RSS block: check for description field before rendering excerpt

[ramonjd]

What? and How?

In the RSS block render code, check for author and description (excerpt) before passing to strip_tags and html_entity_decode.

Why?

Some RSS feeds don't have description or author fields.

And PHP complains:

Deprecated: html_entity_decode(): Passing null to parameter #1 ($string) of type string is deprecated 

Deprecated: strip_tags(): Passing null to parameter #1 ($string) of type string is deprecated

Noticed while testing #66419

Testing Instructions

1. Insert an RSS block
2. Insert an RSS feed that doesn't have description fields, e.g., http://rss.news.yahoo.com/rss/world
3. Enable "Display excerpt" and "Display author" in the block's settings.
4. Save and check that PHP deprecation warning doesn't appear in the editor or frontend.
5. Insert an RSS feed that doesn't have author fields: https://feeds.simplecast.com/qm_9xx0g
6. Save and check that PHP deprecation warning doesn't appear in the editor or frontend.

[github-actions]

The following accounts have interacted with this PR and/or linked issues. I will continue to update these lists as activity occurs. You can also manually ask me to refresh this list by adding the props-bot label.

If you're merging code through a pull request on GitHub, copy and paste the following into the bottom of the merge commit message.

Co-authored-by: ramonjd <[email protected]>
Co-authored-by: aaronrobertshaw <[email protected]>

To understand the WordPress project's expectations around crediting contributors, please review the Contributor Attribution page in the Core Handbook.

[github-actions]

Flaky tests detected in 03bcd86.
Some tests passed with failed attempts. The failures may not be related to this commit but are still reported for visibility. See the documentation for more information.

🔍 Workflow run URL: https://github.com/WordPress/gutenberg/actions/runs/11830605502
📝 Reported issues:

• [Flaky Test] Navigates the items list via UP/DOWN arrow keys #64334 in /test/e2e/specs/site-editor/dataviews-list-layout-keyboard.spec.js

[aaronrobertshaw]

LGTM 👍

Thanks for the quick fix!

✅ RSS feeds without descriptions no longer throw warnings
✅ RSS feeds with descriptions continue to display appropriately
❓ Is it worth also fixing the "author" use case as well?

Using the RSS feeds supplied in the test instructions, I saw similar PHP warnings when choosing to display the author while it was missing:

strip_tags(): Passing null to parameter #1 ($string) of type string is deprecated

I think we might need to guard against that here.

Would you like to roll that fix into this PR or do it separately?

In case you'd prefer the latter, I'll approve this one now.

[ramonjd]

Is it worth also fixing the "author" use case as well?

Oh yeah, why not?! Thanks for testing. I didn't come across that but definitely worth fixing here.

[aaronrobertshaw]

Thanks for fixing up the author side of things as well. Appreciate it 👍

I've taken this for another spin and no longer receive the warnings for missing authors or description in the RSS feeds.