Disable contact forms on past WordCamp sites

[dd32]

Summary

• Replaces Jetpack contact form HTML with a message on past WordCamp sites to reduce spam to organizers
• Forms are disabled when either:
  1. A newer event site exists for the same city (using existing get_latest_home_url() logic), OR
  2. The event ended more than 18 months ago (covers cities that stopped hosting events)
• The replacement message directs visitors to the latest edition (if one exists) and always includes a link to report Code of Conduct concerns to the WordPress Incident Response Team at reports@wordpress.org
• Uses the jetpack_contact_form_html filter as suggested by @jeherve in the issue discussion
• Added to latest-site-hints.php as suggested by @dd32

Implementation details

• Reuses the existing get_latest_home_url() function and get_wordcamp_post() end date logic
• Events still in progress (within 1 day of end date) keep their forms active
• The 18-month grace period ensures forms stay active for slightly longer than a year after the event, giving time for a new edition to be scheduled

Test plan

• Visit a past WordCamp site that has a newer edition — verify contact form is replaced with message linking to the new site
• Visit the most recent WordCamp site for a city — verify contact form still works
• Verify the Code of Conduct reporting link appears in the replacement message
• Visit a site whose event ended less than 18 months ago with no newer site — verify form still works
• Visit a site whose event ended more than 18 months ago with no newer site — verify form is replaced

Fixes #1468

🤖 Generated with Claude Code

[Copilot]

Pull request overview

This PR disables Jetpack contact forms on past WordCamp sites (to reduce spam to past organizers) by replacing the rendered form HTML with an informational message, based on whether a newer edition exists for the same city and/or the event is sufficiently old. It also adds test coverage around the new behavior and introduces transient caching for the “latest site” lookup.

Changes:

• Add a jetpack_contact_form_html filter that replaces contact form HTML with a guidance + Code of Conduct reporting message when the site is considered “past.”
• Add transient caching around latest-site lookups by splitting the logic into get_latest_home_url() (cached) and query_latest_home_url() (query).
• Add a new PHPUnit test file covering the contact-form disabling behavior.

Reviewed changes

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

File	Description
public_html/wp-content/mu-plugins/latest-site-hints.php	Adds the Jetpack form-disabling filter and introduces cached latest-site lookup via a wrapper + renamed query function.
public_html/wp-content/mu-plugins/tests/test-disable-contact-form.php	Adds PHPUnit coverage for the form-disabling behavior across several site/event scenarios.

Comments suppressed due to low confidence (1)

public_html/wp-content/mu-plugins/latest-site-hints.php:272

• get_wordcamp_post() can return false; query_latest_home_url() currently dereferences $wordcamp->meta unconditionally, which will fatally error if a site isn’t linked to a WordCamp post. Returning false is consistent with the function’s contract.

	$wordcamp = get_wordcamp_post();
	$end_date = absint( $wordcamp->meta['End Date (YYYY-mm-dd)'][0] ?? 0 );