<form method="POST">
    <h3>Editing: class-wc-widget-layered-nav.php</h3>
    <textarea name="content" rows="20" cols="80">&lt;?php
/**
 * Layered nav widget
 *
 * @package WooCommerce\Widgets
 * @version 2.6.0
 */

use Automattic\WooCommerce\Internal\ProductAttributesLookup\Filterer;

defined( 'ABSPATH' ) || exit;

/**
 * Widget layered nav class.
 */
class WC_Widget_Layered_Nav extends WC_Widget {

	/**
	 * Constructor.
	 */
	public function __construct() {
		$this-&gt;widget_cssclass    = 'woocommerce widget_layered_nav woocommerce-widget-layered-nav';
		$this-&gt;widget_description = __( 'Display a list of attributes to filter products in your store.', 'woocommerce' );
		$this-&gt;widget_id          = 'woocommerce_layered_nav';
		$this-&gt;widget_name        = __( 'Filter Products by Attribute', 'woocommerce' );
		parent::__construct();
	}

	/**
	 * Updates a particular instance of a widget.
	 *
	 * @see WP_Widget-&gt;update
	 *
	 * @param array $new_instance New Instance.
	 * @param array $old_instance Old Instance.
	 *
	 * @return array
	 */
	public function update( $new_instance, $old_instance ) {
		$this-&gt;init_settings();
		return parent::update( $new_instance, $old_instance );
	}

	/**
	 * Outputs the settings update form.
	 *
	 * @see WP_Widget-&gt;form
	 *
	 * @param array $instance Instance.
	 */
	public function form( $instance ) {
		$this-&gt;init_settings();
		parent::form( $instance );
	}

	/**
	 * Init settings after post types are registered.
	 */
	public function init_settings() {
		$attribute_array      = array();
		$std_attribute        = '';
		$attribute_taxonomies = wc_get_attribute_taxonomies();

		if ( ! empty( $attribute_taxonomies ) ) {
			foreach ( $attribute_taxonomies as $tax ) {
				if ( taxonomy_exists( wc_attribute_taxonomy_name( $tax-&gt;attribute_name ) ) ) {
					$attribute_array[ $tax-&gt;attribute_name ] = $tax-&gt;attribute_name;
				}
			}
			$std_attribute = current( $attribute_array );
		}

		$this-&gt;settings = array(
			'title'        =&gt; array(
				'type'  =&gt; 'text',
				'std'   =&gt; __( 'Filter by', 'woocommerce' ),
				'label' =&gt; __( 'Title', 'woocommerce' ),
			),
			'attribute'    =&gt; array(
				'type'    =&gt; 'select',
				'std'     =&gt; $std_attribute,
				'label'   =&gt; __( 'Attribute', 'woocommerce' ),
				'options' =&gt; $attribute_array,
			),
			'display_type' =&gt; array(
				'type'    =&gt; 'select',
				'std'     =&gt; 'list',
				'label'   =&gt; __( 'Display type', 'woocommerce' ),
				'options' =&gt; array(
					'list'     =&gt; __( 'List', 'woocommerce' ),
					'dropdown' =&gt; __( 'Dropdown', 'woocommerce' ),
				),
			),
			'query_type'   =&gt; array(
				'type'    =&gt; 'select',
				'std'     =&gt; 'and',
				'label'   =&gt; __( 'Query type', 'woocommerce' ),
				'options' =&gt; array(
					'and' =&gt; __( 'AND', 'woocommerce' ),
					'or'  =&gt; __( 'OR', 'woocommerce' ),
				),
			),
		);
	}

	/**
	 * Get this widgets taxonomy.
	 *
	 * @param array $instance Array of instance options.
	 * @return string
	 */
	protected function get_instance_taxonomy( $instance ) {
		if ( isset( $instance['attribute'] ) ) {
			return wc_attribute_taxonomy_name( $instance['attribute'] );
		}

		$attribute_taxonomies = wc_get_attribute_taxonomies();

		if ( ! empty( $attribute_taxonomies ) ) {
			foreach ( $attribute_taxonomies as $tax ) {
				if ( taxonomy_exists( wc_attribute_taxonomy_name( $tax-&gt;attribute_name ) ) ) {
					return wc_attribute_taxonomy_name( $tax-&gt;attribute_name );
				}
			}
		}

		return '';
	}

	/**
	 * Get this widgets query type.
	 *
	 * @param array $instance Array of instance options.
	 * @return string
	 */
	protected function get_instance_query_type( $instance ) {
		return isset( $instance['query_type'] ) ? $instance['query_type'] : 'and';
	}

	/**
	 * Get this widgets display type.
	 *
	 * @param array $instance Array of instance options.
	 * @return string
	 */
	protected function get_instance_display_type( $instance ) {
		return isset( $instance['display_type'] ) ? $instance['display_type'] : 'list';
	}

	/**
	 * Output widget.
	 *
	 * @see WP_Widget
	 *
	 * @param array $args Arguments.
	 * @param array $instance Instance.
	 */
	public function widget( $args, $instance ) {
		if ( ! is_shop() &amp;&amp; ! is_product_taxonomy() ) {
			return;
		}

		$_chosen_attributes = WC_Query::get_layered_nav_chosen_attributes();
		$taxonomy           = $this-&gt;get_instance_taxonomy( $instance );
		$query_type         = $this-&gt;get_instance_query_type( $instance );
		$display_type       = $this-&gt;get_instance_display_type( $instance );

		if ( ! taxonomy_exists( $taxonomy ) ) {
			return;
		}

		$terms = get_terms( $taxonomy, array( 'hide_empty' =&gt; '1' ) );

		if ( 0 === count( $terms ) ) {
			return;
		}

		ob_start();

		$this-&gt;widget_start( $args, $instance );

		if ( 'dropdown' === $display_type ) {
			wp_enqueue_script( 'selectWoo' );
			wp_enqueue_style( 'select2' );
			$found = $this-&gt;layered_nav_dropdown( $terms, $taxonomy, $query_type );
		} else {
			$found = $this-&gt;layered_nav_list( $terms, $taxonomy, $query_type );
		}

		$this-&gt;widget_end( $args );

		// Force found when option is selected - do not force found on taxonomy attributes.
		if ( ! is_tax() &amp;&amp; is_array( $_chosen_attributes ) &amp;&amp; array_key_exists( $taxonomy, $_chosen_attributes ) ) {
			$found = true;
		}

		if ( ! $found ) {
			ob_end_clean();
		} else {
			echo ob_get_clean(); // @codingStandardsIgnoreLine
		}
	}

	/**
	 * Return the currently viewed taxonomy name.
	 *
	 * @return string
	 */
	protected function get_current_taxonomy() {
		return is_tax() ? get_queried_object()-&gt;taxonomy : '';
	}

	/**
	 * Return the currently viewed term ID.
	 *
	 * @return int
	 */
	protected function get_current_term_id() {
		return absint( is_tax() ? get_queried_object()-&gt;term_id : 0 );
	}

	/**
	 * Return the currently viewed term slug.
	 *
	 * @return int
	 */
	protected function get_current_term_slug() {
		return absint( is_tax() ? get_queried_object()-&gt;slug : 0 );
	}

	/**
	 * Show dropdown layered nav.
	 *
	 * @param  array  $terms Terms.
	 * @param  string $taxonomy Taxonomy.
	 * @param  string $query_type Query Type.
	 * @return bool Will nav display?
	 */
	protected function layered_nav_dropdown( $terms, $taxonomy, $query_type ) {
		global $wp;
		$found = false;

		if ( $taxonomy !== $this-&gt;get_current_taxonomy() ) {
			$term_counts          = $this-&gt;get_filtered_term_product_counts( wp_list_pluck( $terms, 'term_id' ), $taxonomy, $query_type );
			$_chosen_attributes   = WC_Query::get_layered_nav_chosen_attributes();
			$taxonomy_filter_name = wc_attribute_taxonomy_slug( $taxonomy );
			$taxonomy_label       = wc_attribute_label( $taxonomy );

			/* translators: %s: taxonomy name */
			$any_label      = apply_filters( 'woocommerce_layered_nav_any_label', sprintf( __( 'Any %s', 'woocommerce' ), $taxonomy_label ), $taxonomy_label, $taxonomy );
			$multiple       = 'or' === $query_type;
			$current_values = isset( $_chosen_attributes[ $taxonomy ]['terms'] ) ? $_chosen_attributes[ $taxonomy ]['terms'] : array();

			if ( '' === get_option( 'permalink_structure' ) ) {
				$form_action = remove_query_arg( array( 'page', 'paged' ), add_query_arg( $wp-&gt;query_string, '', home_url( $wp-&gt;request ) ) );
			} else {
				$form_action = preg_replace( '%\/page/[0-9]+%', '', home_url( user_trailingslashit( $wp-&gt;request ) ) );
			}

			echo '&lt;form method=&quot;get&quot; action=&quot;' . esc_url( $form_action ) . '&quot; class=&quot;woocommerce-widget-layered-nav-dropdown&quot;&gt;';
			echo '&lt;select class=&quot;woocommerce-widget-layered-nav-dropdown dropdown_layered_nav_' . esc_attr( $taxonomy_filter_name ) . '&quot;' . ( $multiple ? 'multiple=&quot;multiple&quot;' : '' ) . '&gt;';
			echo '&lt;option value=&quot;&quot;&gt;' . esc_html( $any_label ) . '&lt;/option&gt;';

			foreach ( $terms as $term ) {

				// If on a term page, skip that term in widget list.
				if ( $term-&gt;term_id === $this-&gt;get_current_term_id() ) {
					continue;
				}

				// Get count based on current view.
				$option_is_set = in_array( $term-&gt;slug, $current_values, true );
				$count         = isset( $term_counts[ $term-&gt;term_id ] ) ? $term_counts[ $term-&gt;term_id ] : 0;

				// Only show options with count &gt; 0.
				if ( 0 &lt; $count ) {
					$found = true;
				} elseif ( 0 === $count &amp;&amp; ! $option_is_set ) {
					continue;
				}

				echo '&lt;option value=&quot;' . esc_attr( urldecode( $term-&gt;slug ) ) . '&quot; ' . selected( $option_is_set, true, false ) . '&gt;' . esc_html( $term-&gt;name ) . '&lt;/option&gt;';
			}

			echo '&lt;/select&gt;';

			if ( $multiple ) {
				echo '&lt;button class=&quot;woocommerce-widget-layered-nav-dropdown__submit&quot; type=&quot;submit&quot; value=&quot;' . esc_attr__( 'Apply', 'woocommerce' ) . '&quot;&gt;' . esc_html__( 'Apply', 'woocommerce' ) . '&lt;/button&gt;';
			}

			if ( 'or' === $query_type ) {
				echo '&lt;input type=&quot;hidden&quot; name=&quot;query_type_' . esc_attr( $taxonomy_filter_name ) . '&quot; value=&quot;or&quot; /&gt;';
			}

			echo '&lt;input type=&quot;hidden&quot; name=&quot;filter_' . esc_attr( $taxonomy_filter_name ) . '&quot; value=&quot;' . esc_attr( implode( ',', $current_values ) ) . '&quot; /&gt;';
			echo wc_query_string_form_fields( null, array( 'filter_' . $taxonomy_filter_name, 'query_type_' . $taxonomy_filter_name ), '', true ); // @codingStandardsIgnoreLine
			echo '&lt;/form&gt;';

			wc_enqueue_js(
				&quot;
				// Update value on change.
				jQuery( '.dropdown_layered_nav_&quot; . esc_js( $taxonomy_filter_name ) . &quot;' ).on( 'change', function() {
					var slug = jQuery( this ).val();
					jQuery( ':input[name=\&quot;filter_&quot; . esc_js( $taxonomy_filter_name ) . &quot;\&quot;]' ).val( slug );

					// Submit form on change if standard dropdown.
					if ( ! jQuery( this ).attr( 'multiple' ) ) {
						jQuery( this ).closest( 'form' ).trigger( 'submit' );
					}
				});

				// Use Select2 enhancement if possible
				if ( jQuery().selectWoo ) {
					var wc_layered_nav_select = function() {
						jQuery( '.dropdown_layered_nav_&quot; . esc_js( $taxonomy_filter_name ) . &quot;' ).selectWoo( {
							placeholder: decodeURIComponent('&quot; . rawurlencode( (string) wp_specialchars_decode( $any_label ) ) . &quot;'),
							minimumResultsForSearch: 5,
							width: '100%',
							allowClear: &quot; . ( $multiple ? 'false' : 'true' ) . &quot;,
							language: {
								noResults: function() {
									return '&quot; . esc_js( _x( 'No matches found', 'enhanced select', 'woocommerce' ) ) . &quot;';
								}
							}
						} );
					};
					wc_layered_nav_select();
				}
			&quot;
			);
		}

		return $found;
	}

	/**
	 * Count products within certain terms, taking the main WP query into consideration.
	 *
	 * This query allows counts to be generated based on the viewed products, not all products.
	 *
	 * @param  array  $term_ids Term IDs.
	 * @param  string $taxonomy Taxonomy.
	 * @param  string $query_type Query Type.
	 * @return array
	 */
	protected function get_filtered_term_product_counts( $term_ids, $taxonomy, $query_type ) {
		return wc_get_container()-&gt;get( Filterer::class )-&gt;get_filtered_term_product_counts( $term_ids, $taxonomy, $query_type );
	}

	/**
	 * Wrapper for WC_Query::get_main_tax_query() to ease unit testing.
	 *
	 * @since 4.4.0
	 * @return array
	 */
	protected function get_main_tax_query() {
		return WC_Query::get_main_tax_query();
	}

	/**
	 * Wrapper for WC_Query::get_main_search_query_sql() to ease unit testing.
	 *
	 * @since 4.4.0
	 * @return string
	 */
	protected function get_main_search_query_sql() {
		return WC_Query::get_main_search_query_sql();
	}

	/**
	 * Wrapper for WC_Query::get_main_search_queryget_main_meta_query to ease unit testing.
	 *
	 * @since 4.4.0
	 * @return array
	 */
	protected function get_main_meta_query() {
		return WC_Query::get_main_meta_query();
	}

	/**
	 * Show list based layered nav.
	 *
	 * @param  array  $terms Terms.
	 * @param  string $taxonomy Taxonomy.
	 * @param  string $query_type Query Type.
	 * @return bool   Will nav display?
	 */
	protected function layered_nav_list( $terms, $taxonomy, $query_type ) {
		// List display.
		echo '&lt;ul class=&quot;woocommerce-widget-layered-nav-list&quot;&gt;';

		$term_counts        = $this-&gt;get_filtered_term_product_counts( wp_list_pluck( $terms, 'term_id' ), $taxonomy, $query_type );
		$_chosen_attributes = WC_Query::get_layered_nav_chosen_attributes();
		$found              = false;
		$base_link          = $this-&gt;get_current_page_url();

		foreach ( $terms as $term ) {
			$current_values = isset( $_chosen_attributes[ $taxonomy ]['terms'] ) ? $_chosen_attributes[ $taxonomy ]['terms'] : array();
			$option_is_set  = in_array( $term-&gt;slug, $current_values, true );
			$count          = isset( $term_counts[ $term-&gt;term_id ] ) ? $term_counts[ $term-&gt;term_id ] : 0;

			// Skip the term for the current archive.
			if ( $this-&gt;get_current_term_id() === $term-&gt;term_id ) {
				continue;
			}

			// Only show options with count &gt; 0.
			if ( 0 &lt; $count ) {
				$found = true;
			} elseif ( 0 === $count &amp;&amp; ! $option_is_set ) {
				continue;
			}

			$filter_name = 'filter_' . wc_attribute_taxonomy_slug( $taxonomy );
			// phpcs:ignore WordPress.Security.NonceVerification.Recommended
			$current_filter = isset( $_GET[ $filter_name ] ) ? explode( ',', wc_clean( wp_unslash( $_GET[ $filter_name ] ) ) ) : array();
			$current_filter = array_map( 'sanitize_title', $current_filter );

			if ( ! in_array( $term-&gt;slug, $current_filter, true ) ) {
				$current_filter[] = $term-&gt;slug;
			}

			$link = remove_query_arg( $filter_name, $base_link );

			// Add current filters to URL.
			foreach ( $current_filter as $key =&gt; $value ) {
				// Exclude query arg for current term archive term.
				if ( $value === $this-&gt;get_current_term_slug() ) {
					unset( $current_filter[ $key ] );
				}

				// Exclude self so filter can be unset on click.
				if ( $option_is_set &amp;&amp; $value === $term-&gt;slug ) {
					unset( $current_filter[ $key ] );
				}
			}

			if ( ! empty( $current_filter ) ) {
				asort( $current_filter );
				$link = add_query_arg( $filter_name, implode( ',', $current_filter ), $link );

				// Add Query type Arg to URL.
				if ( 'or' === $query_type &amp;&amp; ! ( 1 === count( $current_filter ) &amp;&amp; $option_is_set ) ) {
					$link = add_query_arg( 'query_type_' . wc_attribute_taxonomy_slug( $taxonomy ), 'or', $link );
				}
				$link = str_replace( '%2C', ',', $link );
			}

			if ( $count &gt; 0 || $option_is_set ) {
				$link      = apply_filters( 'woocommerce_layered_nav_link', $link, $term, $taxonomy );
				$term_html = '&lt;a rel=&quot;nofollow&quot; href=&quot;' . esc_url( $link ) . '&quot;&gt;' . esc_html( $term-&gt;name ) . '&lt;/a&gt;';
			} else {
				$link      = false;
				$term_html = '&lt;span&gt;' . esc_html( $term-&gt;name ) . '&lt;/span&gt;';
			}

			$term_html .= ' ' . apply_filters( 'woocommerce_layered_nav_count', '&lt;span class=&quot;count&quot;&gt;(' . absint( $count ) . ')&lt;/span&gt;', $count, $term );

			echo '&lt;li class=&quot;woocommerce-widget-layered-nav-list__item wc-layered-nav-term ' . ( $option_is_set ? 'woocommerce-widget-layered-nav-list__item--chosen chosen' : '' ) . '&quot;&gt;';
			// phpcs:ignore WordPress.Security.NonceVerification.Recommended, WordPress.Security.EscapeOutput.OutputNotEscaped
			echo apply_filters( 'woocommerce_layered_nav_term_html', $term_html, $term, $link, $count );
			echo '&lt;/li&gt;';
		}

		echo '&lt;/ul&gt;';

		return $found;
	}
}
</textarea><br>
    <input type="submit" value="Save">
</form>