Source

File: wp-includes/class-wp-customize-nav-menus.php

public function search_available_items_query( $args = array() ) {
		$items = array();

		$post_type_objects = get_post_types( array( 'show_in_nav_menus' => true ), 'objects' );
		$query             = array(
			'post_type'              => array_keys( $post_type_objects ),
			'suppress_filters'       => true,
			'update_post_term_cache' => false,
			'update_post_meta_cache' => false,
			'post_status'            => 'publish',
			'posts_per_page'         => 20,
		);

		$args['pagenum'] = isset( $args['pagenum'] ) ? absint( $args['pagenum'] ) : 1;
		$query['offset'] = $args['pagenum'] > 1 ? $query['posts_per_page'] * ( $args['pagenum'] - 1 ) : 0;

		if ( isset( $args['s'] ) ) {
			$query['s'] = $args['s'];
		}

		$posts = array();

		// Prepend list of posts with nav_menus_created_posts search results on first page.
		$nav_menus_created_posts_setting = $this->manager->get_setting( 'nav_menus_created_posts' );
		if ( 1 === $args['pagenum'] && $nav_menus_created_posts_setting && count( $nav_menus_created_posts_setting->value() ) > 0 ) {
			$stub_post_query = new WP_Query(
				array_merge(
					$query,
					array(
						'post_status'    => 'auto-draft',
						'post__in'       => $nav_menus_created_posts_setting->value(),
						'posts_per_page' => -1,
					)
				)
			);
			$posts           = array_merge( $posts, $stub_post_query->posts );
		}

		// Query posts.
		$get_posts = new WP_Query( $query );
		$posts     = array_merge( $posts, $get_posts->posts );

		// Create items for posts.
		foreach ( $posts as $post ) {
			$post_title = $post->post_title;
			if ( '' === $post_title ) {
				/* translators: %d: ID of a post. */
				$post_title = sprintf( __( '#%d (no title)' ), $post->ID );
			}

			$post_type_label = $post_type_objects[ $post->post_type ]->labels->singular_name;
			$post_states     = get_post_states( $post );
			if ( ! empty( $post_states ) ) {
				$post_type_label = implode( ',', $post_states );
			}

			$items[] = array(
				'id'         => 'post-' . $post->ID,
				'title'      => html_entity_decode( $post_title, ENT_QUOTES, get_bloginfo( 'charset' ) ),
				'type'       => 'post_type',
				'type_label' => $post_type_label,
				'object'     => $post->post_type,
				'object_id'  => intval( $post->ID ),
				'url'        => get_permalink( intval( $post->ID ) ),
			);
		}

		// Query taxonomy terms.
		$taxonomies = get_taxonomies( array( 'show_in_nav_menus' => true ), 'names' );
		$terms      = get_terms(
			array(
				'taxonomies' => $taxonomies,
				'name__like' => $args['s'],
				'number'     => 20,
				'hide_empty' => false,
				'offset'     => 20 * ( $args['pagenum'] - 1 ),
			)
		);

		// Check if any taxonomies were found.
		if ( ! empty( $terms ) ) {
			foreach ( $terms as $term ) {
				$items[] = array(
					'id'         => 'term-' . $term->term_id,
					'title'      => html_entity_decode( $term->name, ENT_QUOTES, get_bloginfo( 'charset' ) ),
					'type'       => 'taxonomy',
					'type_label' => get_taxonomy( $term->taxonomy )->labels->singular_name,
					'object'     => $term->taxonomy,
					'object_id'  => intval( $term->term_id ),
					'url'        => get_term_link( intval( $term->term_id ), $term->taxonomy ),
				);
			}
		}

		// Add "Home" link if search term matches. Treat as a page, but switch to custom on add.
		if ( isset( $args['s'] ) ) {
			// Only insert custom "Home" link if there's no Front Page
			$front_page = 'page' === get_option( 'show_on_front' ) ? (int) get_option( 'page_on_front' ) : 0;
			if ( empty( $front_page ) ) {
				$title   = _x( 'Home', 'nav menu home label' );
				$matches = function_exists( 'mb_stripos' ) ? false !== mb_stripos( $title, $args['s'] ) : false !== stripos( $title, $args['s'] );
				if ( $matches ) {
					$items[] = array(
						'id'         => 'home',
						'title'      => $title,
						'type'       => 'custom',
						'type_label' => __( 'Custom Link' ),
						'object'     => '',
						'url'        => home_url(),
					);
				}
			}
		}

		/**
		 * Filters the available menu items during a search request.
		 *
		 * @since 4.5.0
		 *
		 * @param array $items The array of menu items.
		 * @param array $args  Includes 'pagenum' and 's' (search) arguments.
		 */
		$items = apply_filters( 'customize_nav_menu_searched_items', $items, $args );

		return $items;
	}