fix: resolve PHP 8.1+ TypeError that hides Save button on Domain Mapping settings (#823)

[superdav42]

Summary

Fixes the "Domain mapping no way to save" bug (GH#823).

Root cause: DNS_Record_Manager::add_dns_settings() registered dns_record_types_allowed as a multiselect field with options defined as plain strings ('A' => 'A (IPv4 Address)'). The field-multiselect.php template accessed $option['title'] on each option. On PHP 8.1+, accessing a string value with a non-integer string key throws TypeError: Cannot access offset of type string on string, which interrupted form rendering before the Save Settings button could be output.

Changes:

• inc/managers/class-dns-record-manager.php: Convert dns_record_types_allowed options from plain strings to the ['title' => '...'] array format expected by the multiselect template.
• views/admin-pages/fields/field-multiselect.php: Harden the template to support both string and array option formats for backward compatibility with any existing multiselect fields that use plain strings.

Testing

# Verify no TypeError during domain-mapping form rendering
wp --path=../wordpress --user=admin eval '
$sections = WP_Ultimo()->settings->get_sections();
$section = $sections["domain-mapping"];
$fields = array_filter($section["fields"] ?? [], fn($item) => current_user_can($item["capability"]));
uasort($fields, "wu_sort_by_order");
$fields["save"] = ["type" => "submit", "title" => "Save Settings"];
ob_start();
$form = new \WP_Ultimo\UI\Form("domain-mapping", $fields, ["views" => "admin-pages/fields", "html_attr" => ["data-state" => "{}"]]);
$form->render();
$html = ob_get_clean();
echo (strpos($html, "Save Settings") !== false ? "PASS: Save button present" : "FAIL: Save button missing") . "\n";
'

Visit Settings > Domain Mapping in network admin — the "Save Settings" button now renders correctly on PHP 8.1+.

Resolves #823

Summary by CodeRabbit

• Refactor
  • Updated DNS record type options data structure for improved consistency.
  • Enhanced multiselect field rendering to support flexible option formats with backward compatibility.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: d1923a6a-e85d-4bbb-a86b-2d800e22631a

📥 Commits

Reviewing files that changed from the base of the PR and between b2b64c4 and c3f9cf3.

📒 Files selected for processing (2)

• inc/managers/class-dns-record-manager.php
• views/admin-pages/fields/field-multiselect.php

---

📝 Walkthrough

Walkthrough

The DNS record types option structure was refactored from direct string values to associative arrays with a title key. The multiselect field template was updated to support both option formats for backward compatibility during rendering.

Changes

Cohort / File(s)	Summary
DNS Record Options Structure inc/managers/class-dns-record-manager.php	Changed DNS record type keys (A, AAAA, CNAME, MX, TXT) option values from direct translated strings to associative arrays containing a title key with the translated string.
Multiselect Field Rendering views/admin-pages/fields/field-multiselect.php	Updated option rendering to detect and handle both string and array option formats. Added null-coalescing logic to derive option_title and option_desc with appropriate defaults based on option type.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~10 minutes

Poem

🐰 DNS records neatly arranged,
In structured arrays, beautifully changed,
Old strings and new arrays both sing,
The multiselect field handles everything! 🎉

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly and specifically describes the main bug fix: resolving a PHP 8.1+ TypeError that prevents the Save button from displaying on Domain Mapping settings.
Linked Issues check	✅ Passed	The PR directly addresses issue #823 by fixing the TypeError in the Domain Mapping form rendering, restoring the ability to save Domain Mapping settings as required.
Out of Scope Changes check	✅ Passed	All changes are directly scoped to fixing the Domain Mapping form rendering issue: DNS option format conversion and multiselect template backward compatibility.
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch feature/auto-20260413-124559

---

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[github-actions]

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[github-actions]

Performance Test Results

Performance test results for c59a9ae are in 🛎️!

Note: the numbers in parentheses show the difference to the previous (baseline) test run. Differences below 2% or 0.5 in absolute values are not shown.

URL: /

Run	DB Queries	Memory	Before Template	Template	WP Total	LCP	TTFB	LCP - TTFB
0	41	37.80 MB	863.00 ms (+29.00 ms / +3% )	151.00 ms (-5.50 ms / -4% )	1049.00 ms	2040.00 ms	1943.15 ms	86.10 ms (-4.25 ms / -5% )
1	56	49.02 MB	931.00 ms	144.50 ms	1074.50 ms	2046.00 ms	1968.75 ms	80.45 ms