| 1 |  |  | <?php | 
            
                                                                                                            
                            
            
                                    
            
            
                | 2 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 3 |  |  | namespace Dazzle\Promise; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 4 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 5 |  |  | use Dazzle\Promise\Partial\PromiseTrait; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 6 |  |  | use Error; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 7 |  |  | use Exception; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 8 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 9 |  |  | class Promise implements PromiseInterface | 
            
                                                                                                            
                            
            
                                    
            
            
                | 10 |  |  | { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 11 |  |  |     use PromiseTrait; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 12 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 13 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 14 |  |  |      * @var PromiseInterface|null | 
            
                                                                                                            
                            
            
                                    
            
            
                | 15 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 16 |  |  |     protected $result; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 17 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 18 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 19 |  |  |      * @var callable[] | 
            
                                                                                                            
                            
            
                                    
            
            
                | 20 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 21 |  |  |     protected $handlers; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 22 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 23 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 24 |  |  |      * @var callable | 
            
                                                                                                            
                            
            
                                    
            
            
                | 25 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 26 |  |  |     protected $canceller; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 27 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 28 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 29 |  |  |      * @var int | 
            
                                                                                                            
                            
            
                                    
            
            
                | 30 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 31 |  |  |     protected $currentCancellations; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 32 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 33 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 34 |  |  |      * @var int | 
            
                                                                                                            
                            
            
                                    
            
            
                | 35 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 36 |  |  |     protected $requiredCancellations; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 37 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 38 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 39 |  |  |      * @param callable|null $resolver | 
            
                                                                                                            
                            
            
                                    
            
            
                | 40 |  |  |      * @param callable|null $canceller | 
            
                                                                                                            
                            
            
                                    
            
            
                | 41 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 42 | 374 |  |     public function __construct(callable $resolver = null, callable $canceller = null) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 43 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 44 | 374 |  |         $this->result = null; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 45 | 374 |  |         $this->handlers = []; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 46 |  |  |         $this->canceller = function($reason = null) use($canceller) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 47 |  |  |             try | 
            
                                                                                                            
                            
            
                                    
            
            
                | 48 |  |  |             { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 49 | 108 |  |                 return $canceller !== null && ($result = $canceller($reason)) instanceof self ? $result : $this; | 
                            
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                | 50 |  |  |             } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 51 |  |  |             catch (Error $ex) | 
                            
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                | 52 |  |  |             {} | 
            
                                                                                                            
                            
            
                                    
            
            
                | 53 |  |  |             catch (Exception $ex) | 
                            
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                | 54 |  |  |             {} | 
            
                                                                                                            
                            
            
                                    
            
            
                | 55 |  |  |             return $this; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 56 |  |  |         }; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 57 | 374 |  |         $this->currentCancellations = 0; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 58 | 374 |  |         $this->requiredCancellations = 0; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 59 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 60 | 374 |  |         $this->mutate($resolver); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 61 | 374 |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 62 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 63 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 64 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 65 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 66 | 103 |  |     public function __destruct() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 67 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 68 | 103 |  |         unset($this->result); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 69 | 103 |  |         unset($this->handlers); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 70 | 103 |  |         unset($this->canceller); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 71 | 103 |  |         unset($this->currentCancellations); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 72 | 103 |  |         unset($this->requiredCancellations); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 73 | 103 |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 74 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 75 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 76 |  |  |      * @override | 
            
                                                                                                            
                            
            
                                    
            
            
                | 77 |  |  |      * @inheritDoc | 
            
                                                                                                            
                            
            
                                    
            
            
                | 78 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 79 | 222 |  |     public function then(callable $onFulfilled = null, callable $onRejected = null, callable $onCancel = null) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 80 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 81 | 222 |  |         if (null !== $this->result) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 82 |  |  |         { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 83 | 130 |  |             return $this->getResult()->then($onFulfilled, $onRejected, $onCancel); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 84 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 85 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 86 | 96 |  |         if (null !== $this->canceller) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 87 |  |  |         { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 88 | 96 |  |             $this->requiredCancellations++; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 89 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 90 |  |  |             $canceller = function($reason = null) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 91 | 39 |  |                 if (++$this->currentCancellations >= $this->requiredCancellations) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 92 |  |  |                 { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 93 | 35 |  |                     return $this->cancel($reason); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 94 |  |  |                 } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 95 | 12 |  |                 return null; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 96 | 96 |  |             }; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 97 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 98 |  |  |         else | 
            
                                                                                                            
                            
            
                                    
            
            
                | 99 |  |  |         { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 100 |  |  |             $canceller = null; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 101 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 102 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 103 |  |  |         return new static(function($resolve, $reject, $cancel) use($onFulfilled, $onRejected, $onCancel) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 104 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 105 |  |  |             $this->handlers[] = function(PromiseInterface $promise) use($resolve, $reject, $cancel, $onFulfilled, $onRejected, $onCancel) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 106 |  |  |                 $promise | 
            
                                                                                                            
                            
            
                                    
            
            
                | 107 | 86 |  |                     ->then($onFulfilled, $onRejected, $onCancel) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 108 | 86 |  |                     ->done($resolve, $reject, $cancel) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 109 |  |  |                 ; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 110 | 84 |  |             }; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 111 | 96 |  |         }, $canceller); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 112 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 113 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 114 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 115 |  |  |      * @override | 
            
                                                                                                            
                            
            
                                    
            
            
                | 116 |  |  |      * @inheritDoc | 
            
                                                                                                            
                                                                
            
                                    
            
            
                | 117 |  |  |      */ | 
            
                                                                        
                            
            
                                    
            
            
                | 118 | 80 |  |     public function done(callable $onFulfilled = null, callable $onRejected = null, callable $onCancel = null) | 
            
                                                                        
                            
            
                                    
            
            
                | 119 |  |  |     { | 
            
                                                                        
                            
            
                                    
            
            
                | 120 | 80 |  |         if (null !== $this->result) | 
            
                                                                        
                            
            
                                    
            
            
                | 121 |  |  |         { | 
            
                                                                        
                            
            
                                    
            
            
                | 122 | 39 |  |             $this->getResult()->done($onFulfilled, $onRejected, $onCancel); | 
            
                                                                        
                            
            
                                    
            
            
                | 123 |  |  |         } | 
            
                                                                        
                            
            
                                    
            
            
                | 124 |  |  |  | 
            
                                                                        
                            
            
                                    
            
            
                | 125 |  |  |         $this->handlers[] = function(PromiseInterface $promise) use($onFulfilled, $onRejected, $onCancel) { | 
            
                                                                        
                            
            
                                    
            
            
                | 126 |  |  |             $promise | 
            
                                                                        
                            
            
                                    
            
            
                | 127 | 37 |  |                 ->done($onFulfilled, $onRejected, $onCancel); | 
            
                                                                        
                            
            
                                    
            
            
                | 128 | 17 |  |         }; | 
            
                                                                        
                            
            
                                    
            
            
                | 129 | 54 |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 130 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 131 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 132 |  |  |      * @override | 
            
                                                                                                            
                            
            
                                    
            
            
                | 133 |  |  |      * @inheritDoc | 
            
                                                                                                            
                            
            
                                    
            
            
                | 134 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 135 | 18 |  |     public function spread(callable $onFulfilled = null, callable $onRejected = null, callable $onCancel = null) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 136 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 137 | 18 |  |         return $this->then( | 
            
                                                                                                            
                            
            
                                    
            
            
                | 138 |  |  |             function($values) use($onFulfilled) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 139 | 6 |  |                 return $onFulfilled(...((array) $values)); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 140 | 18 |  |             }, | 
            
                                                                                                            
                            
            
                                    
            
            
                | 141 |  |  |             function($rejections) use($onRejected) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 142 | 6 |  |                 return $onRejected(...((array) $rejections)); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 143 | 18 |  |             }, | 
            
                                                                                                            
                            
            
                                    
            
            
                | 144 |  |  |             function($reasons) use($onCancel) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 145 | 6 |  |                 return $onCancel(...((array) $reasons)); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 146 | 18 |  |             } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 147 |  |  |         ); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 148 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 149 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 150 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 151 |  |  |      * @override | 
            
                                                                                                            
                            
            
                                    
            
            
                | 152 |  |  |      * @inheritDoc | 
            
                                                                                                            
                            
            
                                    
            
            
                | 153 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 154 | 8 |  |     public function success(callable $onSuccess) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 155 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 156 | 8 |  |         return $this->then($onSuccess); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 157 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 158 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 159 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 160 |  |  |      * @override | 
            
                                                                                                            
                            
            
                                    
            
            
                | 161 |  |  |      * @inheritDoc | 
            
                                                                                                            
                            
            
                                    
            
            
                | 162 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 163 | 10 |  |     public function failure(callable $onFailure) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 164 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 165 | 10 |  |         return $this->then(null, $onFailure); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 166 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 167 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 168 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 169 |  |  |      * @override | 
            
                                                                                                            
                            
            
                                    
            
            
                | 170 |  |  |      * @inheritDoc | 
            
                                                                                                            
                            
            
                                    
            
            
                | 171 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 172 | 8 |  |     public function abort(callable $onCancel) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 173 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 174 | 8 |  |         return $this->then(null, null, $onCancel); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 175 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 176 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 177 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 178 |  |  |      * @override | 
            
                                                                                                            
                            
            
                                    
            
            
                | 179 |  |  |      * @inheritDoc | 
            
                                                                                                            
                            
            
                                    
            
            
                | 180 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 181 | 58 |  |     public function always(callable $onFulfilledOrRejected) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 182 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 183 | 58 |  |         return $this->then( | 
            
                                                                                                            
                            
            
                                    
            
            
                | 184 |  |  |             function($value) use($onFulfilledOrRejected) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 185 |  |  |                 return self::doResolve($onFulfilledOrRejected())->then(function() use($value) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 186 | 12 |  |                     return $value; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 187 | 16 |  |                 }); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 188 | 58 |  |             }, | 
            
                                                                                                            
                            
            
                                    
            
            
                | 189 |  |  |             function($reason) use($onFulfilledOrRejected) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 190 |  |  |                 return self::doResolve($onFulfilledOrRejected())->then(function() use($reason) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 191 | 12 |  |                     return new PromiseRejected($reason); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 192 | 16 |  |                 }); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 193 | 58 |  |             }, | 
            
                                                                                                            
                            
            
                                    
            
            
                | 194 |  |  |             function($reason) use($onFulfilledOrRejected) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 195 |  |  |                 return self::doResolve($onFulfilledOrRejected())->then(function() use($reason) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 196 | 12 |  |                     return new PromiseCancelled($reason); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 197 | 14 |  |                 }); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 198 | 58 |  |             } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 199 |  |  |         ); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 200 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 201 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 202 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 203 |  |  |      * @override | 
            
                                                                                                            
                            
            
                                    
            
            
                | 204 |  |  |      * @inheritDoc | 
            
                                                                                                            
                            
            
                                    
            
            
                | 205 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 206 | 34 |  |     public function isPending() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 207 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 208 | 34 |  |         return $this->result === null; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 209 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 210 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 211 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 212 |  |  |      * @override | 
            
                                                                                                            
                            
            
                                    
            
            
                | 213 |  |  |      * @inheritDoc | 
            
                                                                                                            
                            
            
                                    
            
            
                | 214 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 215 | 8 |  |     public function isFulfilled() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 216 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 217 | 8 |  |         return !$this->isPending() && $this->result->isFulfilled(); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 218 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 219 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 220 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 221 |  |  |      * @override | 
            
                                                                                                            
                            
            
                                    
            
            
                | 222 |  |  |      * @inheritDoc | 
            
                                                                                                            
                            
            
                                    
            
            
                | 223 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 224 | 8 |  |     public function isRejected() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 225 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 226 | 8 |  |         return !$this->isPending() && $this->result->isRejected(); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 227 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 228 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 229 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 230 |  |  |      * @override | 
            
                                                                                                            
                            
            
                                    
            
            
                | 231 |  |  |      * @inheritDoc | 
            
                                                                                                            
                            
            
                                    
            
            
                | 232 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 233 | 10 |  |     public function isCancelled() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 234 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 235 | 10 |  |         return !$this->isPending() && $this->result->isCancelled(); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 236 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 237 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 238 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 239 |  |  |      * @override | 
            
                                                                                                            
                            
            
                                    
            
            
                | 240 |  |  |      * @inheritDoc | 
            
                                                                                                            
                            
            
                                    
            
            
                | 241 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 242 |  |  |     public function getPromise() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 243 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 244 |  |  |         return $this; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 245 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 246 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 247 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 248 |  |  |      * @override | 
            
                                                                                                            
                            
            
                                    
            
            
                | 249 |  |  |      * @inheritDoc | 
            
                                                                                                            
                            
            
                                    
            
            
                | 250 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 251 | 144 |  |     public function resolve($value = null) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 252 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 253 | 144 |  |         if (null !== $this->result || $value === $this) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 254 |  |  |         { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 255 | 10 |  |             return $this->result; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 256 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 257 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 258 | 142 |  |         return $this->settle(self::doResolve($value)); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 259 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 260 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 261 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 262 |  |  |      * @override | 
            
                                                                                                            
                            
            
                                    
            
            
                | 263 |  |  |      * @inheritDoc | 
            
                                                                                                            
                            
            
                                    
            
            
                | 264 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 265 | 114 |  |     public function reject($reason = null) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 266 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 267 | 114 |  |         if (null !== $this->result || $reason === $this) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 268 |  |  |         { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 269 | 6 |  |             return $this->result; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 270 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 271 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 272 | 112 |  |         return $this->settle(self::doReject($reason)); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 273 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 274 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 275 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 276 |  |  |      * @override | 
            
                                                                                                            
                            
            
                                    
            
            
                | 277 |  |  |      * @inheritDoc | 
            
                                                                                                            
                            
            
                                    
            
            
                | 278 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 279 | 121 |  |     public function cancel($reason = null) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 280 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 281 | 121 |  |         if (null !== $this->result || $reason === $this) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 282 |  |  |         { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 283 | 50 |  |             return $this->result; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 284 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 285 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 286 | 108 |  |         $target = $this; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 287 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 288 | 108 |  |         if (null !== $this->canceller) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 289 |  |  |         { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 290 | 108 |  |             $canceller = $this->canceller; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 291 | 108 |  |             $this->canceller = null; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 292 | 108 |  |             $target = $canceller($reason); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 293 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 294 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 295 | 108 |  |         if ($target === $this) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 296 |  |  |         { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 297 | 108 |  |             return $target->settle(self::doCancel($reason)); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 298 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 299 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 300 |  |  |         return $target; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 301 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 302 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 303 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 304 |  |  |      * Return primitive value associated with Promise. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 305 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 306 |  |  |      * @return mixed|null | 
            
                                                                                                            
                            
            
                                    
            
            
                | 307 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 308 |  |  |     protected function getValue() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 309 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 310 |  |  |         return $this->isFulfilled() ? $this->result->getValue() : null; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 311 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 312 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 313 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 314 |  |  |      * Return rejection or cancellation reason for Promise. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 315 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 316 |  |  |      * @return Error|Exception|string|null | 
            
                                                                                                            
                            
            
                                    
            
            
                | 317 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 318 |  |  |     protected function getReason() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 319 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 320 |  |  |         return ($this->isRejected() || $this->isCancelled()) ? $this->result->getReason() : null; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 321 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 322 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 323 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 324 |  |  |      * Settle Promise with another Promise. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 325 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 326 |  |  |      * @see PromiseInterface::resolve | 
            
                                                                                                            
                            
            
                                    
            
            
                | 327 |  |  |      * @see PromiseInterface::reject | 
            
                                                                                                            
                            
            
                                    
            
            
                | 328 |  |  |      * @see PromiseInterface::cancel | 
            
                                                                                                            
                            
            
                                    
            
            
                | 329 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 330 |  |  |      * @param PromiseInterface $promise | 
            
                                                                                                            
                            
            
                                    
            
            
                | 331 |  |  |      * @return PromiseInterface | 
            
                                                                                                            
                            
            
                                    
            
            
                | 332 |  |  |      * @resolves mixed|null | 
            
                                                                                                            
                            
            
                                    
            
            
                | 333 |  |  |      * @rejects Error|Exception|string|null | 
            
                                                                                                            
                            
            
                                    
            
            
                | 334 |  |  |      * @cancels Error|Exception|string|null | 
            
                                                                                                            
                            
            
                                    
            
            
                | 335 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 336 | 330 |  |     protected function settle(PromiseInterface $promise) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 337 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 338 | 330 |  |         $handlers = $this->handlers; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 339 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 340 | 330 |  |         $this->result = $promise; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 341 | 330 |  |         $this->handlers = []; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 342 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 343 | 330 |  |         foreach ($handlers as $handler) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 344 |  |  |         { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 345 | 114 |  |             $handler($promise); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 346 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 347 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 348 | 312 |  |         return $promise; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 349 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 350 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 351 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 352 |  |  |      * Get Promise result. Returns fulfilled, rejected or cancelled Promise for settled Promises or null for pending. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 353 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 354 |  |  |      * @return PromiseInterface|null | 
            
                                                                                                            
                            
            
                                    
            
            
                | 355 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 356 | 168 |  |     protected function getResult() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 357 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 358 | 168 |  |         while ($this->result instanceof Promise && null !== $this->result->result) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 359 |  |  |         { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 360 | 1 |  |             $this->result = $this->result->result; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 361 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 362 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 363 | 168 |  |         return $this->result; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 364 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 365 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 366 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 367 |  |  |      * Mutate resolver. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 368 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 369 |  |  |      * @param callable|null $resolver | 
            
                                                                                                            
                            
            
                                    
            
            
                | 370 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 371 | 374 |  |     protected function mutate(callable $resolver = null) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 372 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 373 | 374 |  |         if ($resolver === null) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 374 |  |  |         { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 375 | 24 |  |             return; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 376 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 377 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 378 |  |  |         try | 
            
                                                                                                            
                            
            
                                    
            
            
                | 379 |  |  |         { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 380 | 350 |  |             $resolver( | 
            
                                                                                                            
                            
            
                                    
            
            
                | 381 |  |  |                 function ($value = null) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 382 | 140 |  |                     $this->resolve($value); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 383 | 350 |  |                 }, | 
            
                                                                                                            
                            
            
                                    
            
            
                | 384 |  |  |                 function ($reason = null) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 385 | 106 |  |                     $this->reject($reason); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 386 | 350 |  |                 }, | 
            
                                                                                                            
                            
            
                                    
            
            
                | 387 | 350 |  |                 function ($reason = null) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 388 | 98 |  |                     $this->cancel($reason); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 389 | 350 |  |                 } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 390 |  |  |             ); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 391 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 392 | 4 |  |         catch (Error $ex) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 393 |  |  |         { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 394 |  |  |             $this->reject($ex); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 395 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 396 | 4 |  |         catch (Exception $ex) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 397 |  |  |         { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 398 | 4 |  |             $this->reject($ex); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 399 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 400 | 350 |  |     } | 
            
                                                                                                            
                                                                
            
                                    
            
            
                | 401 |  |  | } | 
            
                                                        
            
                                    
            
            
                | 402 |  |  |  | 
            
                        
If you define a variable conditionally, it can happen that it is not defined for all execution paths.
Let’s take a look at an example:
In the above example, the variable $x is defined if you pass “foo” or “bar” as argument for $a. However, since the switch statement has no default case statement, if you pass any other value, the variable $x would be undefined.
Available Fixes
Check for existence of the variable explicitly:
Define a default value for the variable:
Add a value for the missing path: