N°8681 - PHP 8.1: Fix deprecated notice for null value passed to preg_match_all()

[Molkobain]

Base information

Question	Answer
Related to a SourceForge thread / Another PR / Combodo ticket?	N°8681
Type of change?	Bug fix

Symptom (bug)

Deprecated Passing null to parameter #2 ($subject) of type string is deprecated in core/attributedef.class.inc.php on line 4469
Deprecated Passing null to parameter #2 ($subject) of type string is deprecated in core/inlineimage.cIass.inc.php on line 291

Reproduction procedure (bug)

1. On iTop 3.2.2
2. With PHP 8.1.0
3. With a particular customization ??

I could not find how to reproduce locally what we witnessed on the customer's instance...

Cause (bug)

Shallow cause:
In AttributeText::GetAsHTML(), $sValue seems to be null in some cases, which when passed to AttributeText::RenderWikiHtml() and InlineImage::FixUrls() will be passed to preg_match_all() in the $subject parameter that as of PHP 8.1 only supports string values.

Root cause:
How we happen to pass null in AttributeText::GetAsHTML() remains a mystery for now.

Proposed solution (bug and enhancement)

Even though we can't find where the null comes from, we can harden the AttributeText::RenderWikiHtml() and InlineImage::FixUrls() methods so they convert null values to string. Minimizing the risk of regression while fixing the issue.

During the merge into 3.3 branch, I suggest to also change the AttributeText::RenderWikiHtml() and InlineImage::FixUrls() methods prototype to type the relevant parameter to string|null.

Checklist before requesting a review

• I have performed a self-review of my code
• I have tested all changes I made on an iTop instance
• I have added a unit test, otherwise I have explained why I couldn't
• Is the PR clear and detailed enough so anyone can understand digging in the code?

Checklist of things to do before PR is ready to merge

[Copilot]

Pull request overview

Fixes PHP 8.1 deprecation notices caused by passing null as the $subject argument to preg_match_all() by hardening wiki/HTML rendering paths to coerce null inputs to empty strings.

Changes:

• Coerce null to '' in AttributeText::RenderWikiHtml() before running regex processing.
• Coerce null to '' in InlineImage::FixUrls() before parsing/replacing <img ... data-img-id="..."> tags.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 3 comments.

File	Description
core/inlineimage.class.inc.php	Hardens InlineImage::FixUrls() against null input before calling preg_match_all().
core/attributedef.class.inc.php	Hardens AttributeText::RenderWikiHtml() against null input before calling preg_match_all().

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