<?php declare(strict_types=1);
namespace PhpParser\Lexer\TokenEmulator;
use PhpParser\Lexer\Emulative;
final class CoaleseEqualTokenEmulator extends TokenEmulator
{
public function getPhpVersion(): string
{
return Emulative::PHP_7_4;
}
public function isEmulationNeeded(string $code): bool
{
return strpos($code, '??=') !== false;
}
public function emulate(string $code, array $tokens): array
{
// We need to manually iterate and manage a count because we'll change
// the tokens array on the way
$line = 1;
for ($i = 0, $c = count($tokens); $i < $c; ++$i) {
if (isset($tokens[$i + 1])) {
if ($tokens[$i][0] === T_COALESCE && $tokens[$i + 1] === '=') {
array_splice($tokens, $i, 2, [
[\T_COALESCE_EQUAL, '??=', $line]
]);
$c--;
continue;
}
}
if (\is_array($tokens[$i])) {
$line += substr_count($tokens[$i][1], "\n");
}
}
return $tokens;
}
public function reverseEmulate(string $code, array $tokens): array
{
// ??= was not valid code previously, don't bother.
return $tokens;
}
}