[REF] Fix handling of NULL values in count_characters smarty modifier…

[seamuslee001]

… by creating a CiviCRM specific one that handles them

Overview

This fixes a PHP8.1 issue whetre passing NULL to the 2nd parameter to preg_match_all is deprecated

Before

Deprecation error on php8.1

Deprecated: preg_match_all(): Passing null to parameter #2 ($subject) of type string is deprecated in /home/jenkins/bknix-edge/build/build-2/web/sites/all/modules/civicrm/packages/Smarty/plugins/modifier.count_characters.php on line 27

Call Stack:
    0.0004     427320   1. {main}() /home/jenkins/bknix-edge/build/build-2/web/sites/all/modules/civicrm/xml/GenCode.php:0
    0.0048    1094120   2. CRM_Core_CodeGen_Main->main() /home/jenkins/bknix-edge/build/build-2/web/sites/all/modules/civicrm/xml/GenCode.php:58
    0.2600    9389072   3. CRM_Core_CodeGen_Schema->run() /home/jenkins/bknix-edge/build/build-2/web/sites/all/modules/civicrm/CRM/Core/CodeGen/Main.php:115

After

no deprecation error

ping @eileenmcnaughton @demeritcowboy

[civibot]

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[eileenmcnaughton]

@seamuslee001

[totten]

@seamuslee001 I added a commit to fixup the code-style issue.

I couldn't figure out how to reproduce a warning from the snippet in schema.tpl. Tried GENCODE_FORCE=1 and tried deleting/regenerating various files (sql/civicrm.mysql and most DAOs). FWIW, I'm running php 8.1.2.

Did you originally observe the error in GenCode -- or was that just an incidental bit that up during search/replace? (I think it's fine to change that one proactively -- just not clear but what to test.)

[demeritcowboy]

I see the schema one is doing something - before the patch if I do

cd xml
php GenCode.php

Then I get a bunch of errors about line 27: PHP Deprecated: preg_match_all(): Passing null to parameter #2 ($subject) of type string is deprecated in ...\packages\Smarty\plugins\modifier.count_characters.php on line 27

Am also using php 8.1.2.

If I only apply the schema part of the patch I don't get those, so it must be from there.

[demeritcowboy]

I think this is mergeable as-is just noting some possible improvements:

• The check for null here could come before potentially passing to strlen()
• While copied from the original function, strlen isn't multibyte-friendly. In the places where it's used currently it doesn't make too much difference.
• The use in schema.xml is really checking for something like if $field.default !== null && $field.default !== '' (i.e. '0' is allowed but not null or blank). So could avoid the function.

[demeritcowboy]

Going to merge but I'm going to put up a followup to move the check for null to ahead of sending it to strlen.