[9.x] Fix PHP warnings when rendering long blade string

[a-bashtannik]

\Illuminate\View\Component::resolveView checks the string for being a file

$factory->exists($view) ? $view : $this->createBladeViewFromString($factory, $view);

by calling \Illuminate\Filesystem\Filesystem::exists method, which is a pure standard file_exists function.

PHP has a hard limit on path length as defined by the constant PHP_MAXPATHLEN which depends on the operating system (Windows 260 characters, Unix: as specified in the c-runtime - on Linux this is PATH_MAX in limits.h being 4096).

PHP detects the program is trying to check plain file existence and calls php_check_open_basedir

1. https://github.com/php/php-src/blob/master/ext/standard/filestat.c#L757

If the PHP configuration has no open_basedir value, then another method virtual_file_ex will be called:

1. https://github.com/php/php-src/blob/master/main/fopen_wrappers.c#L282
2. https://github.com/php/php-src/blob/master/ext/standard/filestat.c#L767
3. https://github.com/php/php-src/blob/master/Zend/zend_virtual_cwd.c#L1008

But virtual_file_ex doesn't throw warnings, just returns false.

If open_basedir is configured, php_check_open_basedir_ex is called, it cares about open_basedir and throws a warning, otherwise file_exists just returns false. The program behavior depends of open_basedir setting.

Although it's OK in the PHP design paradigm, users meet problems from time to time having this warning, see #32254 #41745 livewire/livewire#918

This PR adds PHP_MAXPATHLEN check before calling file_exists.

Although I can add a test case for different open_basedir states, it will affect other tests running in parallel, and considering the issue is rare, I don't think there is a sense to make a custom php.ini environment for the case.

[taylorotwell]

Thanks for the PR, but can you succinctly describe the before / after behavior of this PR?

[a-bashtannik]

@taylorotwell Sure

Blade::render(string $string, array $data = [], bool $deleteCachedView = false)

❌ Before:

$string argument may be a raw blade template string (e.g. from the database) or a file path. If the length > PHP_MAXPATHLEN Blade::render fails because file_exists function throws a warning and createBladeViewFromString method is never called even if $string argument is a valid, but long blade template string.

✅ After

$string argument may have length > PHP_MAXPATHLEN, and considering it's impossible to have a file on the path with length > PHP_MAXPATHLEN, file_exists call is omitted, createBladeViewFromString is called and Blade::render returns compiled blade template as expected.

[taylorotwell]

Thanks!