Complex classes like BaseParser 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 BaseParser, and based on these observations, apply Extract Interface, too.
| 1 | <?php |
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| 22 | abstract class BaseParser |
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| 23 | { |
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| 24 | private const SYMBOL_NONE = -1; |
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| 25 | |||
| 26 | /* |
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| 27 | * The following members will be filled with generated parsing data: |
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| 28 | */ |
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| 29 | |||
| 30 | /** @var int Size of $tokenToSymbol map */ |
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| 31 | protected $tokenToSymbolMapSize; |
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| 32 | /** @var int Size of $action table */ |
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| 33 | protected $actionTableSize; |
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| 34 | /** @var int Size of $goto table */ |
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| 35 | protected $gotoTableSize; |
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| 36 | |||
| 37 | /** @var int Symbol number signifying an invalid token */ |
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| 38 | protected $invalidSymbol; |
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| 39 | /** @var int Symbol number of error recovery token */ |
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| 40 | protected $errorSymbol; |
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| 41 | /** @var int Action number signifying default action */ |
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| 42 | protected $defaultAction; |
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| 43 | /** @var int Rule number signifying that an unexpected token was encountered */ |
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| 44 | protected $unexpectedTokenRule; |
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| 45 | /** @var int states */ |
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| 46 | protected $YY2TBLSTATE; |
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| 47 | /** @var int Number of non-leaf states */ |
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| 48 | protected $numNonLeafStates; |
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| 49 | |||
| 50 | /** @var int[] Map of lexer tokens to internal symbols */ |
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| 51 | protected $tokenToSymbol; |
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| 52 | /** @var string[] Map of symbols to their names */ |
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| 53 | protected $symbolToName; |
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| 54 | /** @var string[] Names of the production rules (only necessary for debugging) */ |
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| 55 | protected $productions; |
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| 56 | |||
| 57 | /** |
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| 58 | * @var int[] Map of states to a displacement into the $action table. The corresponding action for this |
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| 59 | * state/symbol pair is $action[$actionBase[$state] + $symbol]. If $actionBase[$state] is 0, the |
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| 60 | * action is defaulted, i.e. $actionDefault[$state] should be used instead. |
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| 61 | */ |
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| 62 | protected $actionBase; |
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| 63 | /** @var int[] Table of actions. Indexed according to $actionBase comment. */ |
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| 64 | protected $action; |
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| 65 | /** |
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| 66 | * @var int[] Table indexed analogously to $action. If $actionCheck[$actionBase[$state] + $symbol] != $symbol |
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| 67 | * then the action is defaulted, i.e. $actionDefault[$state] should be used instead. |
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| 68 | */ |
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| 69 | protected $actionCheck; |
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| 70 | /** @var int[] Map of states to their default action */ |
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| 71 | protected $actionDefault; |
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| 72 | /** @var callable[] Semantic action callbacks */ |
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| 73 | protected $reduceCallbacks; |
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| 74 | |||
| 75 | |||
| 76 | /** @var TypeLexer */ |
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| 77 | private $lexer; |
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| 78 | |||
| 79 | /** @var FqsenResolver */ |
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| 80 | protected $fqsenResolver; |
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| 81 | |||
| 82 | /** @var Context */ |
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| 83 | protected $context; |
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| 84 | |||
| 85 | /** @var Type|Type[]|null Temporary value containing the result of last semantic action (reduction) */ |
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| 86 | protected $semValue; |
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| 87 | |||
| 88 | /** @var Type[] Semantic value stack (contains values of tokens and semantic action results) */ |
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| 89 | protected $semStack; |
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| 90 | |||
| 91 | /** |
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| 92 | * @return void |
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| 93 | */ |
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| 94 | //phpcs:ignore SlevomatCodingStandard.TypeHints.ReturnTypeHint.MissingNativeTypeHint |
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| 95 | abstract protected function initReduceCallbacks(); |
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| 96 | |||
| 97 | public function __construct() |
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| 102 | |||
| 103 | public function parse(string $type) |
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| 217 | |||
| 218 | /** |
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| 219 | * Format error message including expected tokens. |
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| 220 | * |
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| 221 | * @param int $symbol Unexpected symbol |
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| 222 | * @param int $state State at time of error |
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| 223 | * |
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| 224 | * @return string Formatted error message |
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| 225 | */ |
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| 226 | protected function getErrorMessage(int $symbol, int $state) : string |
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| 235 | |||
| 236 | /** |
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| 237 | * Get limited number of expected tokens in given state. |
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| 238 | * |
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| 239 | * @param int $state State |
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| 240 | * |
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| 241 | * @return string[] Expected tokens. If too many, an empty array is returned. |
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| 242 | */ |
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| 243 | protected function getExpectedTokens(int $state) : array |
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| 282 | |||
| 283 | protected function traceNewState($state, $symbol) : void |
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| 288 | |||
| 289 | protected function traceRead($symbol, $value) : void |
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| 293 | |||
| 294 | protected function traceShift($symbol) : void |
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| 298 | |||
| 299 | protected function traceAccept() : void |
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| 303 | |||
| 304 | protected function traceReduce($n) : void |
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| 308 | |||
| 309 | protected function tracePop($state) : void |
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| 313 | |||
| 314 | protected function traceDiscard($symbol) : void |
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| 318 | } |
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| 319 |
Our type inference engine has found an assignment to a property that is incompatible with the declared type of that property.
Either this assignment is in error or the assigned type should be added to the documentation/type hint for that property..