TreeNode::getResultSubject()   A
last analyzed

Complexity

Conditions 2
Paths 2

Size

Total Lines 10

Duplication

Lines 0
Ratio 0 %

Code Coverage

Tests 5
CRAP Score 2

Importance

Changes 0
Metric Value
dl 0
loc 10
ccs 5
cts 5
cp 1
rs 9.9332
c 0
b 0
f 0
cc 2
nc 2
nop 0
crap 2
1
<?php
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namespace SRF\Formats\Tree;
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use Cdb\Exception;
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use Tree\Node\Node;
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use Tree\Node\NodeInterface;
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use Tree\Node\NodeTrait;
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class TreeNode extends Node {
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	/**
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	 * SRFTreeElement constructor.
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	 *
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	 * @param \SMWResultArray[] | null $row
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	 */
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	public function __construct( $row = null ) {
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		parent::__construct( $row );
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	}
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	/**
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	 * @return string
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	 */
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	public function getHash() {
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		$resultSubject = $this->getResultSubject();
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		if ( $resultSubject !== null ) {
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			return $resultSubject->getSerialization();
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		}
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		return '';
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	}
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	/**
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	 * @return null|\SMWDIWikiPage
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	 */
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	public function getResultSubject() {
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		/** @var \SMWResultArray[] | null $row */
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		$row = $this->getValue();
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		if ( $row !== null ) {
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			return $row[0]->getResultSubject();
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		}
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		return null;
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	}
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	/**
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	 * @param NodeInterface $child
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	 *
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	 * @return NodeTrait
0 ignored issues
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Comprehensibility Bug introduced by Stephan Gambke
The return type NodeTrait is a trait, and thus cannot be used for type-hinting in PHP. Maybe consider adding an interface and use that for type-hinting?

In PHP traits cannot be used for type-hinting as they do not define a well-defined structure. This is because any class that uses a trait can rename that trait’s methods.

If you would like to return an object that has a guaranteed set of methods, you could create a companion interface that lists these methods explicitly.

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	 * @throws Exception
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	 */
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	public function addChild( NodeInterface $child ) {
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		foreach ( $this->getAncestorsAndSelf() as $ancestor ) {
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			if ( $ancestor->getHash() === $child->getHash() ) {
0 ignored issues
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Bug introduced by Stephan Gambke
It seems like you code against a concrete implementation and not the interface Tree\Node\NodeInterface as the method getHash() does only exist in the following implementations of said interface: SRF\Formats\Tree\TreeNode.

Let’s take a look at an example:

interface User
{
    /** @return string */
    public function getPassword();
}

class MyUser implements User
{
    public function getPassword()
    {
        // return something
    }

    public function getDisplayName()
    {
        // return some name.
    }
}

class AuthSystem
{
    public function authenticate(User $user)
    {
        $this->logger->info(sprintf('Authenticating %s.', $user->getDisplayName()));
        // do something.
    }
}

In the above example, the authenticate() method works fine as long as you just pass instances of MyUser. However, if you now also want to pass a different implementation of User which does not have a getDisplayName() method, the code will break.

Available Fixes

  1. Change the type-hint for the parameter:

    class AuthSystem
    {
        public function authenticate(MyUser $user) { /* ... */ }
    }
    
  2. Add an additional type-check:

    class AuthSystem
    {
        public function authenticate(User $user)
        {
            if ($user instanceof MyUser) {
                $this->logger->info(/** ... */);
            }
    
            // or alternatively
            if ( ! $user instanceof MyUser) {
                throw new \LogicException(
                    '$user must be an instance of MyUser, '
                   .'other instances are not supported.'
                );
            }
    
        }
    }
    
Note: PHP Analyzer uses reverse abstract interpretation to narrow down the types inside the if block in such a case.
  1. Add the method to the interface:

    interface User
    {
        /** @return string */
        public function getPassword();
    
        /** @return string */
        public function getDisplayName();
    }
    
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59 1
				throw new Exception( 'srf-tree-circledetected' );
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			}
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		}
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		return parent::addChild( $child );
0 ignored issues
show
Bug Best Practice introduced by Stephan Gambke
The return type of return parent::addChild($child); (SRF\Formats\Tree\TreeNode) is incompatible with the return type of the parent method Tree\Node\Node::addChild of type Tree\Node\NodeTrait.

If you return a value from a function or method, it should be a sub-type of the type that is given by the parent type f.e. an interface, or abstract method. This is more formally defined by the Lizkov substitution principle, and guarantees that classes that depend on the parent type can use any instance of a child type interchangably. This principle also belongs to the SOLID principles for object oriented design.

Let’s take a look at an example:

class Author {
    private $name;

    public function __construct($name) {
        $this->name = $name;
    }

    public function getName() {
        return $this->name;
    }
}

abstract class Post {
    public function getAuthor() {
        return 'Johannes';
    }
}

class BlogPost extends Post {
    public function getAuthor() {
        return new Author('Johannes');
    }
}

class ForumPost extends Post { /* ... */ }

function my_function(Post $post) {
    echo strtoupper($post->getAuthor());
}

Our function my_function expects a Post object, and outputs the author of the post. The base class Post returns a simple string and outputting a simple string will work just fine. However, the child class BlogPost which is a sub-type of Post instead decided to return an object, and is therefore violating the SOLID principles. If a BlogPost were passed to my_function, PHP would not complain, but ultimately fail when executing the strtoupper call in its body.

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	}
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}
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