possible here
let mut right = self.split_off(index);
let value = right.pop_front().unwrap();
self.append(right);
value
}
/// Discard all elements from the vector.
///
/// This leaves you with an empty vector, and all elements that
/// were previously inside it are dropped.
///
/// Time: O(n)
pub fn clear(&mut self) {
if !self.is_empty() {
self.length = 0;
self.middle_level = 0;
if !self.outer_f.is_empty() {
self.outer_f = Ref::<Chunk<A>>::default();
}
if !self.inner_f.is_empty() {
self.inner_f = Ref::<Chunk<A>>::default();
}
if !self.middle.is_empty() {
self.middle = Ref::<Node<A>>::default();
}
if !self.inner_b.is_empty() {
self.inner_b = Ref::<Chunk<A>>::default();
}
if !self.outer_b.is_empty() {
self.outer_b = Ref::<Chunk<A>>::default();
}
}
}
/// Binary search a sorted vector for a given element using a comparator
/// function.
///
/// Assumes the vector has already been sorted using the same comparator
/// function, eg. by using [`sort_by`][sort_by].
///
/// If the value is found, it returns `Ok(index)` where `index` is the index
/// of the element. If the value isn't found, it returns `Err(index)` where
/// `index` is the index at which the element would need to be inserted to
/// maintain sorted order.
///
/// Time: O(log n)
///
/// [sort_by]: #method.sort_by
pub fn binary_search_by<F>(&self, mut f: F) -> Result<usize, usize>
where
F: FnMut(&A) -> Ordering,
{
let mut size = self.len();
if size == 0 {
return Err(0);
}
let mut base = 0;
while size > 1 {
let half = size / 2;
let mid = base + half;
base = match f(&self[mid]) {
Ordering::Greater => base,
_ => mid,
};
size -= half;
}
match f(&self[base]) {
Ordering::Equal => Ok(base),
Ordering::Greater => Err(base),
Ordering::Less => Err(base + 1),
}
}
/// Binary search a sorted vector for a given element.
///
/// If the value is found, it returns `Ok(index)` where `index` is the index
/// of the element. If the value isn't found, it returns `Err(index)` where
/// `index` is the index at which the element would need to be inserted to
/// maintain sorted order.
///
/// Time: O(log n)
pub fn binary_search(&self, value: &A) -> Result<usize, usize>
where
A: Ord,
{
self.binary_search_by(|e| e.cmp(value))
}
/// Binary search a sorted vector for a given element with a key extract
/// function.
///
/// Assumes the vector has already been sorted using the same key extract
/// function, eg. by using [`sort_by_key`][sort_by_key].
///
/// If the value is found, it returns `Ok(index)` where `index` is the index
/// of the element. If the value isn't found, it returns `Err(index)` where
/// `index` is the index at which the element would need to be inserted to
/// maintain sorted order.
///
/// Time: O(log n)
///
/// [sort_by_key]: #method.sort_by_key
pub fn binary_search_by_key<B, F>(&self, b: &B, mut f: F) -> Result<usize, usize>
where
F: FnMut(&A) -> B,
B: Ord,
{
self.binary_search_by(|k| f(k).cmp(b))
}
/// Insert an element into a sorted vector.
///
/// Insert an element into a vector in sorted order, assuming the vector is
/// already in sorted order.
///
/// Time: O(log n)
///
/// # Examples
///
/// ```
/// # #[macro_use] extern crate im;
/// # use im::vector::Vector;
/// # fn main() {
/// let mut vec = vector![1, 2, 3, 7, 8, 9];
/// vec.insert_ord(5);
/// assert_eq!(vector![1, 2, 3, 5, 7, 8, 9], vec);
/// # }
/// ```
pub fn insert_ord(&mut self, item: A)
where
A: Ord,
{
match self.binary_search(&item) {
Ok(index) => self.insert(index, item),
Err(index) => self.insert(index, item),
}
}
/// Sort a vector.
///
/// Time: O(n log n)
///
/// # Examples
///
/// ```
/// # #[macro_use] extern crate im;
/// # use im::vector::Vector;
/// # fn main() {
/// let mut vec = vector![3, 2, 5, 4, 1];
/// vec.sort();
/// assert_eq!(vector![1, 2, 3, 4, 5], vec);
/// # }
/// ```
pub fn sort(&mut self)
where
A: Ord,
{
self.sort_by(Ord::cmp)
}
/// Sort a vector using a comparator function.
///
/// Time: O(n log n)
///
/// # Examples
///
/// ```
/// # #[macro_use] extern crate im;
/// # use im::vector::Vector;
/// # fn main() {
/// let mut vec = vector![3, 2, 5, 4, 1];
/// vec.sort_by(|left, right| left.cmp(right));
/// assert_eq!(vector![1, 2, 3, 4, 5], vec);
/// # }
/// ```
pub fn sort_by<F>(&mut self, cmp: F)
where
F: Fn(&A, &A) -> Ordering,
{
let len = self.len();
if len > 1 {
sort::quicksort(self, 0, len - 1, &cmp);
}
}
// Implementation details
fn prune(&mut self) {
while self.middle_level > 0 && self.middle.is_single() {
self.middle = self.middle.first_child().clone();
self.middle_level -= 1;
}
}
fn push_middle(&mut self, side: Side, chunk: Ref<Chunk<A>>) {
let new_middle = {
let middle = Ref::make_mut(&mut self.middle);
match middle.push_chunk(self.middle_level, side, chunk) {
PushResult::Done => return,
PushResult::Full(chunk) => Ref::from({
match side {
Side::Left => Node::from_chunk(self.middle_level, chunk)
.join_branches(middle.clone(), self.middle_level),
Side::Right => middle.clone().join_branches(
Node::from_chunk(self.middle_level, chunk),
self.middle_level,
),
}
}),
}
};
self.middle_level += 1;
self.middle = new_middle;
}
fn pop_middle(&mut self, side: Side) -> Option<Ref<Chunk<A>>> {
let chunk = {
let middle = Ref::make_mut(&mut self.middle);
match middle.pop_chunk(self.middle_level, side) {
PopResult::Empty => return None,
PopResult::Done(chunk) => chunk,
PopResult::Drained(chunk) => {
middle.clear_node();
self.middle_level = 0;
chunk
}
}
};
Some(chunk)
}
}
#[inline]
fn replace_def<A: Default>(dest: &mut A) -> A {
replace(dest, Default::default())
}
// Core traits
impl<A: Clone> Default for Vector<A> {
fn default() -> Self {
Self::new()
}
}
impl<A> Clone for Vector<A> {
fn clone(&self) -> Self {
Vector {
length: self.length,
middle_level: self.middle_level,
outer_f: self.outer_f.clone(),
inner_f: self.inner_f.clone(),
middle: self.middle.clone(),
inner_b: self.inner_b.clone(),
outer_b: self.outer_b.clone(),
}
}
}
impl<A: Clone + Debug> Debug for Vector<A> {
fn fmt(&self, f: &mut Formatter) -> Result<(), Error> {
f.debug_list().entries(self.iter()).finish()
}
}
#[cfg(not(has_specialisation))]
impl<A: Clone + PartialEq> PartialEq for Vector<A> {
fn eq(&self, other: &Self) -> bool {
if self.len() != other.len() {
return false;
}
self.iter().eq(other.iter())
}
}
#[cfg(has_specialisation)]
impl<A: Clone + PartialEq> PartialEq for Vector<A> {
default fn eq(&self, other: &Self) -> bool {
if self.len() != other.len() {
return false;
}
self.iter().eq(other.iter())
}
}
#[cfg(has_specialisation)]
impl<A: Clone + Eq> PartialEq for Vector<A> {
fn eq(&self, other: &Self) -> bool {
if self.len() != other.len() || self.middle_level != other.middle_level {
return false;
}
fn cmp_chunk<A>(left: &Ref<Chunk<A>>, right: &Ref<Chunk<A>>) -> bool {
(left.is_empty() && right.is_empty()) || Ref::ptr_eq(left, right)
}
if cmp_chunk(&self.outer_f, &other.outer_f) && cmp_chunk(&self.inner_f, &other.inner_f)
&& ((self.middle.is_empty() && other.middle.is_empty())
|| Ref::ptr_eq(&self.middle, &other.middle))
&& cmp_chunk(&self.inner_b, &other.inner_b)
&& cmp_chunk(&self.outer_b, &other.outer_b)
{
return true;
}
self.iter().eq(other.iter())
}
}
impl<A: Clone + Eq> Eq for Vector<A> {}
impl<A: Clone + PartialOrd> PartialOrd for Vector<A> {
fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
self.iter().partial_cmp(other.iter())
}
}
impl<A: Clone + Ord> Ord for Vector<A> {
fn cmp(&self, other: &Self) -> Ordering {
self.iter().cmp(other.iter())
}
}
impl<A: Clone + Hash> Hash for Vector<A> {
fn hash<H: Hasher>(&self, state: &mut H) {
for i in self {
i.hash(state)
}
}
}
impl<A: Clone> Sum for Vector<A> {
fn sum<I>(it: I) -> Self
where
I: Iterator<Item = Self>,
{
it.fold(Self::new(), |a, b| a + b)
}
}
impl<A: Clone> Add for Vector<A> {
type Output = Vector<A>;
/// Concatenate two vectors.
///
/// Time: O(log n)
fn add(mut self, other: Self) -> Self::Output {
self.append(other);
self
}
}
impl<'a, A: Clone> Add for &'a Vector<A> {
type Output = Vector<A>;
/// Concatenate two vectors.
///
/// Time: O(log n)
fn add(self, other: Self) -> Self::Output {
let mut out = self.clone();
out.append(other.clone());
out
}
}
impl<A: Clone> Extend<A> for Vector<A> {
/// Add values to the end of a vector by consuming an iterator.
///
/// Time: O(n)
fn extend<I>(&mut self, iter: I)
where
I: IntoIterator<Item = A>,
{
for item in iter {
self.push_back(item)
}
}
}
impl<A: Clone> Index<usize> for Vector<A> {
type Output = A;
/// Get a reference to the value at index `index` in the vector.
///
/// Time: O(log n)
fn index(&self, index: usize) -> &Self::Output {
match self.get(index) {
Some(value) => value,
None => panic!(
"Vector::index: index out of bounds: {} < {}",
index,
self.len()
),
}
}
}
impl<A: Clone> IndexMut<usize> for Vector<A> {
/// Get a mutable reference to the value at index `index` in the
/// vector.
///
/// Time: O(log n)
fn index_mut(&mut self, index: usize) -> &mut Self::Output {
match self.get_mut(index) {
Some(value) => value,
None => panic!("Vector::index_mut: index out of bounds"),
}
}
}
// Conversions
impl<'a, A: Clone> IntoIterator for &'a Vector<A> {
type Item = &'a A;
type IntoIter = Iter<'a, A>;
fn into_iter(self) -> Self::IntoIter {
self.iter()
}
}
impl<A: Clone> IntoIterator for Vector<A> {
type Item = A;
type IntoIter = ConsumingIter<A>;
fn into_iter(self) -> Self::IntoIter {
ConsumingIter::new(self)
}
}
impl<A: Clone> FromIterator<A> for Vector<A> {
/// Create a vector from an iterator.
///
/// Time: O(n)
fn from_iter<I>(iter: I) -> Self
where
I: IntoIterator<Item = A>,
{
let mut seq = Self::new();
for item in iter {
seq.push_back(item)
}
seq
}
}
impl<'s, 'a, A, OA> From<&'s Vector<&'a A>> for Vector<OA>
where
A: ToOwned<Owned = OA>,
OA: Borrow<A> + Clone,
{
fn from(vec: &Vector<&A>) -> Self {
vec.iter().map(|a| (*a).to_owned()).collect()
}
}
impl<'a, A: Clone> From<&'a [A]> for Vector<A> {
fn from(slice: &[A]) -> Self {
slice.into_iter().cloned().collect()
}
}
impl<A: Clone> From<Vec<A>> for Vector<A> {
/// Create a vector from a [`std::vec::Vec`][vec].
///
/// Time: O(n)
///
/// [vec]: https://doc.rust-lang.org/std/vec/struct.Vec.html
fn from(vec: Vec<A>) -> Self {
vec.into_iter().collect()
}
}
impl<'a, A: Clone> From<&'a Vec<A>> for Vector<A> {
/// Create a vector from a [`std::vec::Vec`][vec].
///
/// Time: O(n)
///
/// [vec]: https://doc.rust-lang.org/std/vec/struct.Vec.html
fn from(vec: &Vec<A>) -> Self {
vec.into_iter().cloned().collect()
}
}
// Iterators
/// An iterator over vectors with values of type `A`.
///
/// To obtain one, use [`Vector::iter()`][iter].
///
/// [iter]: struct.Vector.html#method.iter
pub struct Iter<'a, A: 'a> {
iter: Chain<
Chain<Chain<Chain<ChunkIter<'a, A>, ChunkIter<'a, A>>, NodeIter<'a, A>>, ChunkIter<'a, A>>,
ChunkIter<'a, A>,
>,
}
impl<'a, A: Clone> Iter<'a, A> {
fn new(seq: &'a Vector<A>) -> Self {
let outer_f = seq.outer_f.iter();
let inner_f = seq.inner_f.iter();
let middle = NodeIter::new(&seq.middle);
let inner_b = seq.inner_b.iter();
let outer_b = seq.outer_b.iter();
Iter {
iter: outer_f
.chain(inner_f)
.chain(middle)
.chain(inner_b)
.chain(outer_b),
}
}
}
impl<'a, A: Clone> Iterator for Iter<'a, A> {
type Item = &'a A;
/// Advance the iterator and return the next value.
///
/// Time: O(1)*
fn next(&mut self) -> Option<Self::Item> {
self.iter.next()
}
fn size_hint(&self) -> (usize, Option<usize>) {
self.iter.size_hint()
}
}
impl<'a, A: Clone> DoubleEndedIterator for Iter<'a, A> {
/// Advance the iterator and return the next value.
///
/// Time: O(1)*
fn next_back(&mut self) -> Option<Self::Item> {
self.iter.next_back()
}
}
impl<'a, A: Clone> ExactSizeIterator for Iter<'a, A> {}
impl<'a, A: Clone> FusedIterator for Iter<'a, A> {}
/// A mutable iterator over vectors with values of type `A`.
///
/// To obtain one, use [`Vector::iter_mut()`][iter_mut].
///
/// [iter_mut]: struct.Vector.html#method.iter_mut
pub struct IterMut<'a, A: 'a> {
iter: Chain<
Chain<
Chain<Chain<ChunkIterMut<'a, A>, ChunkIterMut<'a, A>>, NodeIterMut<'a, A>>,
ChunkIterMut<'a, A>,
>,
ChunkIterMut<'a, A>,
>,
}
impl<'a, A: Clone> IterMut<'a, A> {
fn new(seq: &'a mut Vector<A>) -> Self {
let outer_f = Ref::make_mut(&mut seq.outer_f).iter_mut();
let inner_f = Ref::make_mut(&mut seq.inner_f).iter_mut();
let middle = NodeIterMut::new(Ref::make_mut(&mut seq.middle), seq.middle_level);
let inner_b = Ref::make_mut(&mut seq.inner_b).iter_mut();
let outer_b = Ref::make_mut(&mut seq.outer_b).iter_mut();
IterMut {
iter: outer_f
.chain(inner_f)
.chain(middle)
.chain(inner_b)
.chain(outer_b),
}
}
}
impl<'a, A: Clone> Iterator for IterMut<'a, A> {
type Item = &'a mut A;
/// Advance the iterator and return the next value.
///
/// Time: O(log n)
fn next(&mut self) -> Option<Self::Item> {
self.iter.next()
}
fn size_hint(&self) -> (usize, Option<usize>) {
self.iter.size_hint()
}
}
impl<'a, A: Clone> DoubleEndedIterator for IterMut<'a, A> {
/// Remove and return an element from the back of the iterator.
///
/// Time: O(log n)
fn next_back(&mut self) -> Option<Self::Item> {
self.iter.next_back()
}
}
impl<'a, A: Clone> ExactSizeIterator for IterMut<'a, A> {}
impl<'a, A: Clone> FusedIterator for IterMut<'a, A> {}
/// A consuming iterator over vectors with values of type `A`.
pub struct ConsumingIter<A> {
iter: Chain<
Chain<
Chain<Chain<ConsumingChunkIter<A>, ConsumingChunkIter<A>>, ConsumingNodeIter<A>>,
ConsumingChunkIter<A>,
>,
ConsumingChunkIter<A>,
>,
}
impl<A: Clone> ConsumingIter<A> {
fn new(seq: Vector<A>) -> Self {
let outer_f = clone_ref(seq.outer_f).into_iter();
let inner_f = clone_ref(seq.inner_f).into_iter();
let middle = ConsumingNodeIter::new(clone_ref(seq.middle), seq.middle_level);
let inner_b = clone_ref(seq.inner_b).into_iter();
let outer_b = clone_ref(seq.outer_b).into_iter();
ConsumingIter {
iter: outer_f
.chain(inner_f)
.chain(middle)
.chain(inner_b)
.chain(outer_b),
}
}
}
impl<A: Clone> Iterator for ConsumingIter<A> {
type Item = A;
/// Advance the iterator and return the next value.
///
/// Time: O(1)*
fn next(&mut self) -> Option<Self::Item> {
self.iter.next()
}
}
impl<A: Clone> DoubleEndedIterator for ConsumingIter<A> {
fn next_back(&mut self) -> Option<Self::Item> {
self.iter.next_back()
}
}
impl<A: Clone> ExactSizeIterator for ConsumingIter<A> {}
impl<A: Clone> FusedIterator for ConsumingIter<A> {}
// QuickCheck
#[cfg(all(feature = "arc", any(test, feature = "quickcheck")))]
use quickcheck::{Arbitrary, Gen};
#[cfg(all(feature = "arc", any(test, feature = "quickcheck")))]
impl<A: Arbitrary + Sync + Clone> Arbitrary for Vector<A> {
fn arbitrary<G: Gen>(g: &mut G) -> Self {
Vector::from_iter(Vec::<A>::arbitrary(g))
}
}
// Proptest
#[cfg(any(test, feature = "proptest"))]
pub mod proptest {
use super::*;
use proptest::collection::vec;
use proptest::strategy::{BoxedStrategy, Strategy, ValueTree};
use std::ops::Range;
/// A strategy for generating a vector of a certain size.
///
/// # Examples
///
/// ```rust,ignore
/// proptest! {
/// #[test]
/// fn proptest_a_vector(ref l in vector(".*", 10..100)) {
/// assert!(l.len() < 100);
/// assert!(l.len() >= 10);
/// }
/// }
/// ```
pub fn vector<A: Strategy + 'static>(
element: A,
size: Range<usize>,
) -> BoxedStrategy<Vector<<A::Tree as ValueTree>::Value>>
where
<A::Tree as ValueTree>::Value: Clone,
{
vec(element, size).prop_map(Vector::from_iter).boxed()
}
}
// Tests
#[cfg(test)]
mod test {
use super::*;
use proptest::collection::vec;
use proptest::num::{i32, usize};
// #[test]
// fn push_and_pop_things() {
// let mut seq = Vector::new();
// for i in 0..1000 {
// seq.push_back(i);
// }
// for i in 0..1000 {
// assert_eq!(Some(i), seq.pop_front());
// }
// assert!(seq.is_empty());
// for i in 0..1000 {
// seq.push_front(i);
// }
// for i in 0..1000 {
// assert_eq!(Some(i), seq.pop_back());
// }
// assert!(seq.is_empty());
// }
#[test]
fn macro_allows_trailing_comma() {
let vec1 = vector![1, 2, 3];
let vec2 = vector![1, 2, 3,];
assert_eq!(vec1, vec2);
}
#[test]
fn indexing() {
let vec1 = vector![0, 1, 2, 3, 4, 5];
let mut vec2 = vec1.clone();
vec2.push_front(0);
assert_eq!(0, *vec2.get(0).unwrap());
assert_eq!(0, vec2[0]);
}
proptest! {
#[test]
fn iter(ref vec in vec(i32::ANY, 0..1000)) {
let seq: Vector<i32> = Vector::from_iter(vec.iter().cloned());
for (index, item) in seq.iter().enumerate() {
assert_eq!(&vec[index], item);
}
assert_eq!(vec.len(), seq.len());
}
#[test]
fn push_front_mut(ref input in vec(i32::ANY, 0..1000)) {
let mut vector = Vector::new();
for (count, value) in input.iter().cloned().enumerate() {
assert_eq!(count, vector.len());
vector.push_front(value);
assert_eq!(count + 1, vector.len());
}
let input2 = Vec::from_iter(input.iter().rev().cloned());
assert_eq!(input2, Vec::from_iter(vector.iter().cloned()));
}
#[test]
fn push_back_mut(ref input in vec(i32::ANY, 0..1000)) {
let mut vector = Vector::new();
for (count, value) in input.iter().cloned().enumerate() {
assert_eq!(count, vector.len());
vector.push_back(value);
assert_eq!(count + 1, vector.len());
}
assert_eq!(input, &Vec::from_iter(vector.iter().cloned()));
}
#[test]
fn pop_back_mut(ref input in vec(i32::ANY, 0..1000)) {
let mut vector = Vector::from_iter(input.iter().cloned());
assert_eq!(input.len(), vector.len());
for (index, value) in input.iter().cloned().enumerate().rev() {
match vector.pop_back() {
None => panic!("vector emptied unexpectedly"),
Some(item) => {
assert_eq!(index, vector.len());
assert_eq!(value, item);
}
}
}
assert_eq!(0, vector.len());
}
#[test]
fn pop_front_mut(ref input in vec(i32::ANY, 0..1000)) {
let mut vector = Vector::from_iter(input.iter().cloned());
assert_eq!(input.len(), vector.len());
for (index, value) in input.iter().cloned().rev().enumerate().rev() {
match vector.pop_front() {
None => panic!("vector emptied unexpectedly"),
Some(item) => {
assert_eq!(index, vector.len());
assert_eq!(value, item);
}
}
}
assert_eq!(0, vector.len());
}
// #[test]
// fn push_and_pop(ref input in vec(i32::ANY, 0..1000)) {
// let mut vector = Vector::new();
// for (count, value) in input.iter().cloned().enumerate() {
// assert_eq!(count, vector.len());
// vector.push_back(value);
// assert_eq!(count + 1, vector.len());
// }
// for (index, value) in input.iter().cloned().rev().enumerate().rev() {
// match vector.pop_front() {
// None => panic!("vector emptied unexpectedly"),
// Some(item) => {
// assert_eq!(index, vector.len());
// assert_eq!(value, item);
// }
// }
// }
// assert_eq!(true, vector.is_empty());
// }
#[test]
fn split(ref vec in vec(i32::ANY, 0..2000), split_pos in usize::ANY) {
if !vec.is_empty() {
let split_index = split_pos % vec.len();
let mut left = Vector::from_iter(vec.iter().cloned());
let right = left.split_off(split_index);
assert_eq!(left.len(), split_index);
assert_eq!(right.len(), vec.len() - split_index);
for (index, item) in left.iter().enumerate() {
assert_eq!(&vec[index], item);
}
for (index, item) in right.iter().enumerate() {
assert_eq!(&vec[split_index + index], item);
}
}
}
#[test]
fn append(ref vec1 in vec(i32::ANY, 0..1000), ref vec2 in vec(i32::ANY, 0..1000)) {
let mut seq1 = Vector::from_iter(vec1.iter().cloned());
let seq2 = Vector::from_iter(vec2.iter().cloned());
assert_eq!(seq1.len(), vec1.len());
assert_eq!(seq2.len(), vec2.len());
seq1.append(seq2);
let mut vec = vec1.clone();
vec.extend(vec2);
assert_eq!(seq1.len(), vec.len());
for (index, item) in seq1.into_iter().enumerate() {
assert_eq!(vec[index], item);
}
}
}
}