register_legacy_post_comments_block() │ WP 6.1.0

Ensures backwards compatibility for any users running the Gutenberg plugin who have used Post Comments before it was merged into Comments Query Loop.

The same approach was followed when core/query-loop was renamed to core/post-template.

Hooks from the function

Returns

null. Nothing (null).

Usage

register_legacy_post_comments_block();

Notes

Changelog

Since 6.1.0 Introduced.

register_legacy_post_comments_block() code WP 6.9

wp-includes/blocks/comments.php 
function register_legacy_post_comments_block() {
	$registry = WP_Block_Type_Registry::get_instance();

	/*
	 * Remove the old `post-comments` block if it was already registered, as it
	 * is about to be replaced by the type defined below.
	 */
	if ( $registry->is_registered( 'core/post-comments' ) ) {
		unregister_block_type( 'core/post-comments' );
	}

	// Recreate the legacy block metadata.
	$metadata = array(
		'name'              => 'core/post-comments',
		'category'          => 'theme',
		'attributes'        => array(
			'textAlign' => array(
				'type' => 'string',
			),
		),
		'uses_context'      => array(
			'postId',
			'postType',
		),
		'supports'          => array(
			'html'       => false,
			'align'      => array( 'wide', 'full' ),
			'typography' => array(
				'fontSize'                      => true,
				'lineHeight'                    => true,
				'__experimentalFontStyle'       => true,
				'__experimentalFontWeight'      => true,
				'__experimentalLetterSpacing'   => true,
				'__experimentalTextTransform'   => true,
				'__experimentalDefaultControls' => array(
					'fontSize' => true,
				),
			),
			'color'      => array(
				'gradients'                     => true,
				'link'                          => true,
				'__experimentalDefaultControls' => array(
					'background' => true,
					'text'       => true,
				),
			),
			'inserter'   => false,
		),
		'style'             => array(
			'wp-block-post-comments',
			'wp-block-buttons',
			'wp-block-button',
		),
		'render_callback'   => 'render_block_core_comments',
		'skip_inner_blocks' => true,
	);

	/*
	 * Filters the metadata object, the same way it's done inside
	 * `register_block_type_from_metadata()`. This applies some default filters,
	 * like `_wp_multiple_block_styles`, which is required in this case because
	 * the block has multiple styles.
	 */
	/** This filter is documented in wp-includes/blocks.php */
	$metadata = apply_filters( 'block_type_metadata', $metadata );

	register_block_type( 'core/post-comments', $metadata );
}