Description
end() followed by next() leaves the internal pointer past the end, so key() returns NULL. A copy-on-write separation then moves it back to the first element instead of leaving it past the end. An in-range pointer survives the same separation unchanged, and the untouched copy keeps NULL, so the past-the-end case is the only one that moves.
The following code:
<?php
$a = ['a' => 1, 'b' => 2, 'c' => 3];
end($a);
next($a);
var_dump(key($a), current($a));
$b = $a;
$a['d'] = 4;
var_dump(key($a), current($a));
Resulted in this output:
NULL
bool(false)
string(1) "a"
int(1)
But I expected this output instead:
NULL
bool(false)
NULL
bool(false)
zend_array_dup() clamps the copied pointer with (source->nInternalPointer < source->nNumUsed) ? source->nInternalPointer : 0 at Zend/zend_hash.c:2511 for the mixed case and :2495 for the packed case. The immutable branch at :2479 copies it verbatim, so the three arms of that function disagree.
PHP Version
PHP 8.4.25, also PHP-8.4 and master at d26d5f2
Operating System
Linux
Description
end()followed bynext()leaves the internal pointer past the end, sokey()returns NULL. A copy-on-write separation then moves it back to the first element instead of leaving it past the end. An in-range pointer survives the same separation unchanged, and the untouched copy keeps NULL, so the past-the-end case is the only one that moves.The following code:
Resulted in this output:
But I expected this output instead:
zend_array_dup()clamps the copied pointer with(source->nInternalPointer < source->nNumUsed) ? source->nInternalPointer : 0atZend/zend_hash.c:2511for the mixed case and:2495for the packed case. The immutable branch at:2479copies it verbatim, so the three arms of that function disagree.PHP Version
PHP 8.4.25, also PHP-8.4 and master at d26d5f2
Operating System
Linux