| 1 |  |  | <?php | 
            
                                                                                                            
                            
            
                                    
            
            
                | 2 |  |  | /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 3 |  |  |  * This file is part of graze/data-file | 
            
                                                                                                            
                            
            
                                    
            
            
                | 4 |  |  |  * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 5 |  |  |  * Copyright (c) 2016 Nature Delivered Ltd. <https://www.graze.com> | 
            
                                                                                                            
                            
            
                                    
            
            
                | 6 |  |  |  * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 7 |  |  |  * For the full copyright and license information, please view the LICENSE | 
            
                                                                                                            
                            
            
                                    
            
            
                | 8 |  |  |  * file that was distributed with this source code. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 9 |  |  |  * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 10 |  |  |  * @license https://github.com/graze/data-file/blob/master/LICENSE.md | 
            
                                                                                                            
                            
            
                                    
            
            
                | 11 |  |  |  * @link    https://github.com/graze/data-file | 
            
                                                                                                            
                            
            
                                    
            
            
                | 12 |  |  |  */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 13 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 14 |  |  | namespace Graze\DataFile\Node; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 15 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 16 |  |  | use Graze\DataFile\Format\FormatAwareInterface; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 17 |  |  | use Graze\DataFile\Format\FormatAwareTrait; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 18 |  |  | use Graze\DataFile\Modify\Compress\CompressionAwareInterface; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 19 |  |  | use Graze\DataFile\Modify\Compress\CompressionAwareTrait; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 20 |  |  | use Graze\DataFile\Modify\Encoding\EncodingAwareInterface; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 21 |  |  | use Graze\DataFile\Modify\Encoding\EncodingAwareTrait; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 22 |  |  | use Graze\DataFile\Modify\Exception\CopyFailedException; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 23 |  |  | use Graze\DataFile\Node\FileSystem\FilesystemWrapper; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 24 |  |  | use Graze\DataFile\Node\FileSystem\FileSystemWrapperInterface; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 25 |  |  | use League\Flysystem\File; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 26 |  |  | use League\Flysystem\FilesystemInterface; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 27 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 28 |  |  | class FileNode extends File implements FileNodeInterface, FormatAwareInterface, CompressionAwareInterface, EncodingAwareInterface | 
            
                                                                                                            
                            
            
                                    
            
            
                | 29 |  |  | { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 30 |  |  |     use FormatAwareTrait; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 31 |  |  |     use CompressionAwareTrait; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 32 |  |  |     use EncodingAwareTrait; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 33 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 34 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 35 |  |  |      * FileNode constructor. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 36 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 37 |  |  |      * @param FilesystemInterface $filesystem | 
            
                                                                                                            
                            
            
                                    
            
            
                | 38 |  |  |      * @param null|string         $path | 
            
                                                                                                            
                                                                
            
                                    
            
            
                | 39 |  |  |      */ | 
            
                                                                        
                            
            
                                    
            
            
                | 40 | 112 |  |     public function __construct(FilesystemInterface $filesystem, $path) | 
            
                                                                        
                            
            
                                    
            
            
                | 41 |  |  |     { | 
            
                                                                        
                            
            
                                    
            
            
                | 42 | 112 |  |         $wrapper = new FilesystemWrapper($filesystem); | 
            
                                                                        
                            
            
                                    
            
            
                | 43 | 112 |  |         parent::__construct($wrapper, $path); | 
            
                                                                        
                            
            
                                    
            
            
                | 44 | 112 |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 45 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 46 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 47 |  |  |      * @return string | 
            
                                                                                                            
                            
            
                                    
            
            
                | 48 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 49 | 14 |  |     public function __toString() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 50 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 51 | 14 |  |         return $this->getPath(); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 52 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 53 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 54 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 55 |  |  |      * @return mixed | 
            
                                                                                                            
                            
            
                                    
            
            
                | 56 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 57 | 10 |  |     public function getDirectory() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 58 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 59 | 10 |  |         return pathinfo($this->path, PATHINFO_DIRNAME) . '/'; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 60 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 61 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 62 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 63 |  |  |      * @return string | 
            
                                                                                                            
                            
            
                                    
            
            
                | 64 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 65 | 18 |  |     public function getFilename() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 66 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 67 | 18 |  |         return pathinfo($this->path, PATHINFO_BASENAME); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 68 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 69 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 70 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 71 |  |  |      * Returns the contents of the file as an array. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 72 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 73 |  |  |      * @return array | 
            
                                                                                                            
                            
            
                                    
            
            
                | 74 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 75 | 21 |  |     public function getContents() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 76 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 77 | 21 |  |         if ($this->exists()) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 78 | 19 |  |             return explode("\n", trim($this->read())); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 79 |  |  |         } else { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 80 | 2 |  |             return []; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 81 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 82 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 83 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 84 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 85 |  |  |      * @param string|null $newPath | 
            
                                                                                                            
                            
            
                                    
            
            
                | 86 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 87 |  |  |      * @return static | 
            
                                                                                                            
                            
            
                                    
            
            
                | 88 |  |  |      * @throws CopyFailedException When it is unable to copy the file | 
            
                                                                                                            
                            
            
                                    
            
            
                | 89 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 90 | 4 |  |     public function copy($newPath = null) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 91 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 92 | 4 |  |         if (is_null($newPath)) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 93 | 1 |  |             $newPath = $this->path . '-copy'; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 94 | 1 |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 95 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 96 | 4 |  |         if (@$this->filesystem->copy($this->path, $newPath)) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 97 | 3 |  |             return $this->getClone()->setPath($newPath); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 98 |  |  |         } else { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 99 | 1 |  |             $lastError = error_get_last(); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 100 | 1 |  |             throw new CopyFailedException($this, $newPath, $lastError['message']); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 101 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 102 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 103 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 104 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 105 |  |  |      * @return FileSystemWrapperInterface | 
            
                                                                                                            
                            
            
                                    
            
            
                | 106 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 107 | 16 |  |     public function getFilesystem() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 108 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 109 | 16 |  |         return parent::getFilesystem(); | 
                            
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                | 110 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 111 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 112 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 113 |  |  |      * Return a clone of this object | 
            
                                                                                                            
                            
            
                                    
            
            
                | 114 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 115 |  |  |      * @return static | 
            
                                                                                                            
                            
            
                                    
            
            
                | 116 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 117 | 57 |  |     public function getClone() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 118 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 119 | 57 |  |         return clone $this; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 120 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 121 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 122 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 123 |  |  |      * Clone sub objects | 
            
                                                                                                            
                            
            
                                    
            
            
                | 124 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 125 | 57 |  |     public function __clone() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 126 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 127 | 57 |  |         if ($this->format) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 128 | 1 |  |             $this->format = clone $this->format; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 129 | 1 |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 130 | 57 |  |     } | 
            
                                                                                                            
                                                                
            
                                    
            
            
                | 131 |  |  | } | 
            
                                                        
            
                                    
            
            
                | 132 |  |  |  | 
            
                        
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:
Our function
my_functionexpects aPostobject, and outputs the author of the post. The base classPostreturns a simple string and outputting a simple string will work just fine. However, the child classBlogPostwhich is a sub-type ofPostinstead decided to return anobject, and is therefore violating the SOLID principles. If aBlogPostwere passed tomy_function, PHP would not complain, but ultimately fail when executing thestrtouppercall in its body.