Revert "Match using non-capturing groups only"

src/Tokenizer.php

@@ -4,19 +4,15 @@
 
 namespace Doctrine\SqlFormatter;
 
-use function array_flip;
 use function array_key_last;
-use function array_keys;
 use function array_map;
+use function array_pop;
 use function assert;
 use function count;
 use function implode;
 use function is_int;
-use function is_string;
 use function preg_match;
 use function preg_quote;
-use function preg_replace;
-use function preg_replace_callback;
 use function reset;
 use function str_replace;
 use function str_starts_with;
@@ -726,12 +722,8 @@ final class Tokenizer
         'YEARWEEK',
     ];
 
-    /**
-     * Regular expression for tokenizing.
-     *
-     * @var array{string, array<int, string>}
-     */
-    private readonly array $tokenizeRegex;
+    /** Regular expression for tokenizing. */
+    private readonly string $tokenizeRegex;
 
     /**
      * Punctuation that can be used as a boundary between other tokens
@@ -767,8 +759,7 @@ final class Tokenizer
     public function __construct()
     {
         $regexes             = $this->makeTokenizeRegexes();
-        $regex               = $this->makeTokenizeRegex($regexes);
-        $this->tokenizeRegex = $this->removeNamedGroupsFromRegex($regex);
+        $this->tokenizeRegex = $this->makeTokenizeRegex($regexes);
     }
 
     /**
@@ -897,47 +888,7 @@ private function makeTokenizeRegex(array $regexes): string
             $parts[] = '(?<t_' . $type . '>' . $regex . ')';
         }
 
-        return '~\G(?>' . implode('|', $parts) . ')~';
-    }
-
-    /**
-     * Workaround slow PCRE named groups - https://github.com/php/php-src/issues/14423.
-     *
-     * Revert/remove once PHP 8.3 support is dropped.
-     *
-     * @return array{string, array<int, string>}
-     */
-    private function removeNamedGroupsFromRegex(string $regex): array
-    {
-        // make sure the original regex cannot be satisfied and append one unnamed capturing group
-        // to discover all named capturing groups
-        $regexForAnalysis = preg_replace('~^(.)(.*)(\1\w*$)~s', '$1(?:(?=1)0$2)|()$3', $regex);
-        assert($regexForAnalysis !== null);
-        preg_match($regexForAnalysis, '', $matches);
-        assert(count($matches) > 1);
-
-        $regexIndexToName = [];
-        $prevK            = null;
-        foreach (array_keys($matches) as $k) {
-            if (is_string($prevK)) {
-                $regexIndexToName[$k] = $prevK;
-            }
-
-            $prevK = $k;
-        }
-
-        // remap named groups to unnamed
-        $namedGroupsRegex        = '(?:' . implode('|', array_map(static fn ($v) => preg_quote($v, '~'), $regexIndexToName)) . ')';
-        $regexWithoutNamedGroups = preg_replace('~(?<=\()\?<' . $namedGroupsRegex . '>~', '', $regex);
-        assert($regexWithoutNamedGroups !== null);
-        $regexWithoutNamedGroups = preg_replace_callback(
-            '~(?<=\(\?)&' . $namedGroupsRegex . '(?=\))~',
-            static fn ($matches) => array_flip($regexIndexToName)[substr($matches[0], 1)],
-            $regexWithoutNamedGroups,
-        );
-        assert($regexWithoutNamedGroups !== null);
-
-        return [$regexWithoutNamedGroups, $regexIndexToName];
+        return '~\G(?:' . implode('|', $parts) . ')~';
     }
 
     /**
@@ -956,14 +907,17 @@ public function tokenize(string $string): Cursor
 
         while ($offset < strlen($string)) {
             // Get the next token and the token type
-            preg_match($tokenizeRegex[0], $upper, $matches, 0, $offset);
+            preg_match($tokenizeRegex, $upper, $matches, 0, $offset);
             assert(($matches[0] ?? '') !== '');
 
-            $lastMatchesNamedGroup = $tokenizeRegex[1][array_key_last($matches)];
-            assert(str_starts_with($lastMatchesNamedGroup, 't_'));
+            while (is_int($lastMatchesKey = array_key_last($matches))) {
+                array_pop($matches);
+            }
+
+            assert(str_starts_with($lastMatchesKey, 't_'));
 
             /** @var Token::TOKEN_TYPE_* $tokenType */
-            $tokenType = (int) substr($lastMatchesNamedGroup, 2);
+            $tokenType = (int) substr($lastMatchesKey, 2);
 
             $token = new Token($tokenType, substr($string, $offset, strlen($matches[0])));