Chris@0: <?php
Chris@0: 
Chris@0: namespace PhpParser;
Chris@0: 
Chris@0: /*
Chris@0:  * This parser is based on a skeleton written by Moriyoshi Koizumi, which in
Chris@0:  * turn is based on work by Masato Bito.
Chris@0:  */
Chris@0: use PhpParser\Node\Name;
Chris@0: use PhpParser\Node\Param;
Chris@0: use PhpParser\Node\Scalar\LNumber;
Chris@0: use PhpParser\Node\Scalar\String_;
Chris@0: use PhpParser\Node\Stmt\Class_;
Chris@0: use PhpParser\Node\Stmt\ClassConst;
Chris@0: use PhpParser\Node\Stmt\ClassMethod;
Chris@0: use PhpParser\Node\Stmt\Interface_;
Chris@0: use PhpParser\Node\Stmt\Namespace_;
Chris@0: use PhpParser\Node\Stmt\Property;
Chris@0: use PhpParser\Node\Stmt\TryCatch;
Chris@0: use PhpParser\Node\Stmt\UseUse;
Chris@0: 
Chris@0: abstract class ParserAbstract implements Parser
Chris@0: {
Chris@0:     const SYMBOL_NONE = -1;
Chris@0: 
Chris@0:     /*
Chris@0:      * The following members will be filled with generated parsing data:
Chris@0:      */
Chris@0: 
Chris@0:     /** @var int Size of $tokenToSymbol map */
Chris@0:     protected $tokenToSymbolMapSize;
Chris@0:     /** @var int Size of $action table */
Chris@0:     protected $actionTableSize;
Chris@0:     /** @var int Size of $goto table */
Chris@0:     protected $gotoTableSize;
Chris@0: 
Chris@0:     /** @var int Symbol number signifying an invalid token */
Chris@0:     protected $invalidSymbol;
Chris@0:     /** @var int Symbol number of error recovery token */
Chris@0:     protected $errorSymbol;
Chris@0:     /** @var int Action number signifying default action */
Chris@0:     protected $defaultAction;
Chris@0:     /** @var int Rule number signifying that an unexpected token was encountered */
Chris@0:     protected $unexpectedTokenRule;
Chris@0: 
Chris@0:     protected $YY2TBLSTATE;
Chris@0:     protected $YYNLSTATES;
Chris@0: 
Chris@0:     /** @var array Map of lexer tokens to internal symbols */
Chris@0:     protected $tokenToSymbol;
Chris@0:     /** @var array Map of symbols to their names */
Chris@0:     protected $symbolToName;
Chris@0:     /** @var array Names of the production rules (only necessary for debugging) */
Chris@0:     protected $productions;
Chris@0: 
Chris@0:     /** @var array Map of states to a displacement into the $action table. The corresponding action for this
Chris@0:      *             state/symbol pair is $action[$actionBase[$state] + $symbol]. If $actionBase[$state] is 0, the
Chris@0:                    action is defaulted, i.e. $actionDefault[$state] should be used instead. */
Chris@0:     protected $actionBase;
Chris@0:     /** @var array Table of actions. Indexed according to $actionBase comment. */
Chris@0:     protected $action;
Chris@0:     /** @var array Table indexed analogously to $action. If $actionCheck[$actionBase[$state] + $symbol] != $symbol
Chris@0:      *             then the action is defaulted, i.e. $actionDefault[$state] should be used instead. */
Chris@0:     protected $actionCheck;
Chris@0:     /** @var array Map of states to their default action */
Chris@0:     protected $actionDefault;
Chris@0: 
Chris@0:     /** @var array Map of non-terminals to a displacement into the $goto table. The corresponding goto state for this
Chris@0:      *             non-terminal/state pair is $goto[$gotoBase[$nonTerminal] + $state] (unless defaulted) */
Chris@0:     protected $gotoBase;
Chris@0:     /** @var array Table of states to goto after reduction. Indexed according to $gotoBase comment. */
Chris@0:     protected $goto;
Chris@0:     /** @var array Table indexed analogously to $goto. If $gotoCheck[$gotoBase[$nonTerminal] + $state] != $nonTerminal
Chris@0:      *             then the goto state is defaulted, i.e. $gotoDefault[$nonTerminal] should be used. */
Chris@0:     protected $gotoCheck;
Chris@0:     /** @var array Map of non-terminals to the default state to goto after their reduction */
Chris@0:     protected $gotoDefault;
Chris@0: 
Chris@0:     /** @var array Map of rules to the non-terminal on their left-hand side, i.e. the non-terminal to use for
Chris@0:      *             determining the state to goto after reduction. */
Chris@0:     protected $ruleToNonTerminal;
Chris@0:     /** @var array Map of rules to the length of their right-hand side, which is the number of elements that have to
Chris@0:      *             be popped from the stack(s) on reduction. */
Chris@0:     protected $ruleToLength;
Chris@0: 
Chris@0:     /*
Chris@0:      * The following members are part of the parser state:
Chris@0:      */
Chris@0: 
Chris@0:     /** @var Lexer Lexer that is used when parsing */
Chris@0:     protected $lexer;
Chris@0:     /** @var mixed Temporary value containing the result of last semantic action (reduction) */
Chris@0:     protected $semValue;
Chris@0:     /** @var int Position in stacks (state stack, semantic value stack, attribute stack) */
Chris@0:     protected $stackPos;
Chris@0:     /** @var array Semantic value stack (contains values of tokens and semantic action results) */
Chris@0:     protected $semStack;
Chris@0:     /** @var array[] Start attribute stack */
Chris@0:     protected $startAttributeStack;
Chris@0:     /** @var array[] End attribute stack */
Chris@0:     protected $endAttributeStack;
Chris@0:     /** @var array End attributes of last *shifted* token */
Chris@0:     protected $endAttributes;
Chris@0:     /** @var array Start attributes of last *read* token */
Chris@0:     protected $lookaheadStartAttributes;
Chris@0: 
Chris@0:     /** @var ErrorHandler Error handler */
Chris@0:     protected $errorHandler;
Chris@0:     /** @var Error[] Errors collected during last parse */
Chris@0:     protected $errors;
Chris@0:     /** @var int Error state, used to avoid error floods */
Chris@0:     protected $errorState;
Chris@0: 
Chris@0:     /**
Chris@0:      * Creates a parser instance.
Chris@0:      *
Chris@0:      * @param Lexer $lexer A lexer
Chris@0:      * @param array $options Options array. Currently no options are supported.
Chris@0:      */
Chris@0:     public function __construct(Lexer $lexer, array $options = array()) {
Chris@0:         $this->lexer = $lexer;
Chris@0:         $this->errors = array();
Chris@0: 
Chris@0:         if (isset($options['throwOnError'])) {
Chris@0:             throw new \LogicException(
Chris@0:                 '"throwOnError" is no longer supported, use "errorHandler" instead');
Chris@0:         }
Chris@0:     }
Chris@0: 
Chris@0:     /**
Chris@0:      * Parses PHP code into a node tree.
Chris@0:      *
Chris@0:      * If a non-throwing error handler is used, the parser will continue parsing after an error
Chris@0:      * occurred and attempt to build a partial AST.
Chris@0:      *
Chris@0:      * @param string $code The source code to parse
Chris@0:      * @param ErrorHandler|null $errorHandler Error handler to use for lexer/parser errors, defaults
Chris@0:      *                                        to ErrorHandler\Throwing.
Chris@0:      *
Chris@0:      * @return Node[]|null Array of statements (or null if the 'throwOnError' option is disabled and the parser was
Chris@0:      *                     unable to recover from an error).
Chris@0:      */
Chris@0:     public function parse($code, ErrorHandler $errorHandler = null) {
Chris@0:         $this->errorHandler = $errorHandler ?: new ErrorHandler\Throwing;
Chris@0: 
Chris@0:         // Initialize the lexer
Chris@0:         $this->lexer->startLexing($code, $this->errorHandler);
Chris@0: 
Chris@0:         // We start off with no lookahead-token
Chris@0:         $symbol = self::SYMBOL_NONE;
Chris@0: 
Chris@0:         // The attributes for a node are taken from the first and last token of the node.
Chris@0:         // From the first token only the startAttributes are taken and from the last only
Chris@0:         // the endAttributes. Both are merged using the array union operator (+).
Chris@0:         $startAttributes = '*POISON';
Chris@0:         $endAttributes = '*POISON';
Chris@0:         $this->endAttributes = $endAttributes;
Chris@0: 
Chris@0:         // Keep stack of start and end attributes
Chris@0:         $this->startAttributeStack = array();
Chris@0:         $this->endAttributeStack = array($endAttributes);
Chris@0: 
Chris@0:         // Start off in the initial state and keep a stack of previous states
Chris@0:         $state = 0;
Chris@0:         $stateStack = array($state);
Chris@0: 
Chris@0:         // Semantic value stack (contains values of tokens and semantic action results)
Chris@0:         $this->semStack = array();
Chris@0: 
Chris@0:         // Current position in the stack(s)
Chris@0:         $this->stackPos = 0;
Chris@0: 
Chris@0:         $this->errorState = 0;
Chris@0: 
Chris@0:         for (;;) {
Chris@0:             //$this->traceNewState($state, $symbol);
Chris@0: 
Chris@0:             if ($this->actionBase[$state] == 0) {
Chris@0:                 $rule = $this->actionDefault[$state];
Chris@0:             } else {
Chris@0:                 if ($symbol === self::SYMBOL_NONE) {
Chris@0:                     // Fetch the next token id from the lexer and fetch additional info by-ref.
Chris@0:                     // The end attributes are fetched into a temporary variable and only set once the token is really
Chris@0:                     // shifted (not during read). Otherwise you would sometimes get off-by-one errors, when a rule is
Chris@0:                     // reduced after a token was read but not yet shifted.
Chris@0:                     $tokenId = $this->lexer->getNextToken($tokenValue, $startAttributes, $endAttributes);
Chris@0: 
Chris@0:                     // map the lexer token id to the internally used symbols
Chris@0:                     $symbol = $tokenId >= 0 && $tokenId < $this->tokenToSymbolMapSize
Chris@0:                         ? $this->tokenToSymbol[$tokenId]
Chris@0:                         : $this->invalidSymbol;
Chris@0: 
Chris@0:                     if ($symbol === $this->invalidSymbol) {
Chris@0:                         throw new \RangeException(sprintf(
Chris@0:                             'The lexer returned an invalid token (id=%d, value=%s)',
Chris@0:                             $tokenId, $tokenValue
Chris@0:                         ));
Chris@0:                     }
Chris@0: 
Chris@0:                     // This is necessary to assign some meaningful attributes to /* empty */ productions. They'll get
Chris@0:                     // the attributes of the next token, even though they don't contain it themselves.
Chris@0:                     $this->startAttributeStack[$this->stackPos+1] = $startAttributes;
Chris@0:                     $this->endAttributeStack[$this->stackPos+1] = $endAttributes;
Chris@0:                     $this->lookaheadStartAttributes = $startAttributes;
Chris@0: 
Chris@0:                     //$this->traceRead($symbol);
Chris@0:                 }
Chris@0: 
Chris@0:                 $idx = $this->actionBase[$state] + $symbol;
Chris@0:                 if ((($idx >= 0 && $idx < $this->actionTableSize && $this->actionCheck[$idx] == $symbol)
Chris@0:                      || ($state < $this->YY2TBLSTATE
Chris@0:                          && ($idx = $this->actionBase[$state + $this->YYNLSTATES] + $symbol) >= 0
Chris@0:                          && $idx < $this->actionTableSize && $this->actionCheck[$idx] == $symbol))
Chris@0:                     && ($action = $this->action[$idx]) != $this->defaultAction) {
Chris@0:                     /*
Chris@0:                      * >= YYNLSTATES: shift and reduce
Chris@0:                      * > 0: shift
Chris@0:                      * = 0: accept
Chris@0:                      * < 0: reduce
Chris@0:                      * = -YYUNEXPECTED: error
Chris@0:                      */
Chris@0:                     if ($action > 0) {
Chris@0:                         /* shift */
Chris@0:                         //$this->traceShift($symbol);
Chris@0: 
Chris@0:                         ++$this->stackPos;
Chris@0:                         $stateStack[$this->stackPos] = $state = $action;
Chris@0:                         $this->semStack[$this->stackPos] = $tokenValue;
Chris@0:                         $this->startAttributeStack[$this->stackPos] = $startAttributes;
Chris@0:                         $this->endAttributeStack[$this->stackPos] = $endAttributes;
Chris@0:                         $this->endAttributes = $endAttributes;
Chris@0:                         $symbol = self::SYMBOL_NONE;
Chris@0: 
Chris@0:                         if ($this->errorState) {
Chris@0:                             --$this->errorState;
Chris@0:                         }
Chris@0: 
Chris@0:                         if ($action < $this->YYNLSTATES) {
Chris@0:                             continue;
Chris@0:                         }
Chris@0: 
Chris@0:                         /* $yyn >= YYNLSTATES means shift-and-reduce */
Chris@0:                         $rule = $action - $this->YYNLSTATES;
Chris@0:                     } else {
Chris@0:                         $rule = -$action;
Chris@0:                     }
Chris@0:                 } else {
Chris@0:                     $rule = $this->actionDefault[$state];
Chris@0:                 }
Chris@0:             }
Chris@0: 
Chris@0:             for (;;) {
Chris@0:                 if ($rule === 0) {
Chris@0:                     /* accept */
Chris@0:                     //$this->traceAccept();
Chris@0:                     return $this->semValue;
Chris@0:                 } elseif ($rule !== $this->unexpectedTokenRule) {
Chris@0:                     /* reduce */
Chris@0:                     //$this->traceReduce($rule);
Chris@0: 
Chris@0:                     try {
Chris@0:                         $this->{'reduceRule' . $rule}();
Chris@0:                     } catch (Error $e) {
Chris@0:                         if (-1 === $e->getStartLine() && isset($startAttributes['startLine'])) {
Chris@0:                             $e->setStartLine($startAttributes['startLine']);
Chris@0:                         }
Chris@0: 
Chris@0:                         $this->emitError($e);
Chris@0:                         // Can't recover from this type of error
Chris@0:                         return null;
Chris@0:                     }
Chris@0: 
Chris@0:                     /* Goto - shift nonterminal */
Chris@0:                     $lastEndAttributes = $this->endAttributeStack[$this->stackPos];
Chris@0:                     $this->stackPos -= $this->ruleToLength[$rule];
Chris@0:                     $nonTerminal = $this->ruleToNonTerminal[$rule];
Chris@0:                     $idx = $this->gotoBase[$nonTerminal] + $stateStack[$this->stackPos];
Chris@0:                     if ($idx >= 0 && $idx < $this->gotoTableSize && $this->gotoCheck[$idx] == $nonTerminal) {
Chris@0:                         $state = $this->goto[$idx];
Chris@0:                     } else {
Chris@0:                         $state = $this->gotoDefault[$nonTerminal];
Chris@0:                     }
Chris@0: 
Chris@0:                     ++$this->stackPos;
Chris@0:                     $stateStack[$this->stackPos]     = $state;
Chris@0:                     $this->semStack[$this->stackPos] = $this->semValue;
Chris@0:                     $this->endAttributeStack[$this->stackPos] = $lastEndAttributes;
Chris@0:                 } else {
Chris@0:                     /* error */
Chris@0:                     switch ($this->errorState) {
Chris@0:                         case 0:
Chris@0:                             $msg = $this->getErrorMessage($symbol, $state);
Chris@0:                             $this->emitError(new Error($msg, $startAttributes + $endAttributes));
Chris@0:                             // Break missing intentionally
Chris@0:                         case 1:
Chris@0:                         case 2:
Chris@0:                             $this->errorState = 3;
Chris@0: 
Chris@0:                             // Pop until error-expecting state uncovered
Chris@0:                             while (!(
Chris@0:                                 (($idx = $this->actionBase[$state] + $this->errorSymbol) >= 0
Chris@0:                                     && $idx < $this->actionTableSize && $this->actionCheck[$idx] == $this->errorSymbol)
Chris@0:                                 || ($state < $this->YY2TBLSTATE
Chris@0:                                     && ($idx = $this->actionBase[$state + $this->YYNLSTATES] + $this->errorSymbol) >= 0
Chris@0:                                     && $idx < $this->actionTableSize && $this->actionCheck[$idx] == $this->errorSymbol)
Chris@0:                             ) || ($action = $this->action[$idx]) == $this->defaultAction) { // Not totally sure about this
Chris@0:                                 if ($this->stackPos <= 0) {
Chris@0:                                     // Could not recover from error
Chris@0:                                     return null;
Chris@0:                                 }
Chris@0:                                 $state = $stateStack[--$this->stackPos];
Chris@0:                                 //$this->tracePop($state);
Chris@0:                             }
Chris@0: 
Chris@0:                             //$this->traceShift($this->errorSymbol);
Chris@0:                             ++$this->stackPos;
Chris@0:                             $stateStack[$this->stackPos] = $state = $action;
Chris@0: 
Chris@0:                             // We treat the error symbol as being empty, so we reset the end attributes
Chris@0:                             // to the end attributes of the last non-error symbol
Chris@0:                             $this->endAttributeStack[$this->stackPos] = $this->endAttributeStack[$this->stackPos - 1];
Chris@0:                             $this->endAttributes = $this->endAttributeStack[$this->stackPos - 1];
Chris@0:                             break;
Chris@0: 
Chris@0:                         case 3:
Chris@0:                             if ($symbol === 0) {
Chris@0:                                 // Reached EOF without recovering from error
Chris@0:                                 return null;
Chris@0:                             }
Chris@0: 
Chris@0:                             //$this->traceDiscard($symbol);
Chris@0:                             $symbol = self::SYMBOL_NONE;
Chris@0:                             break 2;
Chris@0:                     }
Chris@0:                 }
Chris@0: 
Chris@0:                 if ($state < $this->YYNLSTATES) {
Chris@0:                     break;
Chris@0:                 }
Chris@0: 
Chris@0:                 /* >= YYNLSTATES means shift-and-reduce */
Chris@0:                 $rule = $state - $this->YYNLSTATES;
Chris@0:             }
Chris@0:         }
Chris@0: 
Chris@0:         throw new \RuntimeException('Reached end of parser loop');
Chris@0:     }
Chris@0: 
Chris@0:     protected function emitError(Error $error) {
Chris@0:         $this->errorHandler->handleError($error);
Chris@0:     }
Chris@0: 
Chris@0:     protected function getErrorMessage($symbol, $state) {
Chris@0:         $expectedString = '';
Chris@0:         if ($expected = $this->getExpectedTokens($state)) {
Chris@0:             $expectedString = ', expecting ' . implode(' or ', $expected);
Chris@0:         }
Chris@0: 
Chris@0:         return 'Syntax error, unexpected ' . $this->symbolToName[$symbol] . $expectedString;
Chris@0:     }
Chris@0: 
Chris@0:     protected function getExpectedTokens($state) {
Chris@0:         $expected = array();
Chris@0: 
Chris@0:         $base = $this->actionBase[$state];
Chris@0:         foreach ($this->symbolToName as $symbol => $name) {
Chris@0:             $idx = $base + $symbol;
Chris@0:             if ($idx >= 0 && $idx < $this->actionTableSize && $this->actionCheck[$idx] === $symbol
Chris@0:                 || $state < $this->YY2TBLSTATE
Chris@0:                 && ($idx = $this->actionBase[$state + $this->YYNLSTATES] + $symbol) >= 0
Chris@0:                 && $idx < $this->actionTableSize && $this->actionCheck[$idx] === $symbol
Chris@0:             ) {
Chris@0:                 if ($this->action[$idx] != $this->unexpectedTokenRule
Chris@0:                     && $this->action[$idx] != $this->defaultAction
Chris@0:                     && $symbol != $this->errorSymbol
Chris@0:                 ) {
Chris@0:                     if (count($expected) == 4) {
Chris@0:                         /* Too many expected tokens */
Chris@0:                         return array();
Chris@0:                     }
Chris@0: 
Chris@0:                     $expected[] = $name;
Chris@0:                 }
Chris@0:             }
Chris@0:         }
Chris@0: 
Chris@0:         return $expected;
Chris@0:     }
Chris@0: 
Chris@0:     /*
Chris@0:      * Tracing functions used for debugging the parser.
Chris@0:      */
Chris@0: 
Chris@0:     /*
Chris@0:     protected function traceNewState($state, $symbol) {
Chris@0:         echo '% State ' . $state
Chris@0:             . ', Lookahead ' . ($symbol == self::SYMBOL_NONE ? '--none--' : $this->symbolToName[$symbol]) . "\n";
Chris@0:     }
Chris@0: 
Chris@0:     protected function traceRead($symbol) {
Chris@0:         echo '% Reading ' . $this->symbolToName[$symbol] . "\n";
Chris@0:     }
Chris@0: 
Chris@0:     protected function traceShift($symbol) {
Chris@0:         echo '% Shift ' . $this->symbolToName[$symbol] . "\n";
Chris@0:     }
Chris@0: 
Chris@0:     protected function traceAccept() {
Chris@0:         echo "% Accepted.\n";
Chris@0:     }
Chris@0: 
Chris@0:     protected function traceReduce($n) {
Chris@0:         echo '% Reduce by (' . $n . ') ' . $this->productions[$n] . "\n";
Chris@0:     }
Chris@0: 
Chris@0:     protected function tracePop($state) {
Chris@0:         echo '% Recovering, uncovered state ' . $state . "\n";
Chris@0:     }
Chris@0: 
Chris@0:     protected function traceDiscard($symbol) {
Chris@0:         echo '% Discard ' . $this->symbolToName[$symbol] . "\n";
Chris@0:     }
Chris@0:     */
Chris@0: 
Chris@0:     /*
Chris@0:      * Helper functions invoked by semantic actions
Chris@0:      */
Chris@0: 
Chris@0:     /**
Chris@0:      * Moves statements of semicolon-style namespaces into $ns->stmts and checks various error conditions.
Chris@0:      *
Chris@0:      * @param Node[] $stmts
Chris@0:      * @return Node[]
Chris@0:      */
Chris@0:     protected function handleNamespaces(array $stmts) {
Chris@0:         $hasErrored = false;
Chris@0:         $style = $this->getNamespacingStyle($stmts);
Chris@0:         if (null === $style) {
Chris@0:             // not namespaced, nothing to do
Chris@0:             return $stmts;
Chris@0:         } elseif ('brace' === $style) {
Chris@0:             // For braced namespaces we only have to check that there are no invalid statements between the namespaces
Chris@0:             $afterFirstNamespace = false;
Chris@0:             foreach ($stmts as $stmt) {
Chris@0:                 if ($stmt instanceof Node\Stmt\Namespace_) {
Chris@0:                     $afterFirstNamespace = true;
Chris@0:                 } elseif (!$stmt instanceof Node\Stmt\HaltCompiler
Chris@0:                         && !$stmt instanceof Node\Stmt\Nop
Chris@0:                         && $afterFirstNamespace && !$hasErrored) {
Chris@0:                     $this->emitError(new Error(
Chris@0:                         'No code may exist outside of namespace {}', $stmt->getAttributes()));
Chris@0:                     $hasErrored = true; // Avoid one error for every statement
Chris@0:                 }
Chris@0:             }
Chris@0:             return $stmts;
Chris@0:         } else {
Chris@0:             // For semicolon namespaces we have to move the statements after a namespace declaration into ->stmts
Chris@0:             $resultStmts = array();
Chris@0:             $targetStmts =& $resultStmts;
Chris@0:             foreach ($stmts as $stmt) {
Chris@0:                 if ($stmt instanceof Node\Stmt\Namespace_) {
Chris@0:                     if ($stmt->stmts === null) {
Chris@0:                         $stmt->stmts = array();
Chris@0:                         $targetStmts =& $stmt->stmts;
Chris@0:                         $resultStmts[] = $stmt;
Chris@0:                     } else {
Chris@0:                         // This handles the invalid case of mixed style namespaces
Chris@0:                         $resultStmts[] = $stmt;
Chris@0:                         $targetStmts =& $resultStmts;
Chris@0:                     }
Chris@0:                 } elseif ($stmt instanceof Node\Stmt\HaltCompiler) {
Chris@0:                     // __halt_compiler() is not moved into the namespace
Chris@0:                     $resultStmts[] = $stmt;
Chris@0:                 } else {
Chris@0:                     $targetStmts[] = $stmt;
Chris@0:                 }
Chris@0:             }
Chris@0:             return $resultStmts;
Chris@0:         }
Chris@0:     }
Chris@0: 
Chris@0:     private function getNamespacingStyle(array $stmts) {
Chris@0:         $style = null;
Chris@0:         $hasNotAllowedStmts = false;
Chris@0:         foreach ($stmts as $i => $stmt) {
Chris@0:             if ($stmt instanceof Node\Stmt\Namespace_) {
Chris@0:                 $currentStyle = null === $stmt->stmts ? 'semicolon' : 'brace';
Chris@0:                 if (null === $style) {
Chris@0:                     $style = $currentStyle;
Chris@0:                     if ($hasNotAllowedStmts) {
Chris@0:                         $this->emitError(new Error(
Chris@0:                             'Namespace declaration statement has to be the very first statement in the script',
Chris@0:                             $stmt->getLine() // Avoid marking the entire namespace as an error
Chris@0:                         ));
Chris@0:                     }
Chris@0:                 } elseif ($style !== $currentStyle) {
Chris@0:                     $this->emitError(new Error(
Chris@0:                         'Cannot mix bracketed namespace declarations with unbracketed namespace declarations',
Chris@0:                         $stmt->getLine() // Avoid marking the entire namespace as an error
Chris@0:                     ));
Chris@0:                     // Treat like semicolon style for namespace normalization
Chris@0:                     return 'semicolon';
Chris@0:                 }
Chris@0:                 continue;
Chris@0:             }
Chris@0: 
Chris@0:             /* declare(), __halt_compiler() and nops can be used before a namespace declaration */
Chris@0:             if ($stmt instanceof Node\Stmt\Declare_
Chris@0:                 || $stmt instanceof Node\Stmt\HaltCompiler
Chris@0:                 || $stmt instanceof Node\Stmt\Nop) {
Chris@0:                 continue;
Chris@0:             }
Chris@0: 
Chris@0:             /* There may be a hashbang line at the very start of the file */
Chris@0:             if ($i == 0 && $stmt instanceof Node\Stmt\InlineHTML && preg_match('/\A#!.*\r?\n\z/', $stmt->value)) {
Chris@0:                 continue;
Chris@0:             }
Chris@0: 
Chris@0:             /* Everything else if forbidden before namespace declarations */
Chris@0:             $hasNotAllowedStmts = true;
Chris@0:         }
Chris@0:         return $style;
Chris@0:     }
Chris@0: 
Chris@0:     protected function handleBuiltinTypes(Name $name) {
Chris@0:         $scalarTypes = [
Chris@0:             'bool'     => true,
Chris@0:             'int'      => true,
Chris@0:             'float'    => true,
Chris@0:             'string'   => true,
Chris@0:             'iterable' => true,
Chris@0:             'void'     => true,
Chris@0:             'object'   => true,
Chris@0:         ];
Chris@0: 
Chris@0:         if (!$name->isUnqualified()) {
Chris@0:             return $name;
Chris@0:         }
Chris@0: 
Chris@0:         $lowerName = strtolower($name->toString());
Chris@0:         return isset($scalarTypes[$lowerName]) ? $lowerName : $name;
Chris@0:     }
Chris@0: 
Chris@0:     protected static $specialNames = array(
Chris@0:         'self'   => true,
Chris@0:         'parent' => true,
Chris@0:         'static' => true,
Chris@0:     );
Chris@0: 
Chris@0:     protected function getAttributesAt($pos) {
Chris@0:         return $this->startAttributeStack[$pos] + $this->endAttributeStack[$pos];
Chris@0:     }
Chris@0: 
Chris@0:     protected function parseLNumber($str, $attributes, $allowInvalidOctal = false) {
Chris@0:         try {
Chris@0:             return LNumber::fromString($str, $attributes, $allowInvalidOctal);
Chris@0:         } catch (Error $error) {
Chris@0:             $this->emitError($error);
Chris@0:             // Use dummy value
Chris@0:             return new LNumber(0, $attributes);
Chris@0:         }
Chris@0:     }
Chris@0: 
Chris@0:     protected function parseNumString($str, $attributes) {
Chris@0:         if (!preg_match('/^(?:0|-?[1-9][0-9]*)$/', $str)) {
Chris@0:             return new String_($str, $attributes);
Chris@0:         }
Chris@0: 
Chris@0:         $num = +$str;
Chris@0:         if (!is_int($num)) {
Chris@0:             return new String_($str, $attributes);
Chris@0:         }
Chris@0: 
Chris@0:         return new LNumber($num, $attributes);
Chris@0:     }
Chris@0: 
Chris@0:     protected function checkModifier($a, $b, $modifierPos) {
Chris@0:         // Jumping through some hoops here because verifyModifier() is also used elsewhere
Chris@0:         try {
Chris@0:             Class_::verifyModifier($a, $b);
Chris@0:         } catch (Error $error) {
Chris@0:             $error->setAttributes($this->getAttributesAt($modifierPos));
Chris@0:             $this->emitError($error);
Chris@0:         }
Chris@0:     }
Chris@0: 
Chris@0:     protected function checkParam(Param $node) {
Chris@0:         if ($node->variadic && null !== $node->default) {
Chris@0:             $this->emitError(new Error(
Chris@0:                 'Variadic parameter cannot have a default value',
Chris@0:                 $node->default->getAttributes()
Chris@0:             ));
Chris@0:         }
Chris@0:     }
Chris@0: 
Chris@0:     protected function checkTryCatch(TryCatch $node) {
Chris@0:         if (empty($node->catches) && null === $node->finally) {
Chris@0:             $this->emitError(new Error(
Chris@0:                 'Cannot use try without catch or finally', $node->getAttributes()
Chris@0:             ));
Chris@0:         }
Chris@0:     }
Chris@0: 
Chris@0:     protected function checkNamespace(Namespace_ $node) {
Chris@0:         if (isset(self::$specialNames[strtolower($node->name)])) {
Chris@0:             $this->emitError(new Error(
Chris@0:                 sprintf('Cannot use \'%s\' as namespace name', $node->name),
Chris@0:                 $node->name->getAttributes()
Chris@0:             ));
Chris@0:         }
Chris@0: 
Chris@0:         if (null !== $node->stmts) {
Chris@0:             foreach ($node->stmts as $stmt) {
Chris@0:                 if ($stmt instanceof Namespace_) {
Chris@0:                     $this->emitError(new Error(
Chris@0:                         'Namespace declarations cannot be nested', $stmt->getAttributes()
Chris@0:                     ));
Chris@0:                 }
Chris@0:             }
Chris@0:         }
Chris@0:     }
Chris@0: 
Chris@0:     protected function checkClass(Class_ $node, $namePos) {
Chris@0:         if (null !== $node->name && isset(self::$specialNames[strtolower($node->name)])) {
Chris@0:             $this->emitError(new Error(
Chris@0:                 sprintf('Cannot use \'%s\' as class name as it is reserved', $node->name),
Chris@0:                 $this->getAttributesAt($namePos)
Chris@0:             ));
Chris@0:         }
Chris@0: 
Chris@0:         if (isset(self::$specialNames[strtolower($node->extends)])) {
Chris@0:             $this->emitError(new Error(
Chris@0:                 sprintf('Cannot use \'%s\' as class name as it is reserved', $node->extends),
Chris@0:                 $node->extends->getAttributes()
Chris@0:             ));
Chris@0:         }
Chris@0: 
Chris@0:         foreach ($node->implements as $interface) {
Chris@0:             if (isset(self::$specialNames[strtolower($interface)])) {
Chris@0:                 $this->emitError(new Error(
Chris@0:                     sprintf('Cannot use \'%s\' as interface name as it is reserved', $interface),
Chris@0:                     $interface->getAttributes()
Chris@0:                 ));
Chris@0:             }
Chris@0:         }
Chris@0:     }
Chris@0: 
Chris@0:     protected function checkInterface(Interface_ $node, $namePos) {
Chris@0:         if (null !== $node->name && isset(self::$specialNames[strtolower($node->name)])) {
Chris@0:             $this->emitError(new Error(
Chris@0:                 sprintf('Cannot use \'%s\' as class name as it is reserved', $node->name),
Chris@0:                 $this->getAttributesAt($namePos)
Chris@0:             ));
Chris@0:         }
Chris@0: 
Chris@0:         foreach ($node->extends as $interface) {
Chris@0:             if (isset(self::$specialNames[strtolower($interface)])) {
Chris@0:                 $this->emitError(new Error(
Chris@0:                     sprintf('Cannot use \'%s\' as interface name as it is reserved', $interface),
Chris@0:                     $interface->getAttributes()
Chris@0:                 ));
Chris@0:             }
Chris@0:         }
Chris@0:     }
Chris@0: 
Chris@0:     protected function checkClassMethod(ClassMethod $node, $modifierPos) {
Chris@0:         if ($node->flags & Class_::MODIFIER_STATIC) {
Chris@0:             switch (strtolower($node->name)) {
Chris@0:                 case '__construct':
Chris@0:                     $this->emitError(new Error(
Chris@0:                         sprintf('Constructor %s() cannot be static', $node->name),
Chris@0:                         $this->getAttributesAt($modifierPos)));
Chris@0:                     break;
Chris@0:                 case '__destruct':
Chris@0:                     $this->emitError(new Error(
Chris@0:                         sprintf('Destructor %s() cannot be static', $node->name),
Chris@0:                         $this->getAttributesAt($modifierPos)));
Chris@0:                     break;
Chris@0:                 case '__clone':
Chris@0:                     $this->emitError(new Error(
Chris@0:                         sprintf('Clone method %s() cannot be static', $node->name),
Chris@0:                         $this->getAttributesAt($modifierPos)));
Chris@0:                     break;
Chris@0:             }
Chris@0:         }
Chris@0:     }
Chris@0: 
Chris@0:     protected function checkClassConst(ClassConst $node, $modifierPos) {
Chris@0:         if ($node->flags & Class_::MODIFIER_STATIC) {
Chris@0:             $this->emitError(new Error(
Chris@0:                 "Cannot use 'static' as constant modifier",
Chris@0:                 $this->getAttributesAt($modifierPos)));
Chris@0:         }
Chris@0:         if ($node->flags & Class_::MODIFIER_ABSTRACT) {
Chris@0:             $this->emitError(new Error(
Chris@0:                 "Cannot use 'abstract' as constant modifier",
Chris@0:                 $this->getAttributesAt($modifierPos)));
Chris@0:         }
Chris@0:         if ($node->flags & Class_::MODIFIER_FINAL) {
Chris@0:             $this->emitError(new Error(
Chris@0:                 "Cannot use 'final' as constant modifier",
Chris@0:                 $this->getAttributesAt($modifierPos)));
Chris@0:         }
Chris@0:     }
Chris@0: 
Chris@0:     protected function checkProperty(Property $node, $modifierPos) {
Chris@0:         if ($node->flags & Class_::MODIFIER_ABSTRACT) {
Chris@0:             $this->emitError(new Error('Properties cannot be declared abstract',
Chris@0:                 $this->getAttributesAt($modifierPos)));
Chris@0:         }
Chris@0: 
Chris@0:         if ($node->flags & Class_::MODIFIER_FINAL) {
Chris@0:             $this->emitError(new Error('Properties cannot be declared final',
Chris@0:                 $this->getAttributesAt($modifierPos)));
Chris@0:         }
Chris@0:     }
Chris@0: 
Chris@0:     protected function checkUseUse(UseUse $node, $namePos) {
Chris@0:         if ('self' == strtolower($node->alias) || 'parent' == strtolower($node->alias)) {
Chris@0:             $this->emitError(new Error(
Chris@0:                 sprintf(
Chris@0:                     'Cannot use %s as %s because \'%2$s\' is a special class name',
Chris@0:                     $node->name, $node->alias
Chris@0:                 ),
Chris@0:                 $this->getAttributesAt($namePos)
Chris@0:             ));
Chris@0:         }
Chris@0:     }
Chris@0: }