1<?php declare(strict_types=1); 2 3namespace PhpParser\Lexer\TokenEmulator; 4 5use PhpParser\Lexer\Emulative; 6 7final class NullsafeTokenEmulator extends TokenEmulator 8{ 9 public function getPhpVersion(): string 10 { 11 return Emulative::PHP_8_0; 12 } 13 14 public function isEmulationNeeded(string $code): bool 15 { 16 return strpos($code, '?->') !== false; 17 } 18 19 public function emulate(string $code, array $tokens): array 20 { 21 // We need to manually iterate and manage a count because we'll change 22 // the tokens array on the way 23 $line = 1; 24 for ($i = 0, $c = count($tokens); $i < $c; ++$i) { 25 if ($tokens[$i] === '?' && isset($tokens[$i + 1]) && $tokens[$i + 1][0] === \T_OBJECT_OPERATOR) { 26 array_splice($tokens, $i, 2, [ 27 [\T_NULLSAFE_OBJECT_OPERATOR, '?->', $line] 28 ]); 29 $c--; 30 continue; 31 } 32 33 // Handle ?-> inside encapsed string. 34 if ($tokens[$i][0] === \T_ENCAPSED_AND_WHITESPACE && isset($tokens[$i - 1]) 35 && $tokens[$i - 1][0] === \T_VARIABLE 36 && preg_match('/^\?->([a-zA-Z_\x80-\xff][a-zA-Z0-9_\x80-\xff]*)/', $tokens[$i][1], $matches) 37 ) { 38 $replacement = [ 39 [\T_NULLSAFE_OBJECT_OPERATOR, '?->', $line], 40 [\T_STRING, $matches[1], $line], 41 ]; 42 if (\strlen($matches[0]) !== \strlen($tokens[$i][1])) { 43 $replacement[] = [ 44 \T_ENCAPSED_AND_WHITESPACE, 45 \substr($tokens[$i][1], \strlen($matches[0])), 46 $line 47 ]; 48 } 49 array_splice($tokens, $i, 1, $replacement); 50 $c += \count($replacement) - 1; 51 continue; 52 } 53 54 if (\is_array($tokens[$i])) { 55 $line += substr_count($tokens[$i][1], "\n"); 56 } 57 } 58 59 return $tokens; 60 } 61 62 public function reverseEmulate(string $code, array $tokens): array 63 { 64 // ?-> was not valid code previously, don't bother. 65 return $tokens; 66 } 67} 68