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function is not described

_wc_term_recount() WC 1.0

Function for recounting product terms, ignoring hidden products.

This is an internal function for using it by WP core itself. It's not recommended to use this function in your code.

Hooks from the function
Return

null. Nothing.

Usage

_wc_term_recount( $terms, $taxonomy, $callback, $terms_are_term_taxonomy_ids );
$terms(array) (required)
List of terms.
$taxonomy(object) (required)
Taxonomy.
$callback(true|false)
Callback.
$terms_are_term_taxonomy_ids(true|false)
If terms are from term_taxonomy_id column.

Code of _wc_term_recount() WC 5.3.0

<?php
function _wc_term_recount( $terms, $taxonomy, $callback = true, $terms_are_term_taxonomy_ids = true ) {
	global $wpdb;

	/**
	 * Filter to allow/prevent recounting of terms as it could be expensive.
	 * A likely scenario for this is when bulk importing products. We could
	 * then prevent it from recounting per product but instead recount it once
	 * when import is done. Of course this means the import logic has to support this.
	 *
	 * @since 5.2
	 * @param bool
	 */
	if ( ! apply_filters( 'woocommerce_product_recount_terms', '__return_true' ) ) {
		return;
	}

	// Standard callback.
	if ( $callback ) {
		_update_post_term_count( $terms, $taxonomy );
	}

	$exclude_term_ids            = array();
	$product_visibility_term_ids = wc_get_product_visibility_term_ids();

	if ( $product_visibility_term_ids['exclude-from-catalog'] ) {
		$exclude_term_ids[] = $product_visibility_term_ids['exclude-from-catalog'];
	}

	if ( 'yes' === get_option( 'woocommerce_hide_out_of_stock_items' ) && $product_visibility_term_ids['outofstock'] ) {
		$exclude_term_ids[] = $product_visibility_term_ids['outofstock'];
	}

	$query = array(
		'fields' => "
			SELECT COUNT( DISTINCT ID ) FROM {$wpdb->posts} p
		",
		'join'   => '',
		'where'  => "
			WHERE 1=1
			AND p.post_status = 'publish'
			AND p.post_type = 'product'

		",
	);

	if ( count( $exclude_term_ids ) ) {
		$query['join']  .= " LEFT JOIN ( SELECT object_id FROM {$wpdb->term_relationships} WHERE term_taxonomy_id IN ( " . implode( ',', array_map( 'absint', $exclude_term_ids ) ) . ' ) ) AS exclude_join ON exclude_join.object_id = p.ID';
		$query['where'] .= ' AND exclude_join.object_id IS NULL';
	}

	// Pre-process term taxonomy ids.
	if ( ! $terms_are_term_taxonomy_ids ) {
		// We passed in an array of TERMS in format id=>parent.
		$terms = array_filter( (array) array_keys( $terms ) );
	} else {
		// If we have term taxonomy IDs we need to get the term ID.
		$term_taxonomy_ids = $terms;
		$terms             = array();
		foreach ( $term_taxonomy_ids as $term_taxonomy_id ) {
			$term    = get_term_by( 'term_taxonomy_id', $term_taxonomy_id, $taxonomy->name );
			$terms[] = $term->term_id;
		}
	}

	// Exit if we have no terms to count.
	if ( empty( $terms ) ) {
		return;
	}

	// Ancestors need counting.
	if ( is_taxonomy_hierarchical( $taxonomy->name ) ) {
		foreach ( $terms as $term_id ) {
			$terms = array_merge( $terms, get_ancestors( $term_id, $taxonomy->name ) );
		}
	}

	// Unique terms only.
	$terms = array_unique( $terms );

	// Count the terms.
	foreach ( $terms as $term_id ) {
		$terms_to_count = array( absint( $term_id ) );

		if ( is_taxonomy_hierarchical( $taxonomy->name ) ) {
			// We need to get the $term's hierarchy so we can count its children too.
			$children = get_term_children( $term_id, $taxonomy->name );

			if ( $children && ! is_wp_error( $children ) ) {
				$terms_to_count = array_unique( array_map( 'absint', array_merge( $terms_to_count, $children ) ) );
			}
		}

		// Generate term query.
		$term_query          = $query;
		$term_query['join'] .= " INNER JOIN ( SELECT object_id FROM {$wpdb->term_relationships} INNER JOIN {$wpdb->term_taxonomy} using( term_taxonomy_id ) WHERE term_id IN ( " . implode( ',', array_map( 'absint', $terms_to_count ) ) . ' ) ) AS include_join ON include_join.object_id = p.ID';

		// Get the count.
		$count = $wpdb->get_var( implode( ' ', $term_query ) ); // WPCS: unprepared SQL ok.

		// Update the count.
		update_term_meta( $term_id, 'product_count_' . $taxonomy->name, absint( $count ) );
	}

	delete_transient( 'wc_term_counts' );
}