www.gusucode.com > KPPW众包威客PHP开源建站系统 v3.0源码程序 > KPPW/vendor/nikic/php-parser/lib/PhpParser/Lexer/Emulative.php
<?php
namespace PhpParser\Lexer;
use PhpParser\Parser\Tokens;
/**
* ATTENTION: This code is WRITE-ONLY. Do not try to read it.
*/
class Emulative extends \PhpParser\Lexer
{
protected $newKeywords;
protected $inObjectAccess;
const T_ELLIPSIS = 1001;
const T_POW = 1002;
const T_POW_EQUAL = 1003;
const T_COALESCE = 1004;
const T_SPACESHIP = 1005;
const T_YIELD_FROM = 1006;
const PHP_7_0 = '7.0.0dev';
const PHP_5_6 = '5.6.0rc1';
const PHP_5_5 = '5.5.0beta1';
public function __construct(array $options = array()) {
parent::__construct($options);
$newKeywordsPerVersion = array(
self::PHP_5_5 => array(
'finally' => Tokens::T_FINALLY,
'yield' => Tokens::T_YIELD,
),
);
$this->newKeywords = array();
foreach ($newKeywordsPerVersion as $version => $newKeywords) {
if (version_compare(PHP_VERSION, $version, '>=')) {
break;
}
$this->newKeywords += $newKeywords;
}
if (version_compare(PHP_VERSION, self::PHP_7_0, '>=')) {
return;
}
$this->tokenMap[self::T_COALESCE] = Tokens::T_COALESCE;
$this->tokenMap[self::T_SPACESHIP] = Tokens::T_SPACESHIP;
$this->tokenMap[self::T_YIELD_FROM] = Tokens::T_YIELD_FROM;
if (version_compare(PHP_VERSION, self::PHP_5_6, '>=')) {
return;
}
$this->tokenMap[self::T_ELLIPSIS] = Tokens::T_ELLIPSIS;
$this->tokenMap[self::T_POW] = Tokens::T_POW;
$this->tokenMap[self::T_POW_EQUAL] = Tokens::T_POW_EQUAL;
}
public function startLexing($code) {
$this->inObjectAccess = false;
$preprocessedCode = $this->preprocessCode($code);
parent::startLexing($preprocessedCode);
if ($preprocessedCode !== $code) {
$this->postprocessTokens();
}
// Set code property back to the original code, so __halt_compiler()
// handling and (start|end)FilePos attributes use the correct offsets
$this->code = $code;
}
/*
* Replaces new features in the code by ~__EMU__{NAME}__{DATA}__~ sequences.
* ~LABEL~ is never valid PHP code, that's why we can (to some degree) safely
* use it here.
* Later when preprocessing the tokens these sequences will either be replaced
* by real tokens or replaced with their original content (e.g. if they occurred
* inside a string, i.e. a place where they don't have a special meaning).
*/
protected function preprocessCode($code) {
if (version_compare(PHP_VERSION, self::PHP_7_0, '>=')) {
return $code;
}
$code = str_replace('??', '~__EMU__COALESCE__~', $code);
$code = str_replace('<=>', '~__EMU__SPACESHIP__~', $code);
$code = preg_replace_callback('(yield[ \n\r\t]+from)', function($matches) {
// Encoding $0 in order to preserve exact whitespace
return '~__EMU__YIELDFROM__' . bin2hex($matches[0]) . '__~';
}, $code);
if (version_compare(PHP_VERSION, self::PHP_5_6, '>=')) {
return $code;
}
$code = str_replace('...', '~__EMU__ELLIPSIS__~', $code);
$code = preg_replace('((?<!/)\*\*=)', '~__EMU__POWEQUAL__~', $code);
$code = preg_replace('((?<!/)\*\*(?!/))', '~__EMU__POW__~', $code);
return $code;
}
/*
* Replaces the ~__EMU__...~ sequences with real tokens or their original
* value.
*/
protected function postprocessTokens() {
// we need to manually iterate and manage a count because we'll change
// the tokens array on the way
for ($i = 0, $c = count($this->tokens); $i < $c; ++$i) {
// first check that the following tokens are of form ~LABEL~,
// then match the __EMU__... sequence.
if ('~' === $this->tokens[$i]
&& isset($this->tokens[$i + 2])
&& '~' === $this->tokens[$i + 2]
&& T_STRING === $this->tokens[$i + 1][0]
&& preg_match('(^__EMU__([A-Z]++)__(?:([A-Za-z0-9]++)__)?$)', $this->tokens[$i + 1][1], $matches)
) {
if ('ELLIPSIS' === $matches[1]) {
$replace = array(
array(self::T_ELLIPSIS, '...', $this->tokens[$i + 1][2])
);
} else if ('POW' === $matches[1]) {
$replace = array(
array(self::T_POW, '**', $this->tokens[$i + 1][2])
);
} else if ('POWEQUAL' === $matches[1]) {
$replace = array(
array(self::T_POW_EQUAL, '**=', $this->tokens[$i + 1][2])
);
} else if ('COALESCE' === $matches[1]) {
$replace = array(
array(self::T_COALESCE, '??', $this->tokens[$i + 1][2])
);
} else if ('SPACESHIP' === $matches[1]) {
$replace = array(
array(self::T_SPACESHIP, '<=>', $this->tokens[$i + 1][2]),
);
} else if ('YIELDFROM' === $matches[1]) {
$content = hex2bin($matches[2]);
$replace = array(
array(self::T_YIELD_FROM, $content, $this->tokens[$i + 1][2] - substr_count($content, "\n"))
);
} else {
throw new \RuntimeException('Invalid __EMU__ sequence');
}
array_splice($this->tokens, $i, 3, $replace);
$c -= 3 - count($replace);
// for multichar tokens (e.g. strings) replace any ~__EMU__...~ sequences
// in their content with the original character sequence
} elseif (is_array($this->tokens[$i])
&& 0 !== strpos($this->tokens[$i][1], '__EMU__')
) {
$this->tokens[$i][1] = preg_replace_callback(
'(~__EMU__([A-Z]++)__(?:([A-Za-z0-9]++)__)?~)',
array($this, 'restoreContentCallback'),
$this->tokens[$i][1]
);
}
}
}
/*
* This method is a callback for restoring EMU sequences in
* multichar tokens (like strings) to their original value.
*/
public function restoreContentCallback(array $matches) {
if ('ELLIPSIS' === $matches[1]) {
return '...';
} else if ('POW' === $matches[1]) {
return '**';
} else if ('POWEQUAL' === $matches[1]) {
return '**=';
} else if ('COALESCE' === $matches[1]) {
return '??';
} else if ('SPACESHIP' === $matches[1]) {
return '<=>';
} else if ('YIELDFROM' === $matches[1]) {
return hex2bin($matches[2]);
} else {
return $matches[0];
}
}
public function getNextToken(&$value = null, &$startAttributes = null, &$endAttributes = null) {
$token = parent::getNextToken($value, $startAttributes, $endAttributes);
// replace new keywords by their respective tokens. This is not done
// if we currently are in an object access (e.g. in $obj->namespace
// "namespace" stays a T_STRING tokens and isn't converted to T_NAMESPACE)
if (Tokens::T_STRING === $token && !$this->inObjectAccess) {
if (isset($this->newKeywords[strtolower($value)])) {
return $this->newKeywords[strtolower($value)];
}
} else {
// keep track of whether we currently are in an object access (after ->)
$this->inObjectAccess = Tokens::T_OBJECT_OPERATOR === $token;
}
return $token;
}
}