Revert passing script variables by reference

[Mark-H]

What does it do?

#15578 added the EXTR_REFS flag to the extract() function in modScript::process with the intention of allowing plugins to manipulated variables passed in to it.

This PR reverts that back to how it was in 2.x.

Why is it needed?

Unfortunately per https://community.modx.com/t/spform-how-to-change-language/4917/16 the pass by reference is causing issues when local variables in a snippet share the name of a script property or a copy of $scriptProperties is made. This is causing wildly unexpected results.

How to test

Two very simple snippets to reproduce the behavior are provided in the forum, both assuming the snippet is called with [[!mySnippet? &my_prop=`A`]]:

<?php
$my_prop = 'B';
return $scriptProperties['my_prop']; // returns 'B'

<?php
$newArr = $scriptProperties;
$newArr['my_prop'] = 'B';

return $scriptProperties['my_prop']; // returns 'B'

The expected result, because there is no explicit change made to $scriptProperties, is A. However both return B.

It also goes the other way, though this type of code would be less common:

<?php
$scriptProperties['my_prop'] = 'B';
return $my_prop;

Related issue(s)/PR(s)

https://community.modx.com/t/spform-how-to-change-language/4917/15
#15578

[rthrash]

This pull request has been mentioned on MODX Community. There might be relevant details there:

https://community.modx.com/t/spform-how-to-change-language/4917/19

[BobRay]

IMO, this should be applied. Passing $scriptProperties by reference is asking for trouble, since many plugins and snippets use variable names that are in the $sccriptProperties array. I suspect that it also introduces opportunities for malicious code. since any variable in the $scriptProperties array could be modified.

[opengeek]

@BobRay — It is already applied and live in the RC2 download.

[BobRay]

Thanks. I should have checked.