Incorrect return types for stubbed core functions depending on PHP version

[kkmuffme]

https://psalm.dev/r/7106f13383

in PHP 8 vsprintf will never return false, but in PHP 7 it will.
As discussed in #9877 (comment) the stubs will never fall back to the callmap - this makes declaring different return/param types between PHP versions impossible in psalm.

I suggest to change it to fall back from the stubs to the callmap if the param/return type is not declared in the stubs (but is in the callmap)

Also somehow related to #9843 since atm no consistency checking happens in-between the different versions of the callmap and the stubs either

[psalm-github-bot]

I found these snippets:

https://psalm.dev/r/7106f13383

<?php

$x = vsprintf( 'a', array() );
/** @psalm-trace $x */;

Psalm output (using commit 99a54fb):

INFO: Trace - 4:23 - $x: false|string

INFO: UnusedVariable - 3:1 - $x is never referenced or the value is not used

[ygottschalk]

I thought that we have the files stubs/Php8X.phpstub for that...

[orklah]

I thought that we have the files stubs/Php8X.phpstub for that...

Yeah, that is a first option. We also have this:

psalm/stubs/CoreGenericFunctions.phpstub

Line 66 in bd0ba6e

* PHP_MAJOR_VERSION is 8 ?

For anything that those two tools can't answer, TypeProviders are the go to.