DoublyLinkedList - Code Metrics - Inspection of "Moved insert method to ListAbstract class" - SiroDiaz/DataStructures - Measure and Improve Code Quality continuously with Scrutinizer

Completed

Push — master ( b02a4e...93d881 )

by Siro Díaz

created 2017-07-14 23:29 UTC

DoublyLinkedList C

↳ Parent: Project

Complexity

Total Complexity

Size/Duplication

Total Lines	443
Duplicated Lines	30.25 %

Coupling/Cohesion

Components	1
Dependencies	3

Importance

Changes	1
Bugs	0	Features	1

Metric	Value
wmc	63
lcom	1
cbo	3
dl	134
loc	443
rs	5.8893
c	1
b	0
f	1

24 Methods

Rating	Name	Duplication	Size	Complexity
A	__construct()	7	7	1
A	clear()	0	5	2
A	get()	8	8	2
C	search()	0	30	8
A	getLast()	0	6	2
A	searchLast()	0	6	2
A	contains()	0	17	4
A	indexOf()	19	19	4
A	lastIndexOf()	19	19	4
B	remove()	10	29	5
A	getAll()	17	17	4
A	insertBeginning()	0	14	2
A	insertEnd()	0	8	1
A	insertAt()	0	16	2
C	delete()	27	27	8
A	deleteBeginning()	8	8	1
A	deleteAt()	0	19	2
A	deleteEnd()	19	19	2
A	toArray()	0	8	2
A	rewind()	0	4	1
A	current()	0	3	1
A	key()	0	3	1
A	next()	0	4	1
A	valid()	0	3	1

How to fix Duplicated Code Complexity

Duplicated Code

Duplicate code is one of the most pungent code smells. A rule that is often used is to re-structure code once it is duplicated in three or more places.

Common duplication problems, and corresponding solutions are:

If you have the same expression in different places: Extract expression to a method
If you have the same method in different sub-classes: Extract method, and pull up field to the parent class
If you have the same code in unrelated classes: Consider extracting the code to a new class, and injecting that class

Complex Class

Tip: Before tackling complexity, make sure that you eliminate any duplication first. This often can reduce the size of classes significantly.

Complex classes like DoublyLinkedList often do a lot of different things. To break such a class down, we need to identify a cohesive component within that class. A common approach to find such a component is to look for fields/methods that share the same prefixes, or suffixes. You can also have a look at the cohesion graph to spot any un-connected, or weakly-connected components.

Once you have determined the fields that belong together, you can apply the Extract Class refactoring. If the component makes sense as a sub-class, Extract Subclass is also a candidate, and is often faster.

While breaking up the class, it is a good idea to analyze how other classes use DoublyLinkedList, and based on these observations, apply Extract Interface, too.

<?php
/**
 * DataStructures for PHP
 *
 * @link      https://github.com/SiroDiaz/DataStructures
 * @copyright Copyright (c) 2017 Siro Díaz Palazón
 * @license   https://github.com/SiroDiaz/DataStructures/blob/master/README.md (MIT License)
 */
namespace DataStructures\Lists;

use DataStructures\Lists\Traits\{CountTrait, ArrayAccessTrait};
use DataStructures\Lists\Nodes\DoublyLinkedListNode;
use DataStructures\Lists\ListAbstract;
use OutOfBoundsException;

/**
 * DoublyLinkedList
 *
 * DoublyLinkedList is a double linked list that has
 * a pointer to the next and the previous node.
 *
 * @author Siro Diaz Palazon <[email protected]>
 */
class DoublyLinkedList extends ListAbstract {
    use ArrayAccessTrait;

    private $head;
    private $tail;
    private $position;
    private $current;

    public function __construct() {

        $this->head = null;
        $this->tail = &$this->head;
        $this->size = 0;
        $this->position = 0;
        $this->current = &$this->head;
    }

    /**
     * Removes all nodes of the list. It removes from the beginning.
     */
    public function clear() {
        while($this->head !== null) {
            $this->shift();
        }
    }
    
    /**
     * Gets the data stored in the position especified.
     *
     * @param integer $index Index that must be greater than 0
     *  and lower than the list size.
     * @return mixed The data stored in the given index
     * @throws OutOfBoundsException if index is out bounds.
     */
    public function get($index) {

        $node = $this->search($index);
        if($node === null) {
            return null;
        }

        return $node->data;
    }

    /**
     * Gets the node stored in the position especified.
     * If index is 0 or (size - 1) the method is O(1) else O(n).
     *
     * @param integer $index the position.
     * @throws OutOfBoundsException if it is out of limits (< 0 or > size - 1)
     * @return DataStructures\Lists\Nodes\DoublyLinkedListNode|null the node stored in $index.
     */
    protected function search($index) {
        if($index < 0 || $index > $this->size - 1) {
            throw new OutOfBoundsException();
        }

        if($index === 0) {
            return $this->head;

        }

        if($index === $this->size - 1) {
            return $this->tail;

        }

        $current = &$this->head;
        if($index < (int) ceil($this->size / 2)) {
            $i = 0;
            while($i < $index) {
                $current = &$current->next;
                $i++;
            }    
        } else {
            $i = $this->size;
            while($i > $index) {
                $current = &$current->prev;
                $i--;
            }
        }

        return $current;
    }

    /**
     * Returns the data in the last node with O(1).
     *
     * @return mixed null if the list is empty.
     */
    public function getLast() {
        if($this->head === null) {
            return null;
        }
        return $this->tail->data;
    }

    /**
     * Returns the last node with O(1).
     *
     * @return DataStructures\Lists\Nodes\DoublyLinkedListNode|null if the list is empty.
     */
    public function searchLast() {
        if($this->head === null) {
            return null;
        }
        return $this->tail;
    }

    /**
     * {@inheritDoc}
     */
    public function contains($data) : bool {
        if($this->empty()) {
            return false;
        }

        $current = $this->head->next;
        $prev = $this->head;
        while($current !== $this->head) {
            if($prev->data === $data) {
                return true;
            }
            $prev = $current;
            $current = $current->next;
        }

        return false;
    }

    /**
     * {@inheritDoc}
     */
    public function indexOf($data) {

        if($this->head === null) {
            return false;
        }
        
        $current = $this->head;
        $i = 0;
        
        while($i < $this->size) {
            if($current->data === $data) {
                return $i;
            }

            $current = $current->next;
            $i++;
        }

        return false;
    }

    /**
     * {@inheritDoc}
     */
    public function lastIndexOf($data) {

        if($this->head === null) {
            return false;
        }
        
        $current = $this->head;
        $i = 0;
        $pos = false;
        while($i < $this->size) {
            if($current->data == $data) {
                $pos = $i;
            }

            $current = $current->next;
            $i++;
        }

        return $pos;
    }

    /**
     * {@inheritDoc}
     */
    public function remove($data) {
        $current = &$this->head;
        $i = 0;
        
        if($this->head === null) {
            return null;
        }

        if($this->head->data === $data) {
            $this->head = &$this->head->next;
            $this->head->prev = &$this->tail;
            $this->size--;
            
            return $data;
        }

        while($i < $this->size) {

            if($current->data === $data) {
                $current->prev = &$current->next;
                $current = null;
                $this->size--;
                return $data;
            }

            $current = $current->next;
        }

        return null;
    }
    
    /**
     * Generator for retrieve all nodes stored.
     * 
     * @return null if the head is null (or list is empty)
     */
    public function getAll() {

        if($this->head === null) {
            return;
        }

        if($this->head === $this->tail) {
            yield $this->head->data;
        } else {
            $current = $this->head;
            $i = 0;
            while($i < $this->size) {
                yield $current->data;
                $current = $current->next;
                $i++;
            }
        }
    }

    /**
     * Inserts at the beginning of the list.
     *
     * @param mixed $data
     */
    protected function insertBeginning($data) {
        $newNode = new DoublyLinkedListNode($data);
        if($this->head === null) {
            $newNode->next = &$this->head;
            $newNode->prev = &$this->head;
            $this->head = &$newNode;
            $this->tail = &$newNode;
        } else {
            $this->tail->next = &$newNode;
            $newNode->next = &$this->head;
            $newNode->prev = &$this->tail;
            $this->head = &$newNode;
        }
    }

    /**
     * Add a new node in the specified index.
     *
     * @param mixed $data the data to be stored.
     */
    protected function insertEnd($data) {
        $newNode = new DoublyLinkedListNode($data);
        $this->tail->next = &$newNode;
        $newNode->next = &$this->head;
        $newNode->prev = &$this->tail;
        $this->tail = &$newNode;
        $this->head->prev = &$newNode;
    }

    /**
     * Add a new node in the specified index.
     *
     * @param integer $index the position.
     * @param mixed $data the data to be stored.
     */
    protected function insertAt($index, $data) {
        $newNode = new DoublyLinkedListNode($data);
        $current = $this->head;
        $prev = null;
        $i = 0;
        while($i < $index) {
            $prev = $current;
            $current = $current->next;
            $i++;
        }
        
        $prev->next = &$newNode;
        $newNode->prev = &$prev;
        $newNode->next = &$current;
        $current->prev = &$newNode;
    }
    
    /**
     * Delete a node in the given position and returns it back.
     *
     * @param integer $index the position.
     * @throws OutOfBoundsException if index is negative
     *  or is greater than the size of the list.
     */
    public function delete($index) {

        if($index < 0 || ($index > 0 && $index > $this->size - 1)) {
            throw new OutOfBoundsException();
        }

        // if the list is empty
        if($this->head === null) {
            return null;
        }
        
        // if only there is an element
        if($this->head->next === $this->head) {
            $temp = $this->head;
            $this->head = null;
            $this->size--;

            return $temp->data;
        }

        if($index === 0) {
            return $this->deleteBeginning();
        } else if($index === $this->size - 1) {
            return $this->deleteEnd();
        } else {
            return $this->deleteAt($index);
        }
    }

    /**
     * Deletes at the beginnig of the list and returns the data stored.
     *
     * @return mixed the data stored in the node.
     */
    private function deleteBeginning() {

        $temp = $this->head;
        $this->head = &$this->head->next;
        $this->tail->next = &$this->head;
        $this->size--;

        return $temp->data;
    }

    /**
     * Deletes at the specified position and returns the data stored.
     *
     * @param integer $index the position.
     * @return mixed the data stored in the node.
     */
    private function deleteAt($index) {
        $i = 0;
        $prev = $this->head;
        $current = $this->head;
        
        while($i < $index) {
            $prev = $current;
            $current = $current->next;
            $i++;
        }

        $temp = $current;
        $prev->next = &$current->next;
        $current->next->prev = &$pre;

        $current = null;
$myVar = 'Value';
$higher = false;

if (rand(1, 6) > 3) {
    $higher = true;
} else {
    $higher = false;
}
        $this->size--;

        return $temp->data;
    }

    /**
     * Deletes at the end of the list and returns the data stored.
     *
     * @return mixed the data stored in the node.
     */
    private function deleteEnd() {

        $prev = $this->head;
        $current = $this->head;
        
        while($current !== $this->tail) {
            $prev = $current;
            $current = $current->next;
        }
        
        $temp = $current;
        $prev->next = &$this->head;
        $this->head->prev = &$prev;
        $this->tail = &$prev;
        $current = null;
$myVar = 'Value';
$higher = false;

if (rand(1, 6) > 3) {
    $higher = true;
} else {
    $higher = false;
}

        $this->size--;

        return $temp->data;
    }
    
    /**
     * Converts/exports the list content into array type.
     *
     * @return array data stored in all nodes.
     */
    public function toArray() : array {
        $arr = [];
        foreach($this->getAll() as $node) {
            $arr[] = $node;
        }

        return $arr;
    }

    /**
     * Reset the cursor position.
     */
    public function rewind() {
        $this->position = 0;
        $this->current = &$this->head;
    }

    /**
     * Returns the current node data.
     *
     * @return mixed
     */
    public function current() {
        return $this->current->data;
    }

    /**
     * Key or index that indicates the cursor position.
     *
     * @return integer The current position.
     */
    public function key() {
        return $this->position;
    }

    /**
     * Move the cursor to the next node and increments the
     * position counter.
     */
    public function next() {
        ++$this->position;
        $this->current = $this->current->next;
    }

    /**
     * Returns if the current pointer position is valid.
     *
     * @return boolean true if pointer is not last, else false.
     */
    public function valid() {
        return $this->position < $this->size;
    }
}

1		<?php
2		/**
3		* DataStructures for PHP
4		*
5		* @link https://github.com/SiroDiaz/DataStructures
6		* @copyright Copyright (c) 2017 Siro Díaz Palazón
7		* @license https://github.com/SiroDiaz/DataStructures/blob/master/README.md (MIT License)
8		*/
9		namespace DataStructures\Lists;
10
11		use DataStructures\Lists\Traits\{CountTrait, ArrayAccessTrait};
12		use DataStructures\Lists\Nodes\DoublyLinkedListNode;
13		use DataStructures\Lists\ListAbstract;
14		use OutOfBoundsException;
15
16		/**
17		* DoublyLinkedList
18		*
19		* DoublyLinkedList is a double linked list that has
20		* a pointer to the next and the previous node.
21		*
22		* @author Siro Diaz Palazon <[email protected]>
23		*/
24		class DoublyLinkedList extends ListAbstract {
25		use ArrayAccessTrait;
26
27		private $head;
28		private $tail;
29		private $position;
30		private $current;
31
32	View Code Duplication	public function __construct() {
		0 ignored issues – show Duplication introduced 2017-06-05 14:14 UTC by Report Bug Copy Issue Report This method seems to be duplicated in your project. Duplicated code is one of the most pungent code smells. If you need to duplicate the same code in three or more different places, we strongly encourage you to look into extracting the code into a single class or operation. You can also find more detailed suggestions in the “Code” section of your repository. Loading history...
33		$this->head = null;
34		$this->tail = &$this->head;
35		$this->size = 0;
36		$this->position = 0;
37		$this->current = &$this->head;
38		}
39
40		/**
41		* Removes all nodes of the list. It removes from the beginning.
42		*/
43		public function clear() {
44		while($this->head !== null) {
45		$this->shift();
46		}
47		}
48
49		/**
50		* Gets the data stored in the position especified.
51		*
52		* @param integer $index Index that must be greater than 0
53		* and lower than the list size.
54		* @return mixed The data stored in the given index
55		* @throws OutOfBoundsException if index is out bounds.
56		*/
57	View Code Duplication	public function get($index) {
		0 ignored issues – show Duplication introduced 2017-06-24 20:15 UTC by Report Bug Copy Issue Report This method seems to be duplicated in your project. Duplicated code is one of the most pungent code smells. If you need to duplicate the same code in three or more different places, we strongly encourage you to look into extracting the code into a single class or operation. You can also find more detailed suggestions in the “Code” section of your repository. Loading history...
58		$node = $this->search($index);
59		if($node === null) {
60		return null;
61		}
62
63		return $node->data;
64		}
65
66		/**
67		* Gets the node stored in the position especified.
68		* If index is 0 or (size - 1) the method is O(1) else O(n).
69		*
70		* @param integer $index the position.
71		* @throws OutOfBoundsException if it is out of limits (< 0 or > size - 1)
72		* @return DataStructures\Lists\Nodes\DoublyLinkedListNode\|null the node stored in $index.
73		*/
74		protected function search($index) {
75		if($index < 0 \|\| $index > $this->size - 1) {
76		throw new OutOfBoundsException();
77		}
78
79		if($index === 0) {
80		return $this->head;
		0 ignored issues – show Bug Compatibility introduced 2017-06-24 14:29 UTC by Report Bug Copy Issue Report The expression `$this->head;` of type `null\|DataStructures\List...es\DoublyLinkedListNode` adds the type `DataStructures\Lists\Nodes\DoublyLinkedListNode` to the return on line 80 which is incompatible with the return type documented by `DataStructures\Lists\DoublyLinkedList::search` of type `DataStructures\Lists\Dat...ublyLinkedListNode\|null`. Loading history...
81		}
82
83		if($index === $this->size - 1) {
84		return $this->tail;
		0 ignored issues – show Bug Compatibility introduced 2017-06-24 14:29 UTC by Report Bug Copy Issue Report The expression `$this->tail;` of type `null\|DataStructures\List...es\DoublyLinkedListNode` adds the type `DataStructures\Lists\Nodes\DoublyLinkedListNode` to the return on line 84 which is incompatible with the return type documented by `DataStructures\Lists\DoublyLinkedList::search` of type `DataStructures\Lists\Dat...ublyLinkedListNode\|null`. Loading history...
85		}
86
87		$current = &$this->head;
88		if($index < (int) ceil($this->size / 2)) {
89		$i = 0;
90		while($i < $index) {
91		$current = &$current->next;
92		$i++;
93		}
94		} else {
95		$i = $this->size;
96		while($i > $index) {
97		$current = &$current->prev;
98		$i--;
99		}
100		}
101
102		return $current;
103		}
104
105		/**
106		* Returns the data in the last node with O(1).
107		*
108		* @return mixed null if the list is empty.
109		*/
110		public function getLast() {
111		if($this->head === null) {
112		return null;
113		}
114		return $this->tail->data;
115		}
116
117		/**
118		* Returns the last node with O(1).
119		*
120		* @return DataStructures\Lists\Nodes\DoublyLinkedListNode\|null if the list is empty.
121		*/
122		public function searchLast() {
123		if($this->head === null) {
124		return null;
125		}
126		return $this->tail;
127		}
128
129		/**
130		* {@inheritDoc}
131		*/
132		public function contains($data) : bool {
133		if($this->empty()) {
134		return false;
135		}
136
137		$current = $this->head->next;
138		$prev = $this->head;
139		while($current !== $this->head) {
140		if($prev->data === $data) {
141		return true;
142		}
143		$prev = $current;
144		$current = $current->next;
145		}
146
147		return false;
148		}
149
150		/**
151		* {@inheritDoc}
152		*/
153	View Code Duplication	public function indexOf($data) {
		0 ignored issues – show Duplication introduced 2017-07-08 23:51 UTC by Report Bug Copy Issue Report This method seems to be duplicated in your project. Duplicated code is one of the most pungent code smells. If you need to duplicate the same code in three or more different places, we strongly encourage you to look into extracting the code into a single class or operation. You can also find more detailed suggestions in the “Code” section of your repository. Loading history...
154		if($this->head === null) {
155		return false;
156		}
157
158		$current = $this->head;
159		$i = 0;
160
161		while($i < $this->size) {
162		if($current->data === $data) {
163		return $i;
164		}
165
166		$current = $current->next;
167		$i++;
168		}
169
170		return false;
171		}
172
173		/**
174		* {@inheritDoc}
175		*/
176	View Code Duplication	public function lastIndexOf($data) {
		0 ignored issues – show Duplication introduced 2017-07-09 14:20 UTC by Report Bug Copy Issue Report This method seems to be duplicated in your project. Duplicated code is one of the most pungent code smells. If you need to duplicate the same code in three or more different places, we strongly encourage you to look into extracting the code into a single class or operation. You can also find more detailed suggestions in the “Code” section of your repository. Loading history...
177		if($this->head === null) {
178		return false;
179		}
180
181		$current = $this->head;
182		$i = 0;
183		$pos = false;
184		while($i < $this->size) {
185		if($current->data == $data) {
186		$pos = $i;
187		}
188
189		$current = $current->next;
190		$i++;
191		}
192
193		return $pos;
194		}
195
196		/**
197		* {@inheritDoc}
198		*/
199		public function remove($data) {
200		$current = &$this->head;
201		$i = 0;
202
203		if($this->head === null) {
204		return null;
205		}
206
207		if($this->head->data === $data) {
208		$this->head = &$this->head->next;
209		$this->head->prev = &$this->tail;
210		$this->size--;
211
212		return $data;
213		}
214
215	View Code Duplication	while($i < $this->size) {
		0 ignored issues – show Duplication introduced 2017-07-13 14:42 UTC by Report Bug Copy Issue Report This code seems to be duplicated across your project. Duplicated code is one of the most pungent code smells. If you need to duplicate the same code in three or more different places, we strongly encourage you to look into extracting the code into a single class or operation. You can also find more detailed suggestions in the “Code” section of your repository. Loading history...
216		if($current->data === $data) {
217		$current->prev = &$current->next;
218		$current = null;
219		$this->size--;
220		return $data;
221		}
222
223		$current = $current->next;
224		}
225
226		return null;
227		}
228
229		/**
230		* Generator for retrieve all nodes stored.
231		*
232		* @return null if the head is null (or list is empty)
233		*/
234	View Code Duplication	public function getAll() {
		0 ignored issues – show Duplication introduced 2017-06-05 14:14 UTC by Report Bug Copy Issue Report This method seems to be duplicated in your project. Duplicated code is one of the most pungent code smells. If you need to duplicate the same code in three or more different places, we strongly encourage you to look into extracting the code into a single class or operation. You can also find more detailed suggestions in the “Code” section of your repository. Loading history...
235		if($this->head === null) {
236		return;
237		}
238
239		if($this->head === $this->tail) {
240		yield $this->head->data;
241		} else {
242		$current = $this->head;
243		$i = 0;
244		while($i < $this->size) {
245		yield $current->data;
246		$current = $current->next;
247		$i++;
248		}
249		}
250		}
251
252		/**
253		* Inserts at the beginning of the list.
254		*
255		* @param mixed $data
256		*/
257		protected function insertBeginning($data) {
258		$newNode = new DoublyLinkedListNode($data);
259		if($this->head === null) {
260		$newNode->next = &$this->head;
261		$newNode->prev = &$this->head;
262		$this->head = &$newNode;
263		$this->tail = &$newNode;
264		} else {
265		$this->tail->next = &$newNode;
266		$newNode->next = &$this->head;
267		$newNode->prev = &$this->tail;
268		$this->head = &$newNode;
269		}
270		}
271
272		/**
273		* Add a new node in the specified index.
274		*
275		* @param mixed $data the data to be stored.
276		*/
277		protected function insertEnd($data) {
278		$newNode = new DoublyLinkedListNode($data);
279		$this->tail->next = &$newNode;
280		$newNode->next = &$this->head;
281		$newNode->prev = &$this->tail;
282		$this->tail = &$newNode;
283		$this->head->prev = &$newNode;
284		}
285
286		/**
287		* Add a new node in the specified index.
288		*
289		* @param integer $index the position.
290		* @param mixed $data the data to be stored.
291		*/
292		protected function insertAt($index, $data) {
293		$newNode = new DoublyLinkedListNode($data);
294		$current = $this->head;
295		$prev = null;
296		$i = 0;
297		while($i < $index) {
298		$prev = $current;
299		$current = $current->next;
300		$i++;
301		}
302
303		$prev->next = &$newNode;
304		$newNode->prev = &$prev;
305		$newNode->next = &$current;
306		$current->prev = &$newNode;
307		}
308
309		/**
310		* Delete a node in the given position and returns it back.
311		*
312		* @param integer $index the position.
313		* @throws OutOfBoundsException if index is negative
314		* or is greater than the size of the list.
315		*/
316	View Code Duplication	public function delete($index) {
		0 ignored issues – show Duplication introduced 2017-06-05 14:14 UTC by Report Bug Copy Issue Report This method seems to be duplicated in your project. Duplicated code is one of the most pungent code smells. If you need to duplicate the same code in three or more different places, we strongly encourage you to look into extracting the code into a single class or operation. You can also find more detailed suggestions in the “Code” section of your repository. Loading history...
317		if($index < 0 \|\| ($index > 0 && $index > $this->size - 1)) {
318		throw new OutOfBoundsException();
319		}
320
321		// if the list is empty
322		if($this->head === null) {
323		return null;
324		}
325
326		// if only there is an element
327		if($this->head->next === $this->head) {
328		$temp = $this->head;
329		$this->head = null;
330		$this->size--;
331
332		return $temp->data;
333		}
334
335		if($index === 0) {
336		return $this->deleteBeginning();
337		} else if($index === $this->size - 1) {
338		return $this->deleteEnd();
339		} else {
340		return $this->deleteAt($index);
341		}
342		}
343
344		/**
345		* Deletes at the beginnig of the list and returns the data stored.
346		*
347		* @return mixed the data stored in the node.
348		*/
349	View Code Duplication	private function deleteBeginning() {
		0 ignored issues – show Duplication introduced 2017-06-05 14:14 UTC by Report Bug Copy Issue Report This method seems to be duplicated in your project. Duplicated code is one of the most pungent code smells. If you need to duplicate the same code in three or more different places, we strongly encourage you to look into extracting the code into a single class or operation. You can also find more detailed suggestions in the “Code” section of your repository. Loading history...
350		$temp = $this->head;
351		$this->head = &$this->head->next;
352		$this->tail->next = &$this->head;
353		$this->size--;
354
355		return $temp->data;
356		}
357
358		/**
359		* Deletes at the specified position and returns the data stored.
360		*
361		* @param integer $index the position.
362		* @return mixed the data stored in the node.
363		*/
364		private function deleteAt($index) {
365		$i = 0;
366		$prev = $this->head;
367		$current = $this->head;
368
369		while($i < $index) {
370		$prev = $current;
371		$current = $current->next;
372		$i++;
373		}
374
375		$temp = $current;
376		$prev->next = &$current->next;
377		$current->next->prev = &$pre;
		0 ignored issues – show Bug introduced 2017-06-05 14:14 UTC by Report Bug Copy Issue Report The variable `$pre` does not exist. Did you forget to declare it? This check marks access to variables or properties that have not been declared yet. While PHP has no explicit notion of declaring a variable, accessing it before a value is assigned to it is most likely a bug. Loading history...
378		$current = null;
		0 ignored issues – show Unused Code introduced 2017-06-05 14:14 UTC by Report Bug Copy Issue Report `$current` is not used, you could remove the assignment. This check looks for variable assignements that are either overwritten by other assignments or where the variable is not used subsequently. $myVar = 'Value'; $higher = false; if (rand(1, 6) > 3) { $higher = true; } else { $higher = false; } Both the `$myVar` assignment in line 1 and the `$higher` assignment in line 2 are dead. The first because `$myVar` is never used and the second because `$higher` is always overwritten for every possible time line. Loading history...
379		$this->size--;
380
381		return $temp->data;
382		}
383
384		/**
385		* Deletes at the end of the list and returns the data stored.
386		*
387		* @return mixed the data stored in the node.
388		*/
389	View Code Duplication	private function deleteEnd() {
		0 ignored issues – show Duplication introduced 2017-06-05 14:14 UTC by Report Bug Copy Issue Report This method seems to be duplicated in your project. Duplicated code is one of the most pungent code smells. If you need to duplicate the same code in three or more different places, we strongly encourage you to look into extracting the code into a single class or operation. You can also find more detailed suggestions in the “Code” section of your repository. Loading history...
390		$prev = $this->head;
391		$current = $this->head;
392
393		while($current !== $this->tail) {
394		$prev = $current;
395		$current = $current->next;
396		}
397
398		$temp = $current;
399		$prev->next = &$this->head;
400		$this->head->prev = &$prev;
401		$this->tail = &$prev;
402		$current = null;
		0 ignored issues – show Unused Code introduced 2017-06-05 14:14 UTC by Report Bug Copy Issue Report `$current` is not used, you could remove the assignment. This check looks for variable assignements that are either overwritten by other assignments or where the variable is not used subsequently. $myVar = 'Value'; $higher = false; if (rand(1, 6) > 3) { $higher = true; } else { $higher = false; } Both the `$myVar` assignment in line 1 and the `$higher` assignment in line 2 are dead. The first because `$myVar` is never used and the second because `$higher` is always overwritten for every possible time line. Loading history...
403
404		$this->size--;
405
406		return $temp->data;
407		}
408
409		/**
410		* Converts/exports the list content into array type.
411		*
412		* @return array data stored in all nodes.
413		*/
414		public function toArray() : array {
415		$arr = [];
416		foreach($this->getAll() as $node) {
417		$arr[] = $node;
418		}
419
420		return $arr;
421		}
422
423		/**
424		* Reset the cursor position.
425		*/
426		public function rewind() {
427		$this->position = 0;
428		$this->current = &$this->head;
429		}
430
431		/**
432		* Returns the current node data.
433		*
434		* @return mixed
435		*/
436		public function current() {
437		return $this->current->data;
438		}
439
440		/**
441		* Key or index that indicates the cursor position.
442		*
443		* @return integer The current position.
444		*/
445		public function key() {
446		return $this->position;
447		}
448
449		/**
450		* Move the cursor to the next node and increments the
451		* position counter.
452		*/
453		public function next() {
454		++$this->position;
455		$this->current = $this->current->next;
456		}
457
458		/**
459		* Returns if the current pointer position is valid.
460		*
461		* @return boolean true if pointer is not last, else false.
462		*/
463		public function valid() {
464		return $this->position < $this->size;
465		}
466		}

SiroDiaz / DataStructures