Assign to property by reference ignores functionMap.php

[jlherren]

Bug report

When a class property is assigned via a function that takes a reference, the type specified in functionMap.php seems to not be taken into account. Or at least it's the case with proc_open(). Although I'm not sure if the types given in functionMap.php are understood to be equivalent to @param-out.

functionMap.php:

'proc_open' => ['resource|false', 'command'=>'string', 'descriptorspec'=>'array', '&w_pipes'=>'resource[]', 'cwd='=>'?string', 'env='=>'?array', 'other_options='=>'array'],

Code snippet that reproduces the problem

https://phpstan.org/r/a76b47ab-8e57-40da-b76e-60fd02c2470e

Expected output

No error.

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[ondrejmirtes]

This one is tricky. Basically my fear is that for by-ref parameters, those types in functionMap don't mean anything. I don't want to research that now, but the problem is that for some functions, these types do not enforce the incoming type, and for some functions, these types are different from those assigned by-ref when the function call ends.

That's why "isBuiltin" is mentioned in these places:

• https://github.com/phpstan/phpstan-src/blob/b009a445bd3d96013d02746109d6ebd777275da4/src/Rules/FunctionCallParametersCheck.php#L327
• https://github.com/phpstan/phpstan-src/blob/b009a445bd3d96013d02746109d6ebd777275da4/src/Analyser/NodeScopeResolver.php#L4740-L4750

My bet is that if you remove those conditions, some tests will fail, and you'll see why.

The path forward for this issue and #11791 is definitely a stub with @param-out :)

[piotrekkr]

I tied this param-out stub and it did not work but maybe I dont get how to work with it. I tried here https://phpstan.org/r/df08d92f-b46e-45c5-88fe-4235a42a0bf6 this

<?php declare(strict_types = 1);

$openSslSignature = '';
/**
 * @param-out string &$openSslSignature
 */
openssl_sign(
    'data',
    $openSslSignature,
    'key contents',
    'SHA256',
);

PHPStan\dumpType($openSslSignature);

with and without&. Still I get same mixed type. How should I use this @param-out? @ondrejmirtes

[ondrejmirtes]

Register the signature as a stub file and send a PR to phpstan-src: https://phpstan.org/user-guide/stub-files

[piotrekkr]

@ondrejmirtes Done here phpstan/phpstan-src#3532