编辑文件

编辑文件：class-wc-comments.php

<?php
/**
 * Comments
 *
 * Handle comments (reviews and order notes).
 *
 * @package WooCommerce\Classes\Products
 * @version 2.3.0
 */

use Automattic\WooCommerce\Internal\Admin\ProductReviews\ReviewsUtil;

defined( 'ABSPATH' ) || exit;

/**
 * Comments class.
 */
class WC_Comments {

/**
	 * The cache group to use for comment counts.
	 *
	 * @var string
	 */
	private const COMMENT_COUNT_CACHE_GROUP = 'wc_comment_counts';

/**
	 * The cache key to use for pending product reviews counts.
	 *
	 * @var string
	 */
	private const PRODUCT_REVIEWS_PENDING_COUNT_CACHE_KEY = 'woocommerce_product_reviews_pending_count';

/**
	 * Hook in methods.
	 */
	public static function init() {
		// Rating posts.
		add_filter( 'comments_open', array( __CLASS__, 'comments_open' ), 10, 2 );
		add_filter( 'preprocess_comment', array( __CLASS__, 'check_comment_rating' ), 0 );
		add_action( 'comment_post', array( __CLASS__, 'add_comment_rating' ), 1 );
		add_action( 'comment_moderation_recipients', array( __CLASS__, 'comment_moderation_recipients' ), 10, 2 );

// Clear transients.
		add_action( 'wp_update_comment_count', array( __CLASS__, 'clear_transients' ) );

// Secure order notes.
		add_filter( 'comments_clauses', array( __CLASS__, 'exclude_order_comments' ) );
		add_filter( 'comment_feed_where', array( __CLASS__, 'exclude_order_comments_from_feed_where' ) );
		add_filter( 'akismet_excluded_comment_types', array( __CLASS__, 'akismet_excluded_comment_types' ) );

// Secure webhook comments.
		add_filter( 'comments_clauses', array( __CLASS__, 'exclude_webhook_comments' ), 10, 1 );
		add_filter( 'comment_feed_where', array( __CLASS__, 'exclude_webhook_comments_from_feed_where' ) );

// Secure potential remaining Action Logs.
		add_filter( 'comments_clauses', array( __CLASS__, 'exclude_action_log_comments' ), 10, 2 );
		add_filter( 'comment_feed_where', array( __CLASS__, 'exclude_action_log_comments_from_feed_where' ) );

// Exclude product reviews from general comments.
		add_filter( 'comments_clauses', array( ReviewsUtil::class, 'comments_clauses_without_product_reviews' ), 10, 2 );

// Modifies the moderation URLs in the email notifications for product reviews.
		add_filter( 'comment_moderation_text', array( ReviewsUtil::class, 'modify_product_review_moderation_urls' ), 10, 2 );

// Count comments.
		add_filter( 'wp_count_comments', array( __CLASS__, 'wp_count_comments' ), 10, 2 );

// Actualize comments count cache whenever there is a new comment or a comment status changes.
		add_action( 'wp_insert_comment', array( __CLASS__, 'increment_comments_count_cache_on_wp_insert_comment' ), 10, 2 );
		add_action( 'transition_comment_status', array( __CLASS__, 'update_comments_count_cache_on_comment_status_change' ), 10, 3 );

// Count product reviews that pending moderation.
		add_action( 'wp_insert_comment', array( __CLASS__, 'maybe_bump_products_reviews_pending_moderation_counter' ), 10, 2 );
		add_action( 'transition_comment_status', array( __CLASS__, 'maybe_adjust_products_reviews_pending_moderation_counter' ), 10, 3 );

// Support avatars for `review` comment type.
		add_filter( 'get_avatar_comment_types', array( __CLASS__, 'add_avatar_for_review_comment_type' ) );

// Add Product Reviews filter for `review` comment type.
		add_filter( 'admin_comment_types_dropdown', array( __CLASS__, 'add_review_comment_filter' ) );

// Review of verified purchase.
		add_action( 'comment_post', array( __CLASS__, 'add_comment_purchase_verification' ) );

// Set comment type.
		add_action( 'preprocess_comment', array( __CLASS__, 'update_comment_type' ), 1 );

// Validate product reviews if requires verified owners.
		add_action( 'pre_comment_on_post', array( __CLASS__, 'validate_product_review_verified_owners' ) );
	}

/**
	 * See if comments are open.
	 *
	 * @since  3.1.0
	 * @param  bool $open    Whether the current post is open for comments.
	 * @param  int  $post_id Post ID.
	 * @return bool
	 */
	public static function comments_open( $open, $post_id ) {
		if ( 'product' === get_post_type( $post_id ) && ! post_type_supports( 'product', 'comments' ) ) {
			$open = false;
		}
		return $open;
	}

/**
	 * Exclude order comments from queries and RSS.
	 *
	 * This code should exclude shop_order comments from queries. Some queries (like the recent comments widget on the dashboard) are hardcoded.
	 * and are not filtered, however, the code current_user_can( 'read_post', $comment->comment_post_ID ) should keep them safe since only admin and.
	 * shop managers can view orders anyway.
	 *
	 * The frontend view order pages get around this filter by using remove_filter('comments_clauses', array( 'WC_Comments' ,'exclude_order_comments'), 10, 1 );
	 *
	 * @param  array $clauses A compacted array of comment query clauses.
	 * @return array
	 */
	public static function exclude_order_comments( $clauses ) {
		$clauses['where'] .= ( trim( $clauses['where'] ) ? ' AND ' : '' ) . " comment_type != 'order_note' ";
		return $clauses;
	}

/**
	 * Exclude order comments from Akismet comments counting SQL queries for better performance.
	 *
	 * @since 10.6.0
	 *
	 * @param string[] $comment_types Excluded comments types.
	 * @return string[]
	 */
	public static function akismet_excluded_comment_types( $comment_types ): array {
		$comment_types[] = 'order_note';
		return $comment_types;
	}

/**
	 * Exclude order comments from feed.
	 *
	 * @deprecated 3.1
	 * @param mixed $join Deprecated.
	 */
	public static function exclude_order_comments_from_feed_join( $join ) {
		wc_deprecated_function( 'WC_Comments::exclude_order_comments_from_feed_join', '3.1' );
	}

/**
	 * Exclude order comments from queries and RSS.
	 *
	 * @param  string $where The WHERE clause of the query.
	 * @return string
	 */
	public static function exclude_order_comments_from_feed_where( $where ) {
		return $where . ( trim( $where ) ? ' AND ' : '' ) . " comment_type != 'order_note' ";
	}

/**
	 * Exclude webhook comments from queries and RSS.
	 *
	 * @since  2.2
	 * @param  array $clauses A compacted array of comment query clauses.
	 * @return array
	 */
	public static function exclude_webhook_comments( $clauses ) {
		$clauses['where'] .= ( trim( $clauses['where'] ) ? ' AND ' : '' ) . " comment_type != 'webhook_delivery' ";
		return $clauses;
	}

/**
	 * Exclude webhooks comments from feed.
	 *
	 * @deprecated 3.1
	 * @param mixed $join Deprecated.
	 */
	public static function exclude_webhook_comments_from_feed_join( $join ) {
		wc_deprecated_function( 'WC_Comments::exclude_webhook_comments_from_feed_join', '3.1' );
	}

/**
	 * Exclude webhook comments from queries and RSS.
	 *
	 * @since  2.1
	 * @param  string $where The WHERE clause of the query.
	 * @return string
	 */
	public static function exclude_webhook_comments_from_feed_where( $where ) {
		return $where . ( trim( $where ) ? ' AND ' : '' ) . " comment_type != 'webhook_delivery' ";
	}

/**
	 * Exclude action_log comments from queries and RSS.
	 *
	 * @since  9.9
	 * @param  string $where The WHERE clause of the query.
	 * @return string
	 */
	public static function exclude_action_log_comments_from_feed_where( $where ) {
		return $where . ( trim( $where ) ? ' AND ' : '' ) . " comment_type != 'action_log' ";
	}

/**
	 * Exclude action_log comments from queries.
	 *
	 * @param array            $clauses       A compacted array of comment query clauses.
	 * @param WP_Comment_Query $comment_query The WP_Comment_Query being filtered.
	 *
	 * @return array
	 * @since  9.9
	 */
	public static function exclude_action_log_comments( $clauses, $comment_query ) {
		if ( 'action_log' !== $comment_query->query_vars['type'] ) {
			$clauses['where'] .= ( trim( $clauses['where'] ) ? ' AND ' : '' ) . " comment_type != 'action_log' ";
		}

return $clauses;
	}

/**
	 * Validate the comment ratings.
	 *
	 * @param  array $comment_data Comment data.
	 * @return array
	 */
	public static function check_comment_rating( $comment_data ) {
		// If posting a comment (not trackback etc) and not logged in.
		if ( ! is_admin() && isset( $_POST['comment_post_ID'], $_POST['rating'], $comment_data['comment_type'] ) && 'product' === get_post_type( absint( $_POST['comment_post_ID'] ) ) && empty( $_POST['rating'] ) && self::is_default_comment_type( $comment_data['comment_type'] ) && wc_review_ratings_enabled() && wc_review_ratings_required() ) { // WPCS: input var ok, CSRF ok.
			wp_die( esc_html__( 'Please rate the product.', 'woocommerce' ) );
			exit;
		}
		return $comment_data;
	}

/**
	 * Rating field for comments.
	 *
	 * @param int $comment_id Comment ID.
	 */
	public static function add_comment_rating( $comment_id ) {
		if ( isset( $_POST['rating'], $_POST['comment_post_ID'] ) && 'product' === get_post_type( absint( $_POST['comment_post_ID'] ) ) ) { // WPCS: input var ok, CSRF ok.
			if ( ! $_POST['rating'] || $_POST['rating'] > 5 || $_POST['rating'] < 0 ) { // WPCS: input var ok, CSRF ok, sanitization ok.
				return;
			}
			add_comment_meta( $comment_id, 'rating', intval( $_POST['rating'] ), true ); // WPCS: input var ok, CSRF ok.

$post_id = isset( $_POST['comment_post_ID'] ) ? absint( $_POST['comment_post_ID'] ) : 0; // WPCS: input var ok, CSRF ok.
			if ( $post_id ) {
				self::clear_transients( $post_id );
			}
		}
	}

/**
	 * Modify recipient of review email.
	 *
	 * @param array $emails     Emails.
	 * @param int   $comment_id Comment ID.
	 * @return array
	 */
	public static function comment_moderation_recipients( $emails, $comment_id ) {
		$comment = get_comment( $comment_id );

if ( $comment && 'product' === get_post_type( $comment->comment_post_ID ) ) {
			$emails = array( get_option( 'admin_email' ) );
		}

return $emails;
	}

/**
	 * Ensure product average rating and review count is kept up to date.
	 *
	 * @param int $post_id Post ID.
	 */
	public static function clear_transients( $post_id ) {
		$post_id = absint( $post_id );
		if ( 0 === $post_id || 'product' !== get_post_type( $post_id ) ) {
			return;
		}

$product = wc_get_product( $post_id );
		if ( $product instanceof WC_Product ) {
			$product->set_rating_counts( self::get_rating_counts_for_product( $product ) );
			$product->set_average_rating( self::get_average_rating_for_product( $product ) );
			$product->set_review_count( self::get_review_count_for_product( $product ) );
			$product->save();
		}
	}

/**
	 * Callback for 'wp_insert_comment' to delete the comment count cache if the comment is included in the count.
	 *
	 * @param int        $comment_id The comment ID.
	 * @param WP_Comment $comment    Comment object.
	 *
	 * @return void
	 */
	public static function increment_comments_count_cache_on_wp_insert_comment( $comment_id, $comment ) {
		if ( ! self::is_comment_excluded_from_wp_comment_counts( $comment ) ) {
			$comment_status = wp_get_comment_status( $comment );
			if ( false !== $comment_status ) {
				wp_cache_incr( 'wc_count_comments_' . $comment_status, 1, self::COMMENT_COUNT_CACHE_GROUP );
			}
		}
	}

/**
	 * Callback for 'comment_status_change' to delete the comment count cache if the comment is included in the count.
	 *
	 * @param int|string $new_status The new comment status.
	 * @param int|string $old_status The old comment status.
	 * @param WP_Comment $comment    Comment object.
	 *
	 * @return void
	 */
	public static function update_comments_count_cache_on_comment_status_change( $new_status, $old_status, $comment ) {
		if ( ! self::is_comment_excluded_from_wp_comment_counts( $comment ) ) {
			wp_cache_incr( 'wc_count_comments_' . $new_status, 1, self::COMMENT_COUNT_CACHE_GROUP );
			wp_cache_decr( 'wc_count_comments_' . $old_status, 1, self::COMMENT_COUNT_CACHE_GROUP );
		}
	}

/**
	 * Determines whether the given comment should be included in the core WP comment counts that are displayed in the
	 * WordPress admin.
	 *
	 * @param WP_Comment $comment Comment object.
	 *
	 * @return bool
	 */
	private static function is_comment_excluded_from_wp_comment_counts( $comment ) {
		return in_array( $comment->comment_type, array( 'action_log', 'order_note', 'webhook_delivery' ), true )
			|| get_post_type( $comment->comment_post_ID ) === 'product';
	}

/**
	 * Delete comments count cache whenever there is
	 * new comment or the status of a comment changes. Cache
	 * will be regenerated next time WC_Comments::wp_count_comments()
	 * is called.
	 */
	public static function delete_comments_count_cache() {
		$comment_status_keys = array(
			'wc_count_comments_approved',
			'wc_count_comments_unapproved',
			'wc_count_comments_spam',
			'wc_count_comments_trash',
			'wc_count_comments_post-trashed',
		);
		wp_cache_delete_multiple( $comment_status_keys, self::COMMENT_COUNT_CACHE_GROUP );
	}

/**
	 * Fetches (and populates if needed) the counter.
	 *
	 * @return int
	 */
	public static function get_products_reviews_pending_moderation_counter(): int {
		$count = wp_cache_get( self::PRODUCT_REVIEWS_PENDING_COUNT_CACHE_KEY, self::COMMENT_COUNT_CACHE_GROUP );
		if ( false === $count ) {
			$count = (int) get_comments(
				array(
					'type__in'  => array( 'review', 'comment' ),
					'status'    => '0',
					'post_type' => 'product',
					'count'     => true,
				)
			);
			wp_cache_set( self::PRODUCT_REVIEWS_PENDING_COUNT_CACHE_KEY, $count, self::COMMENT_COUNT_CACHE_GROUP, DAY_IN_SECONDS );
		}

return $count;
	}

/**
	 * Handles `wp_insert_comment` hook processing and actualizes the counter.
	 *
	 * @param int         $comment_id Comment ID.
	 * @param \WP_Comment $comment    Comment object.
	 * @return void
	 */
	public static function maybe_bump_products_reviews_pending_moderation_counter( $comment_id, $comment ): void {
		$needs_bump = '0' === $comment->comment_approved;
		if ( $needs_bump && in_array( $comment->comment_type, array( 'review', 'comment', '' ), true ) ) {
			$is_product = 'product' === get_post_type( $comment->comment_post_ID );
			if ( $is_product ) {
				wp_cache_incr( self::PRODUCT_REVIEWS_PENDING_COUNT_CACHE_KEY, 1, self::COMMENT_COUNT_CACHE_GROUP );
			}
		}
	}

/**
	 * Handles `transition_comment_status` hook processing and actualizes the counter.
	 *
	 * @param int|string  $new_status New status.
	 * @param int|string  $old_status Old status.
	 * @param \WP_Comment $comment    Comment object.
	 * @return void
	 */
	public static function maybe_adjust_products_reviews_pending_moderation_counter( $new_status, $old_status, $comment ): void {
		$needs_adjustments = 'unapproved' === $new_status || 'unapproved' === $old_status;
		if ( $needs_adjustments && in_array( $comment->comment_type, array( 'review', 'comment', '' ), true ) ) {
			$is_product = 'product' === get_post_type( $comment->comment_post_ID );
			if ( $is_product ) {
				if ( '0' === $comment->comment_approved ) {
					wp_cache_incr( self::PRODUCT_REVIEWS_PENDING_COUNT_CACHE_KEY, 1, self::COMMENT_COUNT_CACHE_GROUP );
				} else {
					wp_cache_decr( self::PRODUCT_REVIEWS_PENDING_COUNT_CACHE_KEY, 1, self::COMMENT_COUNT_CACHE_GROUP );
				}
			}
		}
	}

/**
	 * Remove order notes, webhook delivery logs, and product reviews from wp_count_comments().
	 *
	 * @param array|object $stats   Comment stats.
	 * @param int          $post_id Post ID.
	 *
	 * @return object
	 * @since  2.2
	 */
	public static function wp_count_comments( $stats, $post_id ) {
		if ( 0 !== $post_id || ! empty( $stats ) ) {
			// If $stats isn't empty, another plugin may have already made changes to the values that we can't account for, so we don't attempt to modify it.
			return $stats;
		}

$comment_counts = array();

// WordPress is inconsistent in the names it uses for approved/unapproved comment statuses, so we need to remap the names.
		$stat_key_to_comment_query_status_mapping = array(
			'approved'     => 'approve',
			'moderated'    => 'hold',
			'spam'         => 'spam',
			'trash'        => 'trash',
			'post-trashed' => 'post-trashed',
		);

$comment_query_status_to_comment_status_mapping = array(
			'approve'      => 'approved',
			'hold'         => 'unapproved',
			'spam'         => 'spam',
			'trash'        => 'trash',
			'post-trashed' => 'post-trashed',
		);

$args = array(
			'count'                     => true,
			'update_comment_meta_cache' => false,
			'orderby'                   => 'none',
		);

foreach ( $stat_key_to_comment_query_status_mapping as $stat_key => $query_status ) {
			// For simplicity, the cache key is by the comment status returned by wp_get_comment_status() and used by wp_transition_comment_status().
			$cache_key = 'wc_count_comments_' . $comment_query_status_to_comment_status_mapping[ $query_status ];
			$count     = wp_cache_get( $cache_key, self::COMMENT_COUNT_CACHE_GROUP );
			if ( false === $count ) {
				$count = (int) get_comments( array_merge( $args, array( 'status' => $query_status ) ) );
				wp_cache_set( $cache_key, $count, self::COMMENT_COUNT_CACHE_GROUP, 3 * DAY_IN_SECONDS );
			}
			$comment_counts[ $stat_key ] = (int) $count;
		}

$comment_counts['all']            = $comment_counts['approved'] + $comment_counts['moderated'];
		$comment_counts['total_comments'] = $comment_counts['all'] + $comment_counts['spam'];

return (object) $comment_counts;
	}

/**
	 * Make sure WP displays avatars for comments with the `review` type.
	 *
	 * @since  2.3
	 * @param  array $comment_types Comment types.
	 * @return array
	 */
	public static function add_avatar_for_review_comment_type( $comment_types ) {
		return array_merge( $comment_types, array( 'review' ) );
	}

/**
	 * Add Product Reviews filter for `review` comment type.
	 *
	 * @since 6.0.0
	 *
	 * @param array $comment_types Array of comment type labels keyed by their name.
	 *
	 * @return array
	 */
	public static function add_review_comment_filter( array $comment_types ): array {
		$comment_types['review'] = __( 'Product Reviews', 'woocommerce' );
		return $comment_types;
	}

/**
	 * Determine if a review is from a verified owner at submission.
	 *
	 * @param int $comment_id Comment ID.
	 * @return bool
	 */
	public static function add_comment_purchase_verification( $comment_id ) {
		$comment  = get_comment( $comment_id );
		$verified = false;
		if ( 'product' === get_post_type( $comment->comment_post_ID ) ) {
			// When possible, narrow down wc_customer_bought_product inputs for better performance.
			$email    = $comment->user_id ? '' : $comment->comment_author_email;
			$verified = wc_customer_bought_product( $email, $comment->user_id, $comment->comment_post_ID );
			add_comment_meta( $comment_id, 'verified', (int) $verified, true );
		}
		return $verified;
	}

/**
	 * Get product rating for a product. Please note this is not cached.
	 *
	 * @since 3.0.0
	 * @param WC_Product $product Product instance.
	 * @return float
	 */
	public static function get_average_rating_for_product( &$product ) {
		global $wpdb;

$count = $product->get_rating_count();

if ( $count ) {
			$ratings = $wpdb->get_var(
				$wpdb->prepare(
					"
				SELECT SUM(meta_value) FROM $wpdb->commentmeta
				LEFT JOIN $wpdb->comments ON $wpdb->commentmeta.comment_id = $wpdb->comments.comment_ID
				WHERE meta_key = 'rating'
				AND comment_post_ID = %d
				AND comment_approved = '1'
				AND meta_value > 0
					",
					$product->get_id()
				)
			);
			$average = number_format( $ratings / $count, 2, '.', '' );
		} else {
			$average = 0;
		}

return $average;
	}

/**
	 * Utility function for getting review counts for multiple products in one query. This is not cached.
	 *
	 * @since 5.0.0
	 *
	 * @param array $product_ids Array of product IDs.
	 *
	 * @return array
	 */
	public static function get_review_counts_for_product_ids( $product_ids ) {
		global $wpdb;

if ( empty( $product_ids ) ) {
			return array();
		}

$product_id_string_placeholder = substr( str_repeat( ',%s', count( $product_ids ) ), 1 );

$review_counts = $wpdb->get_results(
			// phpcs:disable WordPress.DB.PreparedSQL.InterpolatedNotPrepared -- Ignored for allowing interpolation in IN query.
			$wpdb->prepare(
				"
					SELECT comment_post_ID as product_id, COUNT( comment_post_ID ) as review_count
					FROM $wpdb->comments
					WHERE
						comment_parent = 0
						AND comment_post_ID IN ( $product_id_string_placeholder )
						AND comment_approved = '1'
						AND comment_type in ( 'review', '', 'comment' )
					GROUP BY product_id
				",
				$product_ids
			),
			// phpcs:enable WordPress.DB.PreparedSQL.InterpolatedNotPrepared.
			ARRAY_A
		);

// Convert to key value pairs.
		$counts = array_replace( array_fill_keys( $product_ids, 0 ), array_column( $review_counts, 'review_count', 'product_id' ) );

return $counts;
	}

/**
	 * Get product review count for a product (not replies). Please note this is not cached.
	 *
	 * @since 3.0.0
	 * @param WC_Product $product Product instance.
	 * @return int
	 */
	public static function get_review_count_for_product( &$product ) {
		$counts = self::get_review_counts_for_product_ids( array( $product->get_id() ) );

return $counts[ $product->get_id() ];
	}

/**
	 * Get product rating count for a product. Please note this is not cached.
	 *
	 * @since 3.0.0
	 * @param WC_Product $product Product instance.
	 * @return int[]
	 */
	public static function get_rating_counts_for_product( &$product ) {
		global $wpdb;

$counts     = array();
		$raw_counts = $wpdb->get_results(
			$wpdb->prepare(
				"
			SELECT meta_value, COUNT( * ) as meta_value_count FROM $wpdb->commentmeta
			LEFT JOIN $wpdb->comments ON $wpdb->commentmeta.comment_id = $wpdb->comments.comment_ID
			WHERE meta_key = 'rating'
			AND comment_post_ID = %d
			AND comment_approved = '1'
			AND meta_value > 0
			GROUP BY meta_value
				",
				$product->get_id()
			)
		);

foreach ( $raw_counts as $count ) {
			$counts[ $count->meta_value ] = absint( $count->meta_value_count ); // WPCS: slow query ok.
		}

return $counts;
	}

/**
	 * Update comment type of product reviews.
	 *
	 * @since 3.5.0
	 * @param array $comment_data Comment data.
	 * @return array
	 */
	public static function update_comment_type( $comment_data ) {
		if ( ! is_admin() && isset( $_POST['comment_post_ID'], $comment_data['comment_type'] ) && self::is_default_comment_type( $comment_data['comment_type'] ) && 'product' === get_post_type( absint( $_POST['comment_post_ID'] ) ) ) { // WPCS: input var ok, CSRF ok.
			$comment_data['comment_type'] = 'review';
		}

return $comment_data;
	}

/**
	 * Validate product reviews if requires a verified owner.
	 *
	 * @param int $comment_post_id Post ID.
	 */
	public static function validate_product_review_verified_owners( $comment_post_id ) {
		// Only validate if option is enabled.
		if ( 'yes' !== get_option( 'woocommerce_review_rating_verification_required' ) ) {
			return;
		}

// Validate only products.
		if ( 'product' !== get_post_type( $comment_post_id ) ) {
			return;
		}

// Skip if is a verified owner.
		if ( wc_customer_bought_product( '', get_current_user_id(), $comment_post_id ) ) {
			return;
		}

wp_die(
			esc_html__( 'Only logged in customers who have purchased this product may leave a review.', 'woocommerce' ),
			esc_html__( 'Reviews can only be left by "verified owners"', 'woocommerce' ),
			array(
				'code' => 403,
			)
		);
	}

/**
	 * Determines if a comment is of the default type.
	 *
	 * Prior to WordPress 5.5, '' was the default comment type.
	 * As of 5.5, the default type is 'comment'.
	 *
	 * @since 4.3.0
	 * @param string $comment_type Comment type.
	 * @return bool
	 */
	private static function is_default_comment_type( $comment_type ) {
		return ( '' === $comment_type || 'comment' === $comment_type );
	}
}

WC_Comments::init();