[noruzzamans]

Description

Replaces verbose ! isset() guard blocks that assign default values with the null coalescing assignment operator (??=) in src/wp-includes/comment.php:

// 1. Pagination and threading defaults in get_comment_pages_count()
$per_page ??= (int) get_query_var( 'comments_per_page' );
$threaded ??= get_option( 'thread_comments' );

// 2. Author IP and user agent defaults in wp_new_comment()
$commentdata['comment_author_IP'] ??= $_SERVER['REMOTE_ADDR'];
$commentdata['comment_agent']     ??= $_SERVER['HTTP_USER_AGENT'] ?? '';

Scope

This covers get_comment_pages_count() and wp_new_comment() in src/wp-includes/comment.php completely. All changed guards are simple default assignments to tested variables/keys, reducing boilerplate while keeping the function logic identical. 4 guard blocks replaced, 13 lines removed for 4 added (-9 net lines).

Why this is safe

• ??= requires PHP 7.4, which is the minimum supported version for WordPress Core.
• ??= and ! isset() test the exact same condition, so default values are applied in identical scenarios.
• Pre-existing inline coalescing ($_SERVER['HTTP_USER_AGENT'] ?? '') is naturally complemented.
• Assignment evaluation order is fully preserved.
• Purely internal code simplification with no behavioral or architectural changes.

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Trac ticket: https://core.trac.wordpress.org/ticket/65823

[github-actions]

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[Copilot]

🟢 Approval recommended

No active review issues are reported for the comment-default assignment simplification.

No open issues 🎉

What changed in this PR

Modernizes default assignments in WordPress Core’s comment handling by replacing four ! isset() guard blocks with ??=, preserving existing behavior.

Changes:

• Simplifies pagination and threading defaults in get_comment_pages_count().
• Simplifies author IP and user agent defaults in wp_new_comment().

File	Description
src/​wp-includes/​comment.php	Replaces four default-assignment guards with null coalescing assignments.

_{Review effort: Balanced}

[github-actions]

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Props noruzzaman.

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