deprecation warning on wikimedia/less.php/lib/Less/Functions.php:1022

[spoetnik]

I have updated a Processwire module to use the latest version of wikimedia Less. I get a deprecation warning on wikimedia/less.php/lib/Less/Functions.php:1022

Deprecated: file_exists(): Passing null to parameter #1 ($filename) of type string is deprecated in .../modules/Less/wikimedia/less.php/lib/Less/Functions.php:1022

I don't think this has something todo with the implementation of the less.php library in the module.

php_version: "8.2" webserver_type: apache-fpm

[Krinkle]

@spoetnik Can you share a minimal input that triggers the warning? For example, a 5-10 line .less file that one can pass to less.php/bin/lessc.

Does it function correctly / Do you get the output you expect? (Besides this warning.)

Are there other warnings or errors caused by the same input?

[spoetnik]

I find it hard to debug this, but if I remove these lines from my Less-file, the warnings are gone:

@internal-accordion-icon-close-image: "uikit-themes/master-design-escapes/images/accordion-close.svg";
@internal-accordion-icon-open-image: "uikit-themes/master-design-escapes /images/accordion-open.svg";
@internal-divider-icon-image: "uikit-themes/master-design-escapes/images/divider-icon.svg";

I get 18 warnings for these 3 lines.