1<?php declare(strict_types=1); 2 3namespace PhpParser\Lexer\TokenEmulator; 4 5use PhpParser\Lexer\Emulative; 6 7final class CoaleseEqualTokenEmulator extends TokenEmulator 8{ 9 public function getPhpVersion(): string 10 { 11 return Emulative::PHP_7_4; 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 (isset($tokens[$i + 1])) { 26 if ($tokens[$i][0] === T_COALESCE && $tokens[$i + 1] === '=') { 27 array_splice($tokens, $i, 2, [ 28 [\T_COALESCE_EQUAL, '??=', $line] 29 ]); 30 $c--; 31 continue; 32 } 33 } 34 if (\is_array($tokens[$i])) { 35 $line += substr_count($tokens[$i][1], "\n"); 36 } 37 } 38 39 return $tokens; 40 } 41 42 public function reverseEmulate(string $code, array $tokens): array 43 { 44 // ??= was not valid code previously, don't bother. 45 return $tokens; 46 } 47} 48