Ds\Stack

Complexity

Total Complexity

18

Size/Duplication

Total Lines	164
Duplicated Lines	100 %

Coupling/Cohesion

Components	1
Dependencies	2

Test Coverage

Coverage

97.44%

Importance

Changes

0

15 Methods

Rating	Name	Duplication	Size	Complexity
A	__construct()	4	4	2
A	clear()	4	4	1
A	copy()	4	4	1
A	count()	4	4	1
A	allocate()	4	4	1
A	capacity()	4	4	1
A	peek()	4	4	1
A	pop()	4	4	1
A	push()	4	4	1
A	toArray()	4	4	1
A	getIterator()	6	6	2
A	offsetSet()	8	8	2
A	offsetGet()	4	4	1
A	offsetUnset()	4	4	1
A	offsetExists()	4	4	1

<?php
namespace Ds;

use Error;
use UnderflowException;

/**
 * Stack
 *
 * @package Ds
 */
final class Stack implements \IteratorAggregate, \ArrayAccess, Collection

This class seems to be duplicated in your project.

{
    use Traits\Collection;

    /**
     * @var Vector
     */
    private $internal;

    /**
     * Creates an instance using the values of an array or Traversable object.
     *
     * @param array|\Traversable $values

Should the type for parameter $values not be array|\Traversable|null? Also, consider making the array more specific, something like array<String>, or String[].

     */
    public function __construct($values = null)
    {
        $this->internal = new Vector($values ?: []);
    }

    /**
     * Clear all elements in the Stack
     */
    public function clear()
    {
        $this->internal->clear();
    }

    /**
     * @inheritdoc
     */
    public function copy(): Collection
    {
        return new self($this->internal);
    }

    /**
     * Returns the number of elements in the Stack
     *
     * @return int
     */
    public function count(): int
    {
        return count($this->internal);
    }

    /**
     * Ensures that enough memory is allocated for a specified capacity. This
     * potentially reduces the number of reallocations as the size increases.
     *
     * @param int $capacity The number of values for which capacity should be
     *                      allocated. Capacity will stay the same if this value
     *                      is less than or equal to the current capacity.
     */
    public function allocate(int $capacity)
    {
        $this->internal->allocate($capacity);
    }

    /**
     * Returns the current capacity of the stack.
     *
     * @return int
     */
    public function capacity(): int
    {
        return $this->internal->capacity();
    }

    /**
     * Returns the value at the top of the stack without removing it.
     *
     * @return mixed
     *
     * @throws UnderflowException if the stack is empty.
     */
    public function peek()
    {
        return $this->internal->last();
    }

    /**
     * Returns and removes the value at the top of the stack.
     *
     * @return mixed
     *
     * @throws UnderflowException if the stack is empty.
     */
    public function pop()
    {
        return $this->internal->pop();
    }

    /**
     * Pushes zero or more values onto the top of the stack.
     *
     * @param mixed ...$values
     */

Consider making the type for parameter $values a bit more specific; maybe use array.

    public function push(...$values)
    {
        $this->internal->push(...$values);
    }

    /**
     * @inheritDoc
     */
    public function toArray(): array
    {
        return array_reverse($this->internal->toArray());
    }

    /**
     *
     */
    public function getIterator()
    {
        while ( ! $this->isEmpty()) {
            yield $this->pop();
        }
    }

    /**
     * @inheritdoc
     *
     * @throws Error
     */
    public function offsetSet($offset, $value)
    {
        if ($offset === null) {
            $this->push($value);
        } else {
            throw new Error();
        }
    }

    /**
     * @inheritdoc
     *
     * @throws Error
     */
    public function offsetGet($offset)
    {
        throw new Error();
    }

    /**
     * @inheritdoc
     *
     * @throws Error
     */
    public function offsetUnset($offset)
    {
        throw new Error();
    }

    /**
     * @inheritdoc
     *
     * @throws Error
     */
    public function offsetExists($offset)
    {
        throw new Error();
    }
}