Complex classes like ReflectionClassLikeTrait often do a lot of different things. To break such a class down, we need to identify a cohesive component within that class. A common approach to find such a component is to look for fields/methods that share the same prefixes, or suffixes. You can also have a look at the cohesion graph to spot any un-connected, or weakly-connected components.
Once you have determined the fields that belong together, you can apply the Extract Class refactoring. If the component makes sense as a sub-class, Extract Subclass is also a candidate, and is often faster.
While breaking up the class, it is a good idea to analyze how other classes use ReflectionClassLikeTrait, and based on these observations, apply Extract Interface, too.
| 1 | <?php |
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| 30 | trait ReflectionClassLikeTrait |
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| 31 | { |
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| 32 | use InitializationTrait; |
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| 33 | |||
| 34 | /** |
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| 35 | * @var ClassLike |
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| 36 | */ |
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| 37 | protected $classLikeNode; |
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| 38 | |||
| 39 | /** |
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| 40 | * Short name of the class, without namespace |
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| 41 | * |
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| 42 | * @var string |
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| 43 | */ |
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| 44 | protected $className; |
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| 45 | |||
| 46 | /** |
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| 47 | * List of all constants from the class |
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| 48 | * |
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| 49 | * @var array |
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| 50 | */ |
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| 51 | protected $constants; |
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| 52 | |||
| 53 | /** |
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| 54 | * Interfaces, empty array or null if not initialized yet |
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| 55 | * |
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| 56 | * @var \ReflectionClass[]|array|null |
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| 57 | */ |
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| 58 | protected $interfaceClasses; |
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| 59 | |||
| 60 | /** |
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| 61 | * List of traits, empty array or null if not initialized yet |
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| 62 | * |
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| 63 | * @var \ReflectionClass[]|array|null |
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| 64 | */ |
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| 65 | protected $traits; |
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| 66 | |||
| 67 | /** |
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| 68 | * Additional list of trait adaptations |
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| 69 | * |
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| 70 | * @var TraitUseAdaptation[]|array |
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| 71 | */ |
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| 72 | protected $traitAdaptations; |
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| 73 | |||
| 74 | /** |
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| 75 | * @var array|ReflectionMethod[] |
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| 76 | */ |
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| 77 | protected $methods; |
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| 78 | |||
| 79 | /** |
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| 80 | * Namespace name |
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| 81 | * |
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| 82 | * @var string |
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| 83 | */ |
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| 84 | protected $namespaceName = ''; |
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| 85 | |||
| 86 | /** |
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| 87 | * Parent class, or false if not present, null if uninitialized yet |
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| 88 | * |
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| 89 | * @var \ReflectionClass|false|null |
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| 90 | */ |
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| 91 | protected $parentClass; |
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| 92 | |||
| 93 | /** |
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| 94 | * @var array|ReflectionProperty[] |
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| 95 | */ |
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| 96 | protected $properties; |
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| 97 | |||
| 98 | /** |
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| 99 | * @var array|ReflectionClassConstant[] |
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| 100 | */ |
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| 101 | protected $classConstants; |
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| 102 | |||
| 103 | /** |
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| 104 | * Returns the string representation of the ReflectionClass object. |
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| 105 | * |
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| 106 | * @return string |
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| 107 | */ |
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| 108 | public function __toString() |
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| 109 | { |
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| 110 | $isObject = $this instanceof \ReflectionObject; |
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| 111 | |||
| 112 | $staticProperties = $staticMethods = $defaultProperties = $dynamicProperties = $methods = []; |
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| 113 | |||
| 114 | $format = "%s [ <user> %sclass %s%s%s ] {\n"; |
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| 115 | $format .= " @@ %s %d-%d\n\n"; |
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| 116 | $format .= " - Constants [%d] {%s\n }\n\n"; |
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| 117 | $format .= " - Static properties [%d] {%s\n }\n\n"; |
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| 118 | $format .= " - Static methods [%d] {%s\n }\n\n"; |
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| 119 | $format .= " - Properties [%d] {%s\n }\n\n"; |
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| 120 | $format .= ($isObject ? " - Dynamic properties [%d] {%s\n }\n\n" : '%s%s'); |
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| 121 | $format .= " - Methods [%d] {%s\n }\n"; |
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| 122 | $format .= "}\n"; |
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| 123 | |||
| 124 | foreach ($this->getProperties() as $property) { |
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| 125 | if ($property->isStatic()) { |
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| 126 | $staticProperties[] = $property; |
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| 127 | } elseif ($property->isDefault()) { |
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| 128 | $defaultProperties[] = $property; |
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| 129 | } else { |
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| 130 | $dynamicProperties[] = $property; |
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| 131 | } |
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| 132 | } |
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| 133 | |||
| 134 | foreach ($this->getMethods() as $method) { |
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| 135 | if ($method->isStatic()) { |
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| 136 | $staticMethods[] = $method; |
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| 137 | } else { |
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| 138 | $methods[] = $method; |
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| 139 | } |
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| 140 | } |
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| 141 | |||
| 142 | $buildString = function (array $items, $indentLevel = 4) { |
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| 143 | if (!count($items)) { |
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| 144 | return ''; |
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| 145 | } |
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| 146 | $indent = "\n" . str_repeat(' ', $indentLevel); |
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| 147 | return $indent . implode($indent, explode("\n", implode("\n", $items))); |
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| 148 | }; |
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| 149 | $buildConstants = function (array $items, $indentLevel = 4) { |
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| 150 | $str = ''; |
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| 151 | foreach ($items as $name => $value) { |
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| 152 | $str .= "\n" . str_repeat(' ', $indentLevel); |
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| 153 | $str .= sprintf( |
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| 154 | 'Constant [ %s %s ] { %s }', |
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| 155 | gettype($value), |
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| 156 | $name, |
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| 157 | $value |
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| 158 | ); |
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| 159 | } |
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| 160 | return $str; |
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| 161 | }; |
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| 162 | $interfaceNames = $this->getInterfaceNames(); |
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| 163 | $parentClass = $this->getParentClass(); |
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| 164 | $modifiers = ''; |
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| 165 | if ($this->isAbstract()) { |
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| 166 | $modifiers = 'abstract '; |
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| 167 | } elseif ($this->isFinal()) { |
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| 168 | $modifiers = 'final '; |
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| 169 | }; |
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| 170 | |||
| 171 | $string = sprintf( |
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| 172 | $format, |
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| 173 | ($isObject ? 'Object of class' : 'Class'), |
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| 174 | $modifiers, |
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| 175 | $this->getName(), |
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| 176 | false !== $parentClass ? (' extends ' . $parentClass->getName()) : '', |
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| 177 | $interfaceNames ? (' implements ' . implode(', ', $interfaceNames)) : '', |
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| 178 | $this->getFileName(), |
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| 179 | $this->getStartLine(), |
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| 180 | $this->getEndLine(), |
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| 181 | count($this->getConstants()), |
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| 182 | $buildConstants($this->getConstants()), |
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| 183 | count($staticProperties), |
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| 184 | $buildString($staticProperties), |
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| 185 | count($staticMethods), |
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| 186 | $buildString($staticMethods), |
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| 187 | count($defaultProperties), |
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| 188 | $buildString($defaultProperties), |
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| 189 | $isObject ? count($dynamicProperties) : '', |
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| 190 | $isObject ? $buildString($dynamicProperties) : '', |
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| 191 | count($methods), |
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| 192 | $buildString($methods) |
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| 193 | ); |
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| 194 | |||
| 195 | return $string; |
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| 196 | } |
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| 197 | |||
| 198 | |||
| 199 | /** |
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| 200 | * {@inheritDoc} |
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| 201 | */ |
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| 202 | 10 | public function getConstant($name) |
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| 210 | |||
| 211 | /** |
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| 212 | * {@inheritDoc} |
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| 213 | */ |
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| 214 | 38 | public function getConstants() |
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| 225 | |||
| 226 | /** |
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| 227 | * {@inheritDoc} |
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| 228 | */ |
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| 229 | 19 | public function getConstructor() |
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| 238 | |||
| 239 | /** |
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| 240 | * Gets default properties from a class (including inherited properties). |
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| 241 | * |
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| 242 | * @link http://php.net/manual/en/reflectionclass.getdefaultproperties.php |
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| 243 | * |
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| 244 | * @return array An array of default properties, with the key being the name of the property and the value being |
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| 245 | * the default value of the property or NULL if the property doesn't have a default value |
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| 246 | */ |
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| 247 | 29 | public function getDefaultProperties() |
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| 248 | { |
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| 249 | 29 | $defaultValues = []; |
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| 250 | 29 | $properties = $this->getProperties(); |
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| 251 | 29 | $staticOrder = [true, false]; |
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| 252 | 29 | foreach ($staticOrder as $shouldBeStatic) { |
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| 253 | 29 | foreach ($properties as $property) { |
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| 254 | 7 | $isStaticProperty = $property->isStatic(); |
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| 255 | 7 | if ($shouldBeStatic !== $isStaticProperty) { |
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| 256 | 7 | continue; |
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| 257 | } |
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| 258 | 7 | $propertyName = $property->getName(); |
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| 259 | 7 | $isInternalReflection = get_class($property) == \ReflectionProperty::class; |
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| 260 | |||
| 261 | 7 | if (!$isInternalReflection || $isStaticProperty) { |
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| 262 | 7 | $defaultValues[$propertyName] = $property->getValue(); |
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| 263 | } elseif (!$isStaticProperty) { |
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| 264 | // Internal reflection and dynamic property |
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| 265 | $classProperties = $property->getDeclaringClass()->getDefaultProperties(); |
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| 266 | $defaultValues[$propertyName] = $classProperties[$propertyName]; |
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| 267 | } |
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| 268 | } |
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| 269 | } |
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| 270 | |||
| 271 | 29 | return $defaultValues; |
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| 272 | } |
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| 273 | |||
| 274 | /** |
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| 275 | * {@inheritDoc} |
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| 276 | */ |
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| 277 | 29 | public function getDocComment() |
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| 283 | |||
| 284 | 29 | public function getEndLine() |
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| 288 | |||
| 289 | 29 | public function getExtension() |
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| 293 | |||
| 294 | 29 | public function getExtensionName() |
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| 298 | |||
| 299 | 21 | public function getFileName() |
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| 303 | |||
| 304 | /** |
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| 305 | * {@inheritDoc} |
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| 306 | */ |
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| 307 | 30 | public function getInterfaceNames() |
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| 311 | |||
| 312 | /** |
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| 313 | * {@inheritDoc} |
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| 314 | */ |
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| 315 | 59 | public function getInterfaces() |
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| 328 | |||
| 329 | /** |
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| 330 | * {@inheritdoc} |
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| 331 | * @param string $name |
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| 332 | */ |
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| 333 | 2047 | public function getMethod($name) |
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| 344 | |||
| 345 | /** |
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| 346 | * Returns list of reflection methods |
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| 347 | * |
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| 348 | * @param null|integer $filter Optional filter |
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| 349 | * |
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| 350 | * @return array|\ReflectionMethod[] |
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| 351 | */ |
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| 352 | 2073 | public function getMethods($filter = null) |
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| 383 | |||
| 384 | /** |
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| 385 | * Returns a bitfield of the access modifiers for this class. |
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| 386 | * |
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| 387 | * @link http://php.net/manual/en/reflectionclass.getmodifiers.php |
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| 388 | * |
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| 389 | * NB: this method is not fully compatible with original value because of hidden internal constants |
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| 390 | * |
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| 391 | * @return int |
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| 392 | */ |
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| 393 | public function getModifiers() |
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| 394 | { |
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| 395 | $modifiers = 0; |
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| 396 | |||
| 397 | if ($this->isFinal()) { |
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| 398 | $modifiers += \ReflectionClass::IS_FINAL; |
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| 399 | } |
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| 400 | |||
| 401 | if (PHP_VERSION_ID < 70000 && $this->isTrait()) { |
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| 402 | $modifiers += \ReflectionClass::IS_EXPLICIT_ABSTRACT; |
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| 403 | } |
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| 404 | |||
| 405 | if ($this->classLikeNode instanceof Class_ && $this->classLikeNode->isAbstract()) { |
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| 406 | $modifiers += \ReflectionClass::IS_EXPLICIT_ABSTRACT; |
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| 407 | } |
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| 408 | |||
| 409 | if ($this->isInterface()) { |
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| 410 | $abstractMethods = $this->getMethods(); |
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| 411 | } else { |
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| 412 | $abstractMethods = $this->getMethods(\ReflectionMethod::IS_ABSTRACT); |
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| 413 | } |
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| 414 | if (!empty($abstractMethods)) { |
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| 415 | $modifiers += \ReflectionClass::IS_IMPLICIT_ABSTRACT; |
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| 416 | } |
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| 417 | |||
| 418 | return $modifiers; |
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| 419 | } |
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| 420 | |||
| 421 | /** |
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| 422 | * {@inheritDoc} |
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| 423 | */ |
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| 424 | 3001 | public function getName() |
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| 430 | |||
| 431 | /** |
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| 432 | * {@inheritDoc} |
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| 433 | */ |
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| 434 | 50 | public function getNamespaceName() |
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| 438 | |||
| 439 | /** |
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| 440 | * {@inheritDoc} |
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| 441 | */ |
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| 442 | 235 | public function getParentClass() |
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| 459 | |||
| 460 | /** |
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| 461 | * Retrieves reflected properties. |
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| 462 | * |
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| 463 | * @param int $filter The optional filter, for filtering desired property types. |
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| 464 | * It's configured using the ReflectionProperty constants, and defaults to all property types. |
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| 465 | * |
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| 466 | * @return array|\Go\ParserReflection\ReflectionProperty[] |
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| 467 | */ |
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| 468 | 318 | public function getProperties($filter = null) |
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| 501 | |||
| 502 | /** |
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| 503 | * {@inheritdoc} |
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| 504 | */ |
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| 505 | 255 | public function getProperty($name) |
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| 516 | |||
| 517 | /** |
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| 518 | * @inheritDoc |
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| 519 | */ |
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| 520 | 3 | public function getReflectionConstant($name) |
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| 521 | { |
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| 522 | 3 | $classConstants = $this->getReflectionConstants(); |
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| 523 | 3 | foreach ($classConstants as $classConstant) { |
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| 524 | 3 | if ($classConstant->getName() == $name) { |
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| 525 | 3 | return $classConstant; |
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| 526 | } |
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| 527 | } |
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| 528 | |||
| 529 | 1 | return false; |
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| 530 | } |
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| 531 | |||
| 532 | /** |
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| 533 | * @inheritDoc |
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| 534 | */ |
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| 535 | 8 | public function getReflectionConstants() |
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| 536 | { |
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| 537 | 8 | if (!isset($this->classConstants)) { |
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| 538 | 8 | $directClassConstants = ReflectionClassConstant::collectFromClassNode($this->classLikeNode, $this->getName()); |
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| 539 | 8 | $parentClassConstants = $this->recursiveCollect(function (array &$result, \ReflectionClass $instance, $isParent) { |
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| 540 | 2 | $reflectionClassConstants = []; |
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| 541 | 2 | foreach ($instance->getReflectionConstants() as $reflectionClassConstant) { |
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| 542 | 2 | if (!$isParent || !$reflectionClassConstant->isPrivate()) { |
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| 543 | 2 | $reflectionClassConstants[$reflectionClassConstant->name] = $reflectionClassConstant; |
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| 544 | } |
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| 545 | } |
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| 546 | 2 | $result += $reflectionClassConstants; |
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| 547 | 8 | }); |
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| 548 | 8 | $classConstants = $directClassConstants + $parentClassConstants; |
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| 549 | |||
| 550 | 8 | $this->classConstants = $classConstants; |
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| 551 | } |
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| 552 | |||
| 553 | 8 | return array_values($this->classConstants); |
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| 554 | } |
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| 555 | |||
| 556 | /** |
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| 557 | * {@inheritDoc} |
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| 558 | */ |
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| 559 | 3001 | public function getShortName() |
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| 563 | |||
| 564 | 29 | public function getStartLine() |
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| 568 | |||
| 569 | /** |
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| 570 | * Returns an array of trait aliases |
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| 571 | * |
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| 572 | * @link http://php.net/manual/en/reflectionclass.gettraitaliases.php |
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| 573 | * |
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| 574 | * @return array|null an array with new method names in keys and original names (in the format "TraitName::original") in |
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| 575 | * values. |
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| 576 | */ |
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| 577 | 33 | public function getTraitAliases() |
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| 597 | |||
| 598 | /** |
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| 599 | * Returns an array of names of traits used by this class |
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| 600 | * |
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| 601 | * @link http://php.net/manual/en/reflectionclass.gettraitnames.php |
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| 602 | * |
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| 603 | * @return array |
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| 604 | */ |
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| 605 | 29 | public function getTraitNames() |
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| 609 | |||
| 610 | /** |
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| 611 | * Returns an array of traits used by this class |
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| 612 | * |
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| 613 | * @link http://php.net/manual/en/reflectionclass.gettraits.php |
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| 614 | * |
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| 615 | * @return array|\ReflectionClass[] |
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| 616 | */ |
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| 617 | 230 | public function getTraits() |
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| 627 | |||
| 628 | /** |
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| 629 | * {@inheritDoc} |
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| 630 | */ |
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| 631 | 11 | public function hasConstant($name) |
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| 638 | |||
| 639 | /** |
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| 640 | * {@inheritdoc} |
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| 641 | * @param string $name |
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| 642 | */ |
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| 643 | 20 | public function hasMethod($name) |
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| 654 | |||
| 655 | /** |
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| 656 | * {@inheritdoc} |
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| 657 | */ |
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| 658 | public function hasProperty($name) |
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| 669 | |||
| 670 | /** |
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| 671 | * {@inheritDoc} |
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| 672 | * @param string $interfaceName |
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| 673 | */ |
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| 674 | 29 | public function implementsInterface($interfaceName) |
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| 680 | |||
| 681 | /** |
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| 682 | * {@inheritDoc} |
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| 683 | */ |
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| 684 | 29 | public function inNamespace() |
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| 688 | |||
| 689 | /** |
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| 690 | * {@inheritDoc} |
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| 691 | */ |
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| 692 | 75 | public function isAbstract() |
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| 704 | |||
| 705 | /** |
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| 706 | * Currently, anonymous classes aren't supported for parsed reflection |
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| 707 | */ |
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| 708 | public function isAnonymous() |
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| 712 | |||
| 713 | /** |
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| 714 | * {@inheritDoc} |
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| 715 | */ |
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| 716 | 29 | public function isCloneable() |
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| 728 | |||
| 729 | /** |
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| 730 | * {@inheritDoc} |
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| 731 | */ |
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| 732 | 29 | public function isFinal() |
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| 738 | |||
| 739 | /** |
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| 740 | * {@inheritDoc} |
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| 741 | */ |
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| 742 | public function isInstance($object) |
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| 751 | |||
| 752 | /** |
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| 753 | * {@inheritDoc} |
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| 754 | */ |
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| 755 | 29 | public function isInstantiable() |
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| 767 | |||
| 768 | /** |
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| 769 | * {@inheritDoc} |
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| 770 | */ |
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| 771 | 242 | public function isInterface() |
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| 775 | |||
| 776 | /** |
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| 777 | * {@inheritDoc} |
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| 778 | */ |
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| 779 | 29 | public function isInternal() |
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| 784 | |||
| 785 | /** |
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| 786 | * {@inheritDoc} |
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| 787 | */ |
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| 788 | 29 | public function isIterateable() |
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| 792 | |||
| 793 | /** |
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| 794 | * {@inheritDoc} |
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| 795 | */ |
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| 796 | public function isSubclassOf($class) |
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| 819 | |||
| 820 | /** |
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| 821 | * {@inheritDoc} |
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| 822 | */ |
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| 823 | 106 | public function isTrait() |
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| 827 | |||
| 828 | /** |
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| 829 | * {@inheritDoc} |
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| 830 | */ |
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| 831 | 29 | public function isUserDefined() |
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| 836 | |||
| 837 | /** |
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| 838 | * Gets static properties |
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| 839 | * |
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| 840 | * @link http://php.net/manual/en/reflectionclass.getstaticproperties.php |
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| 841 | * |
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| 842 | * @return array |
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| 843 | */ |
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| 844 | 30 | public function getStaticProperties() |
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| 865 | |||
| 866 | /** |
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| 867 | * Gets static property value |
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| 868 | * |
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| 869 | * @param string $name The name of the static property for which to return a value. |
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| 870 | * @param mixed $default A default value to return in case the class does not declare |
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| 871 | * a static property with the given name |
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| 872 | * |
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| 873 | * @return mixed |
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| 874 | * @throws ReflectionException If there is no such property and no default value was given |
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| 875 | */ |
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| 876 | 1 | public function getStaticPropertyValue($name, $default = null) |
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| 887 | |||
| 888 | |||
| 889 | /** |
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| 890 | * Creates a new class instance from given arguments. |
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| 891 | * |
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| 892 | * @link http://php.net/manual/en/reflectionclass.newinstance.php |
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| 893 | * |
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| 894 | * Signature was hacked to support both 5.6, 7.1.x and 7.2.0 versions |
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| 895 | * @see https://3v4l.org/hW9O9 |
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| 896 | * @see https://3v4l.org/sWT3j |
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| 897 | * @see https://3v4l.org/eeVf8 |
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| 898 | * |
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| 899 | * @param mixed $arg First argument |
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| 900 | * @param mixed $args Accepts a variable number of arguments which are passed to the class constructor |
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| 901 | * |
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| 902 | * @return object |
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| 903 | */ |
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| 904 | 1 | public function newInstance($arg = null, ...$args) |
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| 911 | |||
| 912 | /** |
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| 913 | * Creates a new class instance from given arguments. |
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| 914 | * |
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| 915 | * @link http://php.net/manual/en/reflectionclass.newinstanceargs.php |
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| 916 | * |
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| 917 | * @param array $args The parameters to be passed to the class constructor as an array. |
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| 918 | * |
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| 919 | * @return object |
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| 920 | */ |
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| 921 | 1 | public function newInstanceArgs(array $args = []) |
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| 928 | |||
| 929 | /** |
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| 930 | * Creates a new class instance without invoking the constructor. |
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| 931 | * |
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| 932 | * @link http://php.net/manual/en/reflectionclass.newinstancewithoutconstructor.php |
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| 933 | * |
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| 934 | * @return object |
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| 935 | */ |
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| 936 | 1 | public function newInstanceWithoutConstructor($args = null) |
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| 943 | |||
| 944 | /** |
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| 945 | * Sets static property value |
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| 946 | * |
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| 947 | * @link http://php.net/manual/en/reflectionclass.setstaticpropertyvalue.php |
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| 948 | * |
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| 949 | * @param string $name Property name |
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| 950 | * @param mixed $value New property value |
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| 951 | */ |
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| 952 | 1 | public function setStaticPropertyValue($name, $value) |
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| 958 | |||
| 959 | 172 | private function recursiveCollect(\Closure $collector) |
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| 981 | |||
| 982 | /** |
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| 983 | * Collects list of constants from the class itself |
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| 984 | */ |
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| 985 | 38 | private function collectSelfConstants() |
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| 1004 | |||
| 1005 | /** |
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| 1006 | * Create a ReflectionClass for a given class name. |
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| 1007 | * |
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| 1008 | * @param string $className |
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| 1009 | * The name of the class to create a reflection for. |
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| 1010 | * |
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| 1011 | * @return ReflectionClass |
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| 1012 | * The apropriate reflection object. |
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| 1013 | */ |
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| 1014 | abstract protected function createReflectionForClass($className); |
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| 1015 | } |
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| 1016 |
Let’s take a look at an example:
In the above example, the authenticate() method works fine as long as you just pass instances of MyUser. However, if you now also want to pass a different sub-classes of User which does not have a getDisplayName() method, the code will break.
Available Fixes
Change the type-hint for the parameter:
Add an additional type-check:
Add the method to the parent class: