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			287 lines
		
	
	
		
			11 KiB
		
	
	
	
		
			PHP
		
	
	
	
	
	
		
		
			
		
	
	
			287 lines
		
	
	
		
			11 KiB
		
	
	
	
		
			PHP
		
	
	
	
	
	
|   | <?php | ||
|  | 
 | ||
|  | namespace PhpParser; | ||
|  | 
 | ||
|  | class Lexer | ||
|  | { | ||
|  |     protected $code; | ||
|  |     protected $tokens; | ||
|  |     protected $pos; | ||
|  |     protected $line; | ||
|  |     protected $filePos; | ||
|  | 
 | ||
|  |     protected $tokenMap; | ||
|  |     protected $dropTokens; | ||
|  | 
 | ||
|  |     protected $usedAttributes; | ||
|  | 
 | ||
|  |     /** | ||
|  |      * Creates a Lexer. | ||
|  |      * | ||
|  |      * @param array $options Options array. Currently only the 'usedAttributes' option is supported, | ||
|  |      *                       which is an array of attributes to add to the AST nodes. Possible attributes | ||
|  |      *                       are: 'comments', 'startLine', 'endLine', 'startTokenPos', 'endTokenPos', | ||
|  |      *                       'startFilePos', 'endFilePos'. The option defaults to the first three. | ||
|  |      *                       For more info see getNextToken() docs. | ||
|  |      */ | ||
|  |     public function __construct(array $options = array()) { | ||
|  |         // map from internal tokens to PhpParser tokens
 | ||
|  |         $this->tokenMap = $this->createTokenMap(); | ||
|  | 
 | ||
|  |         // map of tokens to drop while lexing (the map is only used for isset lookup,
 | ||
|  |         // that's why the value is simply set to 1; the value is never actually used.)
 | ||
|  |         $this->dropTokens = array_fill_keys(array(T_WHITESPACE, T_OPEN_TAG), 1); | ||
|  | 
 | ||
|  |         // the usedAttributes member is a map of the used attribute names to a dummy
 | ||
|  |         // value (here "true")
 | ||
|  |         $options += array( | ||
|  |             'usedAttributes' => array('comments', 'startLine', 'endLine'), | ||
|  |         ); | ||
|  |         $this->usedAttributes = array_fill_keys($options['usedAttributes'], true); | ||
|  |     } | ||
|  | 
 | ||
|  |     /** | ||
|  |      * Initializes the lexer for lexing the provided source code. | ||
|  |      * | ||
|  |      * @param string $code The source code to lex | ||
|  |      * | ||
|  |      * @throws Error on lexing errors (unterminated comment or unexpected character) | ||
|  |      */ | ||
|  |     public function startLexing($code) { | ||
|  |         $scream = ini_set('xdebug.scream', '0'); | ||
|  | 
 | ||
|  |         $this->resetErrors(); | ||
|  |         $this->tokens = @token_get_all($code); | ||
|  |         $this->handleErrors(); | ||
|  | 
 | ||
|  |         if (false !== $scream) { | ||
|  |             ini_set('xdebug.scream', $scream); | ||
|  |         } | ||
|  | 
 | ||
|  |         $this->code = $code; // keep the code around for __halt_compiler() handling
 | ||
|  |         $this->pos  = -1; | ||
|  |         $this->line =  1; | ||
|  |         $this->filePos = 0; | ||
|  |     } | ||
|  | 
 | ||
|  |     protected function resetErrors() { | ||
|  |         // set error_get_last() to defined state by forcing an undefined variable error
 | ||
|  |         set_error_handler(function() { return false; }, 0); | ||
|  |         @$undefinedVariable; | ||
|  |         restore_error_handler(); | ||
|  |     } | ||
|  | 
 | ||
|  |     protected function handleErrors() { | ||
|  |         $error = error_get_last(); | ||
|  | 
 | ||
|  |         if (preg_match( | ||
|  |             '~^Unterminated comment starting line ([0-9]+)$~', | ||
|  |             $error['message'], $matches | ||
|  |         )) { | ||
|  |             throw new Error('Unterminated comment', (int) $matches[1]); | ||
|  |         } | ||
|  | 
 | ||
|  |         if (preg_match( | ||
|  |             '~^Unexpected character in input:  \'(.)\' \(ASCII=([0-9]+)\)~s', | ||
|  |             $error['message'], $matches | ||
|  |         )) { | ||
|  |             throw new Error(sprintf( | ||
|  |                 'Unexpected character "%s" (ASCII %d)', | ||
|  |                 $matches[1], $matches[2] | ||
|  |             )); | ||
|  |         } | ||
|  | 
 | ||
|  |         // PHP cuts error message after null byte, so need special case
 | ||
|  |         if (preg_match('~^Unexpected character in input:  \'$~', $error['message'])) { | ||
|  |             throw new Error('Unexpected null byte'); | ||
|  |         } | ||
|  |     } | ||
|  | 
 | ||
|  |     /** | ||
|  |      * Fetches the next token. | ||
|  |      * | ||
|  |      * The available attributes are determined by the 'usedAttributes' option, which can | ||
|  |      * be specified in the constructor. The following attributes are supported: | ||
|  |      * | ||
|  |      *  * 'comments'      => Array of PhpParser\Comment or PhpParser\Comment\Doc instances, | ||
|  |      *                       representing all comments that occurred between the previous | ||
|  |      *                       non-discarded token and the current one. | ||
|  |      *  * 'startLine'     => Line in which the node starts. | ||
|  |      *  * 'endLine'       => Line in which the node ends. | ||
|  |      *  * 'startTokenPos' => Offset into the token array of the first token in the node. | ||
|  |      *  * 'endTokenPos'   => Offset into the token array of the last token in the node. | ||
|  |      *  * 'startFilePos'  => Offset into the code string of the first character that is part of the node. | ||
|  |      *  * 'endFilePos'    => Offset into the code string of the last character that is part of the node | ||
|  |      * | ||
|  |      * @param mixed $value           Variable to store token content in | ||
|  |      * @param mixed $startAttributes Variable to store start attributes in | ||
|  |      * @param mixed $endAttributes   Variable to store end attributes in | ||
|  |      * | ||
|  |      * @return int Token id | ||
|  |      */ | ||
|  |     public function getNextToken(&$value = null, &$startAttributes = null, &$endAttributes = null) { | ||
|  |         $startAttributes = array(); | ||
|  |         $endAttributes   = array(); | ||
|  | 
 | ||
|  |         while (1) { | ||
|  |             if (isset($this->tokens[++$this->pos])) { | ||
|  |                 $token = $this->tokens[$this->pos]; | ||
|  |             } else { | ||
|  |                 // EOF token with ID 0
 | ||
|  |                 $token = "\0"; | ||
|  |             } | ||
|  | 
 | ||
|  |             if (isset($this->usedAttributes['startTokenPos'])) { | ||
|  |                 $startAttributes['startTokenPos'] = $this->pos; | ||
|  |             } | ||
|  |             if (isset($this->usedAttributes['startFilePos'])) { | ||
|  |                 $startAttributes['startFilePos'] = $this->filePos; | ||
|  |             } | ||
|  | 
 | ||
|  |             if (is_string($token)) { | ||
|  |                 // bug in token_get_all
 | ||
|  |                 if ('b"' === $token) { | ||
|  |                     $value = 'b"'; | ||
|  |                     $this->filePos += 2; | ||
|  |                     $id = ord('"'); | ||
|  |                 } else { | ||
|  |                     $value = $token; | ||
|  |                     $this->filePos += 1; | ||
|  |                     $id = ord($token); | ||
|  |                 } | ||
|  | 
 | ||
|  |                 if (isset($this->usedAttributes['startLine'])) { | ||
|  |                     $startAttributes['startLine'] = $this->line; | ||
|  |                 } | ||
|  |                 if (isset($this->usedAttributes['endLine'])) { | ||
|  |                     $endAttributes['endLine'] = $this->line; | ||
|  |                 } | ||
|  |                 if (isset($this->usedAttributes['endTokenPos'])) { | ||
|  |                     $endAttributes['endTokenPos'] = $this->pos; | ||
|  |                 } | ||
|  |                 if (isset($this->usedAttributes['endFilePos'])) { | ||
|  |                     $endAttributes['endFilePos'] = $this->filePos - 1; | ||
|  |                 } | ||
|  | 
 | ||
|  |                 return $id; | ||
|  |             } else { | ||
|  |                 $this->line += substr_count($token[1], "\n"); | ||
|  |                 $this->filePos += strlen($token[1]); | ||
|  | 
 | ||
|  |                 if (T_COMMENT === $token[0]) { | ||
|  |                     if (isset($this->usedAttributes['comments'])) { | ||
|  |                         $startAttributes['comments'][] = new Comment($token[1], $token[2]); | ||
|  |                     } | ||
|  |                 } elseif (T_DOC_COMMENT === $token[0]) { | ||
|  |                     if (isset($this->usedAttributes['comments'])) { | ||
|  |                         $startAttributes['comments'][] = new Comment\Doc($token[1], $token[2]); | ||
|  |                     } | ||
|  |                 } elseif (!isset($this->dropTokens[$token[0]])) { | ||
|  |                     $value = $token[1]; | ||
|  | 
 | ||
|  |                     if (isset($this->usedAttributes['startLine'])) { | ||
|  |                         $startAttributes['startLine'] = $token[2]; | ||
|  |                     } | ||
|  |                     if (isset($this->usedAttributes['endLine'])) { | ||
|  |                         $endAttributes['endLine'] = $this->line; | ||
|  |                     } | ||
|  |                     if (isset($this->usedAttributes['endTokenPos'])) { | ||
|  |                         $endAttributes['endTokenPos'] = $this->pos; | ||
|  |                     } | ||
|  |                     if (isset($this->usedAttributes['endFilePos'])) { | ||
|  |                         $endAttributes['endFilePos'] = $this->filePos - 1; | ||
|  |                     } | ||
|  | 
 | ||
|  |                     return $this->tokenMap[$token[0]]; | ||
|  |                 } | ||
|  |             } | ||
|  |         } | ||
|  | 
 | ||
|  |         throw new \RuntimeException('Reached end of lexer loop'); | ||
|  |     } | ||
|  | 
 | ||
|  |     /** | ||
|  |      * Returns the token array for current code. | ||
|  |      * | ||
|  |      * The token array is in the same format as provided by the | ||
|  |      * token_get_all() function and does not discard tokens (i.e. | ||
|  |      * whitespace and comments are included). The token position | ||
|  |      * attributes are against this token array. | ||
|  |      * | ||
|  |      * @return array Array of tokens in token_get_all() format | ||
|  |      */ | ||
|  |     public function getTokens() { | ||
|  |         return $this->tokens; | ||
|  |     } | ||
|  | 
 | ||
|  |     /** | ||
|  |      * Handles __halt_compiler() by returning the text after it. | ||
|  |      * | ||
|  |      * @return string Remaining text | ||
|  |      */ | ||
|  |     public function handleHaltCompiler() { | ||
|  |         // text after T_HALT_COMPILER, still including ();
 | ||
|  |         $textAfter = substr($this->code, $this->filePos); | ||
|  | 
 | ||
|  |         // ensure that it is followed by ();
 | ||
|  |         // this simplifies the situation, by not allowing any comments
 | ||
|  |         // in between of the tokens.
 | ||
|  |         if (!preg_match('~^\s*\(\s*\)\s*(?:;|\?>\r?\n?)~', $textAfter, $matches)) { | ||
|  |             throw new Error('__HALT_COMPILER must be followed by "();"'); | ||
|  |         } | ||
|  | 
 | ||
|  |         // prevent the lexer from returning any further tokens
 | ||
|  |         $this->pos = count($this->tokens); | ||
|  | 
 | ||
|  |         // return with (); removed
 | ||
|  |         return (string) substr($textAfter, strlen($matches[0])); // (string) converts false to ''
 | ||
|  |     } | ||
|  | 
 | ||
|  |     /** | ||
|  |      * Creates the token map. | ||
|  |      * | ||
|  |      * The token map maps the PHP internal token identifiers | ||
|  |      * to the identifiers used by the Parser. Additionally it | ||
|  |      * maps T_OPEN_TAG_WITH_ECHO to T_ECHO and T_CLOSE_TAG to ';'. | ||
|  |      * | ||
|  |      * @return array The token map | ||
|  |      */ | ||
|  |     protected function createTokenMap() { | ||
|  |         $tokenMap = array(); | ||
|  | 
 | ||
|  |         // 256 is the minimum possible token number, as everything below
 | ||
|  |         // it is an ASCII value
 | ||
|  |         for ($i = 256; $i < 1000; ++$i) { | ||
|  |             if (T_DOUBLE_COLON === $i) { | ||
|  |                 // T_DOUBLE_COLON is equivalent to T_PAAMAYIM_NEKUDOTAYIM
 | ||
|  |                 $tokenMap[$i] = Parser::T_PAAMAYIM_NEKUDOTAYIM; | ||
|  |             } elseif(T_OPEN_TAG_WITH_ECHO === $i) { | ||
|  |                 // T_OPEN_TAG_WITH_ECHO with dropped T_OPEN_TAG results in T_ECHO
 | ||
|  |                 $tokenMap[$i] = Parser::T_ECHO; | ||
|  |             } elseif(T_CLOSE_TAG === $i) { | ||
|  |                 // T_CLOSE_TAG is equivalent to ';'
 | ||
|  |                 $tokenMap[$i] = ord(';'); | ||
|  |             } elseif ('UNKNOWN' !== $name = token_name($i)) { | ||
|  |                 if ('T_HASHBANG' === $name) { | ||
|  |                     // HHVM uses a special token for #! hashbang lines
 | ||
|  |                     $tokenMap[$i] = Parser::T_INLINE_HTML; | ||
|  |                 } else if (defined($name = 'PhpParser\Parser::' . $name)) { | ||
|  |                     // Other tokens can be mapped directly
 | ||
|  |                     $tokenMap[$i] = constant($name); | ||
|  |                 } | ||
|  |             } | ||
|  |         } | ||
|  | 
 | ||
|  |         // HHVM uses a special token for numbers that overflow to double
 | ||
|  |         if (defined('T_ONUMBER')) { | ||
|  |             $tokenMap[T_ONUMBER] = Parser::T_DNUMBER; | ||
|  |         } | ||
|  |         // HHVM also has a separate token for the __COMPILER_HALT_OFFSET__ constant
 | ||
|  |         if (defined('T_COMPILER_HALT_OFFSET')) { | ||
|  |             $tokenMap[T_COMPILER_HALT_OFFSET] = Parser::T_STRING; | ||
|  |         } | ||
|  | 
 | ||
|  |         return $tokenMap; | ||
|  |     } | ||
|  | } |