Description

The following code:

<?php
// file: bug.php

$content = file_get_contents(__FILE__);
file_put_contents('newfile.php', $content."\n//");
var_dump(rename('newfile.php', __FILE__));

Resulted in this output:

PHP Warning:  rename(newfile.php,C:\Users\John\projects\test\bug.php): Access is denied (code: 5) in C:\Users\John\projects\test\bug.php on line 6

Warning: rename(newfile.php,C:\Users\John\projects\test\bug.php): Access is denied (code: 5) in C:\Users\John\projects\test\bug.php on line 6
bool(false)

But I expected this output instead:

bool(true)

This code mimics how Composer self updates (https://getcomposer.org/doc/03-cli.md#self-update-selfupdate-) and has obviously worked for many years, but is broken on Windows PHP 8.1: composer/composer#10444

Note that on Composer 2 we now use copy on Windows (to get around potential permission issues in UAC protected locations) and this still works on PHP 8.1, but Composer 1 uses rename (as do all non-Windows platforms on all Composer versions).

Fortunately, this appears to be a Windows only thing, as per this demo: https://github.com/johnstevenson/php-rename-bug/actions/runs/1669358275

PHP Version

PHP 8.1.0

Operating System

Windows 10