wp-includes/post.php:5328Computes a unique slug for the post, when given the desired slug and some post details.
$slugstring$post_idint$post_statusstring$post_typestring$post_parentintstring5 hooks fire while wp_unique_post_slug() runs, in this order:
Filters the post slug before it is generated to be unique.
Filters whether the post slug would make a bad attachment slug.
Filters whether the post slug would make a bad hierarchical post slug.
Filters whether the post slug would be bad as a flat slug.
Filters the unique post slug.
function wp_unique_post_slug( $slug, $post_id, $post_status, $post_type, $post_parent ) { if ( in_array( $post_status, array( 'draft', 'pending', 'auto-draft' ), true ) || ( 'inherit' === $post_status && 'revision' === $post_type ) || 'user_request' === $post_type ) { return $slug; } /** * Filters the post slug before it is generated to be unique. * * Returning a non-null value will short-circuit the * unique slug generation, returning the passed value instead. * * @since 5.1.0 * * @param string|null $override_slug Short-circuit return value. * @param string $slug The desired slug (post_name). * @param int $post_id Post ID. * @param string $post_status The post status. * @param string $post_type Post type. * @param int $post_parent Post parent ID. */ $override_slug = apply_filters( 'pre_wp_unique_post_slug', null, $slug, $post_id, $post_status, $post_type, $post_parent ); if ( null !== $override_slug ) { return $override_slug; } global $wpdb, $wp_rewrite; $original_slug = $slug; $feeds = $wp_rewrite->feeds; if ( ! is_array( $feeds ) ) { $feeds = array(); } if ( 'attachment' === $post_type ) { // Attachment slugs must be unique across all types. $check_sql = "SELECT post_name FROM $wpdb->posts WHERE post_name = %s AND ID != %d LIMIT 1"; $post_name_check = $wpdb->get_var( $wpdb->prepare( $check_sql, $slug, $post_id ) ); /** * Filters whether the post slug would make a bad attachment slug. * * @since 3.1.0 * * @param bool $bad_slug Whether the slug would be bad as an attachment slug. * @param string $slug The post slug. */ $is_bad_attachment_slug = apply_filters( 'wp_unique_post_slug_is_bad_attachment_slug', false, $slug ); if ( $post_name_check || in_array( $slug, $feeds, true ) || 'embed' === $slug || $is_bad_attachment_slug ) { $suffix = 2; do { $alt_post_name = _truncate_post_slug( $slug, 200 - ( strlen( $suffix ) + 1 ) ) . "-$suffix"; $post_name_check = $wpdb->get_var( $wpdb->prepare( $check_sql, $alt_post_name, $post_id ) ); ++$suffix; } while ( $post_name_check ); $slug = $alt_post_name; } } elseif ( is_post_type_hierarchical( $post_type ) ) { if ( 'nav_menu_item' === $post_type ) { return $slug; } /* * Page slugs must be unique within their own trees. Pages are in a separate * namespace than posts so page slugs are allowed to overlap post slugs. */ $check_sql = "SELECT post_name FROM $wpdb->posts WHERE post_name = %s AND post_type IN ( %s, 'attachment' ) AND ID != %d AND post_parent = %d LIMIT 1"; $post_name_check = $wpdb->get_var( $wpdb->prepare( $check_sql, $slug, $post_type, $post_id, $post_parent ) ); /** * Filters whether the post slug would make a bad hierarchical post slug. * * @since 3.1.0 *Introduced in 2.8.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/post.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.