100 lines
4.0 KiB
PHP
100 lines
4.0 KiB
PHP
|
<?php
|
||
|
|
||
|
/*
|
||
|
* This file is part of the Symfony package.
|
||
|
*
|
||
|
* (c) Fabien Potencier <fabien@symfony.com>
|
||
|
*
|
||
|
* For the full copyright and license information, please view the LICENSE
|
||
|
* file that was distributed with this source code.
|
||
|
*/
|
||
|
|
||
|
namespace Symfony\Component\ExpressionLanguage;
|
||
|
|
||
|
/**
|
||
|
* Lexes an expression.
|
||
|
*
|
||
|
* @author Fabien Potencier <fabien@symfony.com>
|
||
|
*/
|
||
|
class Lexer
|
||
|
{
|
||
|
/**
|
||
|
* Tokenizes an expression.
|
||
|
*
|
||
|
* @throws SyntaxError
|
||
|
*/
|
||
|
public function tokenize(string $expression): TokenStream
|
||
|
{
|
||
|
$expression = str_replace(["\r", "\n", "\t", "\v", "\f"], ' ', $expression);
|
||
|
$cursor = 0;
|
||
|
$tokens = [];
|
||
|
$brackets = [];
|
||
|
$end = \strlen($expression);
|
||
|
|
||
|
while ($cursor < $end) {
|
||
|
if (' ' == $expression[$cursor]) {
|
||
|
++$cursor;
|
||
|
|
||
|
continue;
|
||
|
}
|
||
|
|
||
|
if (preg_match('/[0-9]+(?:\.[0-9]+)?([Ee][\+\-][0-9]+)?/A', $expression, $match, 0, $cursor)) {
|
||
|
// numbers
|
||
|
$number = (float) $match[0]; // floats
|
||
|
if (preg_match('/^[0-9]+$/', $match[0]) && $number <= \PHP_INT_MAX) {
|
||
|
$number = (int) $match[0]; // integers lower than the maximum
|
||
|
}
|
||
|
$tokens[] = new Token(Token::NUMBER_TYPE, $number, $cursor + 1);
|
||
|
$cursor += \strlen($match[0]);
|
||
|
} elseif (str_contains('([{', $expression[$cursor])) {
|
||
|
// opening bracket
|
||
|
$brackets[] = [$expression[$cursor], $cursor];
|
||
|
|
||
|
$tokens[] = new Token(Token::PUNCTUATION_TYPE, $expression[$cursor], $cursor + 1);
|
||
|
++$cursor;
|
||
|
} elseif (str_contains(')]}', $expression[$cursor])) {
|
||
|
// closing bracket
|
||
|
if (empty($brackets)) {
|
||
|
throw new SyntaxError(sprintf('Unexpected "%s".', $expression[$cursor]), $cursor, $expression);
|
||
|
}
|
||
|
|
||
|
[$expect, $cur] = array_pop($brackets);
|
||
|
if ($expression[$cursor] != strtr($expect, '([{', ')]}')) {
|
||
|
throw new SyntaxError(sprintf('Unclosed "%s".', $expect), $cur, $expression);
|
||
|
}
|
||
|
|
||
|
$tokens[] = new Token(Token::PUNCTUATION_TYPE, $expression[$cursor], $cursor + 1);
|
||
|
++$cursor;
|
||
|
} elseif (preg_match('/"([^"\\\\]*(?:\\\\.[^"\\\\]*)*)"|\'([^\'\\\\]*(?:\\\\.[^\'\\\\]*)*)\'/As', $expression, $match, 0, $cursor)) {
|
||
|
// strings
|
||
|
$tokens[] = new Token(Token::STRING_TYPE, stripcslashes(substr($match[0], 1, -1)), $cursor + 1);
|
||
|
$cursor += \strlen($match[0]);
|
||
|
} elseif (preg_match('/(?<=^|[\s(])not in(?=[\s(])|\!\=\=|(?<=^|[\s(])not(?=[\s(])|(?<=^|[\s(])and(?=[\s(])|\=\=\=|\>\=|(?<=^|[\s(])or(?=[\s(])|\<\=|\*\*|\.\.|(?<=^|[\s(])in(?=[\s(])|&&|\|\||(?<=^|[\s(])matches|\=\=|\!\=|\*|~|%|\/|\>|\||\!|\^|&|\+|\<|\-/A', $expression, $match, 0, $cursor)) {
|
||
|
// operators
|
||
|
$tokens[] = new Token(Token::OPERATOR_TYPE, $match[0], $cursor + 1);
|
||
|
$cursor += \strlen($match[0]);
|
||
|
} elseif (str_contains('.,?:', $expression[$cursor])) {
|
||
|
// punctuation
|
||
|
$tokens[] = new Token(Token::PUNCTUATION_TYPE, $expression[$cursor], $cursor + 1);
|
||
|
++$cursor;
|
||
|
} elseif (preg_match('/[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*/A', $expression, $match, 0, $cursor)) {
|
||
|
// names
|
||
|
$tokens[] = new Token(Token::NAME_TYPE, $match[0], $cursor + 1);
|
||
|
$cursor += \strlen($match[0]);
|
||
|
} else {
|
||
|
// unlexable
|
||
|
throw new SyntaxError(sprintf('Unexpected character "%s".', $expression[$cursor]), $cursor, $expression);
|
||
|
}
|
||
|
}
|
||
|
|
||
|
$tokens[] = new Token(Token::EOF_TYPE, null, $cursor + 1);
|
||
|
|
||
|
if (!empty($brackets)) {
|
||
|
[$expect, $cur] = array_pop($brackets);
|
||
|
throw new SyntaxError(sprintf('Unclosed "%s".', $expect), $cur, $expression);
|
||
|
}
|
||
|
|
||
|
return new TokenStream($tokens, $expression);
|
||
|
}
|
||
|
}
|