Broken Function: get_cfg_var

[acabal]

Function URL

https://www.php.net/manual/en/function.get-cfg-var.php

PHP Version

8.4

Safe Version

3.0.2

Description

If Safe\get_cfg_var() is called with a value that does not exist in the current configuration, it crashes PHPStan with an uncaught exception.

Example:

Use Safe\get_cfg_var;

get_cfg_var('does not exist');

$> ./vendor/bin/phpstan
Fatal error: Uncaught Safe\Exceptions\InfoException: An error occurred in /path/to/project/vendor/thecodingmachine/safe/generated/Exceptions/InfoException.php:9
Stack trace:
#0 /path/to/project/vendor/thecodingmachine/safe/generated/8.1/info.php(228): Safe\Exceptions\InfoException::createFromPhpError()
#1 /path/to/project/file.php(3): Safe\get_cfg_var()
#2 /path/to/project/vendor/composer/autoload_real.php(41): require('...')
#3 /path/to/project/vendor/composer/autoload_real.php(45): {closure}()
#4 /path/to/project/vendor/autoload.php(25): ComposerAutoloaderInit1cc678e3a0a52264b4c2205084c653d4::getLoader()
#5 phar:///path/to/project/vendor/phpstan/phpstan/phpstan.phar/bin/phpstan(55): require_once('...')
#6 phar:///path/to/project/vendor/phpstan/phpstan/phpstan.phar/bin/phpstan(115): _PHPStan_24e2736d6\{closure}()
#7 /path/to/project/vendor/phpstan/phpstan/phpstan(8): require('...')
#8 /path/to/project/vendor/bin/phpstan(119): include('...')
#9 {main}
  thrown in /path/to/project/vendor/thecodingmachine/safe/generated/Exceptions/InfoException.php on line 9

Compare the base function for which PHPStan works as expected:

\get_cfg_var('does not exist');

$> ./vendor/bin/phpstan
------ ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- 
  Line   lib/Constants.php                                                                                                                                                                                                                          
 ------ ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- 
  1     Function get_cfg_var is unsafe to use. It can return FALSE instead of throwing an exception. Please add 'use function Safe\get_cfg_var;' at the beginning of the file to use the variant provided by the 'thecodingmachine/safe' library.  
         🪪  theCodingMachineSafe.function                                                                                                                                                                                                          
 ------ -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

[shish]

This is very weird... firstly I'm unable to reproduce the issue; secondly I can't even imagine how this can happen, since phpstan is a static analyser (ie, it looks at the code, it doesn't run it), and throwing Safe\Exceptions\InfoException should only happen when the code gets run o_O

[acabal]

This instance of get_cfg_var() is in a file which is included by Composer automatically via the autoload-dev['files'] and autoload['files' configuration options, so maybe that has something to do with it? Composer's autoloader is initialized in #4 of the stack trace.

[acabal]

I suppose if the file is autoincluded and does throw an exception when run, then it would crash PHPStan. But somehow that seems like a less than ideal outcome when as you mentioned it's not expected for code to be executed. Not sure if that's more of a PHPStan issue.

[shish]

Looking at the stack track I'm curious about

#1 /path/to/project/file.php(3): Safe\get_cfg_var()

Looks like PHPStan autoloads all files in the autoload list (which is how php autoloading works), and one of those is project/file.php, and that file is executing code at import-time, and that code calls a Safe function with invalid input, which throws an exception.

Safe functions throwing an exception with invalid input is working-as-intended.

What is this file, why is it in the autoload list, and why is it running broken code at import-time?

[acabal]

Yes after looking at this more closely this is probably just expected behavior but could benefit from a better presentation to the user from PHPStan.

The file is a file with global constants which is autoincluded by Composer so that its symbols can be discovered by PHPStan.

[acabal]

Tangentially related, the PHPDoc for Safe\get_cfg_var() still states that it returns false on error, but that's not true anymore.