Issue #864: Native WordPress widget support, including subclasses

amp.php

@@ -71,6 +71,7 @@ function amp_after_setup_theme() {
 	}
 
 	add_action( 'init', 'amp_init' );
+	add_action( 'widgets_init', 'AMP_Theme_Support::register_widgets' );
 	add_action( 'admin_init', 'AMP_Options_Manager::register_settings' );
 	add_filter( 'amp_post_template_analytics', 'amp_add_custom_analytics' );
 	add_action( 'wp_loaded', 'amp_post_meta_box' );

bin/add-test-widgets-to-sidebar.php

@@ -385,7 +385,12 @@ function amp_create_widget( $widget ) {
 		$title             = str_replace( '-', ' ', $title );
 		$settings['title'] = sprintf( 'Test %s Widget', ucwords( $title ) );
 	}
-	$widgets[] = $settings;
+
+	$number = max( array_keys( $widgets ) );
+	$number = max( 2, $number );
+	$number++;
+
+	$widgets[ $number ] = $settings;
 	update_option( $option_key, $widgets );
 }
 

includes/class-amp-autoloader.php

@@ -79,6 +79,9 @@ class AMP_Autoloader {
 		'AMP_Image_Dimension_Extractor'               => 'includes/utils/class-amp-image-dimension-extractor',
 		'AMP_String_Utils'                            => 'includes/utils/class-amp-string-utils',
 		'AMP_WP_Utils'                                => 'includes/utils/class-amp-wp-utils',
+		'AMP_Widget_Archives'                         => 'includes/widgets/class-amp-widget-archives',
+		'AMP_Widget_Categories'                       => 'includes/widgets/class-amp-widget-categories',
+		'AMP_Widget_Recent_Comments'                  => 'includes/widgets/class-amp-widget-recent-comments',
 		'WPCOM_AMP_Polldaddy_Embed'                   => 'wpcom/class-amp-polldaddy-embed',
 		'AMP_Test_Stub_Sanitizer'                     => 'tests/stubs',
 		'AMP_Test_World_Sanitizer'                    => 'tests/stubs',

includes/class-amp-theme-support.php

@@ -196,6 +196,29 @@ public static function register_hooks() {
 		// @todo Add character conversion.
 	}
 
+	/**
+	 * Register/override widgets.
+	 *
+	 * @global WP_Widget_Factory
+	 * @return void
+	 */
+	public static function register_widgets() {
+		global $wp_widget_factory;
+		foreach ( $wp_widget_factory->widgets as $registered_widget ) {
+			$registered_widget_class_name = get_class( $registered_widget );
+			if ( ! preg_match( '/^WP_Widget_(.+)$/', $registered_widget_class_name, $matches ) ) {
+				continue;
+			}
+			$amp_class_name = 'AMP_Widget_' . $matches[1];
+			if ( ! class_exists( $amp_class_name ) || is_a( $amp_class_name, $registered_widget_class_name ) ) {
+				continue;
+			}
+
+			unregister_widget( $registered_widget_class_name );
+			register_widget( $amp_class_name );
+		}
+	}
+
 	/**
 	 * Override $wp_styles as AMP_WP_Styles, ideally before first instantiated as WP_Styles.
 	 *
@@ -463,7 +486,7 @@ public static function get_amp_component_scripts() {
 		 *
 		 * @since 0.7
 		 *
-		 * @param string $amp_scripts AMP Component scripts, mapping component names to component source URLs.
+		 * @param array $amp_scripts AMP Component scripts, mapping component names to component source URLs.
 		 */
 		$amp_scripts = apply_filters( 'amp_component_scripts', $amp_scripts );
 

includes/widgets/class-amp-widget-archives.php

@@ -0,0 +1,122 @@
+<?php
+/**
+ * Class AMP_Widget_Archives
+ *
+ * @package AMP
+ */
+
+/**
+ * Class AMP_Widget_Archives
+ *
+ * @package AMP
+ */
+class AMP_Widget_Archives extends WP_Widget_Archives {
+
+	/**
+	 * AMP_Widget_Archives constructor.
+	 *
+	 * @return void.
+	 */
+	public function __construct() {
+		parent::__construct();
+		add_filter( 'amp_component_scripts', array( $this, 'form_script' ) );
+	}
+
+	/**
+	 * Add a form extension script for AMP to output.
+	 *
+	 * @param array $scripts The AMP scripts.
+	 * @return array $scripts The filtered AMP scripts.
+	 */
+	public function form_script( $scripts ) {
+		if ( ! isset( $scripts['amp-form'] ) ) {
+			$scripts['amp-form'] = 'https://cdn.ampproject.org/v0/amp-form-latest.js';
+		}
+		return $scripts;
+	}
+
+	/**
+	 * Echoes the markup of the widget.
+	 *
+	 * Mainly copied from WP_Widget_Archives::widget()
+	 * Changes include:
+	 * An id for the <form>.
+	 * More escaping.
+	 * The dropdown is now filtered with 'wp_dropdown_cats.'
+	 * This enables adding an 'on' attribute, with the id of the form.
+	 * So changing the dropdown value will redirect to the category page, with valid AMP.
+	 *
+	 * @param array $args Widget display data.
+	 * @param array $instance Data for widget.
+	 * @return void.
+	 */
+	public function widget( $args, $instance ) {
+		if ( ! is_amp_endpoint() ) {
+			parent::widget( $args, $instance );
+			return;
+		}
+
+		$c = ! empty( $instance['count'] ) ? '1' : '0';
+		$d = ! empty( $instance['dropdown'] ) ? '1' : '0';
+
+		/** This filter is documented in wp-includes/widgets/class-wp-widget-pages.php */
+		$title = apply_filters( 'widget_title', empty( $instance['title'] ) ? __( 'Archives', 'default' ) : $instance['title'], $instance, $this->id_base );
+		echo wp_kses_post( $args['before_widget'] );
+		if ( $title ) :
+			echo wp_kses_post( $args['before_title'] . $title . $args['after_title'] );
+		endif;
+
+		if ( $d ) :
+			$dropdown_id = "{$this->id_base}-dropdown-{$this->number}";
+			?>
+			<form action="<?php echo esc_url( home_url() ); ?>" method="get" id="widget-archives-dropdown-<?php echo esc_attr( $this->number ); ?>">
+				<label class="screen-reader-text" for="<?php echo esc_attr( $dropdown_id ); ?>"><?php echo esc_html( $title ); ?></label>
+				<select id="<?php echo esc_attr( $dropdown_id ); ?>" name="archive-dropdown" on="change:widget-archives-dropdown-<?php echo esc_attr( $this->number ); ?>.submit">
+					<?php
+
+					/** This filter is documented in wp-includes/widgets/class-wp-widget-archives.php */
+					$dropdown_args = apply_filters( 'widget_archives_dropdown_args', array(
+						'type'            => 'monthly',
+						'format'          => 'option',
+						'show_post_count' => $c,
+					) );
+
+					switch ( $dropdown_args['type'] ) {
+						case 'yearly':
+							$label = __( 'Select Year', 'default' );
+							break;
+						case 'monthly':
+							$label = __( 'Select Month', 'default' );
+							break;
+						case 'daily':
+							$label = __( 'Select Day', 'default' );
+							break;
+						case 'weekly':
+							$label = __( 'Select Week', 'default' );
+							break;
+						default:
+							$label = __( 'Select Post', 'default' );
+							break;
+					}
+					?>
+					<option value=""><?php echo esc_attr( $label ); ?></option>
+					<?php wp_get_archives( $dropdown_args ); ?>
+				</select>
+			</form>
+		<?php else : ?>
+			<ul>
+				<?php
+
+				/** This filter is documented in wp-includes/widgets/class-wp-widget-archives.php */
+				wp_get_archives( apply_filters( 'widget_archives_args', array(
+					'type'            => 'monthly',
+					'show_post_count' => $c,
+				) ) );
+				?>
+			</ul>
+		<?php
+		endif;
+		echo wp_kses_post( $args['after_widget'] );
+	}
+
+}

includes/widgets/class-amp-widget-categories.php

@@ -0,0 +1,112 @@
+<?php
+/**
+ * Class AMP_Widget_Categories
+ *
+ * @package AMP
+ */
+
+/**
+ * Class AMP_Widget_Categories
+ *
+ * @package AMP
+ */
+class AMP_Widget_Categories extends WP_Widget_Categories {
+
+	/**
+	 * AMP_Widget_Categories constructor.
+	 *
+	 * @return void.
+	 */
+	public function __construct() {
+		parent::__construct();
+		add_filter( 'amp_component_scripts', array( $this, 'form_script' ) );
+	}
+
+	/**
+	 * Add a form extension script for AMP to output.
+	 *
+	 * @param array $scripts The AMP scripts.
+	 * @return array $scripts The filtered AMP scripts.
+	 */
+	public function form_script( $scripts ) {
+		if ( ! isset( $scripts['amp-form'] ) ) {
+			$scripts['amp-form'] = 'https://cdn.ampproject.org/v0/amp-form-latest.js';
+		}
+		return $scripts;
+	}
+
+	/**
+	 * Adds an 'on' attribute to the category dropdown's <select>.
+	 *
+	 * @param string $dropdown The markup of the category dropdown.
+	 * @return string $dropdown The filtered markup of the dropdown.
+	 */
+	public function modify_select( $dropdown ) {
+		$new_select = sprintf( '<select on="change:widget-categories-dropdown-%d.submit"', esc_attr( $this->number ) );
+		return str_replace( '<select', $new_select, $dropdown );
+	}
+
+	/**
+	 * Echoes the markup of the widget.
+	 *
+	 * Mainly copied from WP_Widget_Categories::widget()
+	 * There's now an id for the <form>.
+	 * And the dropdown is now filtered with 'wp_dropdown_cats.'
+	 * This enables adding an 'on' attribute, with the id of the form.
+	 * So changing the dropdown value will redirect to the category page, with valid AMP.
+	 *
+	 * @param array $args Widget display data.
+	 * @param array $instance Data for widget.
+	 * @return void.
+	 */
+	public function widget( $args, $instance ) {
+		if ( ! is_amp_endpoint() ) {
+			parent::widget( $args, $instance );
+			return;
+		}
+
+		static $first_dropdown = true;
+		$title                 = ! empty( $instance['title'] ) ? $instance['title'] : __( 'Categories', 'default' );
+		/** This filter is documented in wp-includes/widgets/class-wp-widget-pages.php */
+		$title = apply_filters( 'widget_title', $title, $instance, $this->id_base );
+		$c     = ! empty( $instance['count'] ) ? '1' : '0';
+		$h     = ! empty( $instance['hierarchical'] ) ? '1' : '0';
+		$d     = ! empty( $instance['dropdown'] ) ? '1' : '0';
+		echo wp_kses_post( $args['before_widget'] );
+		if ( $title ) {
+			echo wp_kses_post( $args['before_title'] . $title . $args['after_title'] );
+		}
+		$cat_args = array(
+			'orderby'      => 'name',
+			'show_count'   => $c,
+			'hierarchical' => $h,
+		);
+		if ( $d ) :
+			echo sprintf( '<form action="%s" method="get" id="widget-categories-dropdown-%d">', esc_url( home_url() ), esc_attr( $this->number ) );
+			add_filter( 'wp_dropdown_cats', array( $this, 'modify_select' ) );
+			$dropdown_id    = ( $first_dropdown ) ? 'cat' : "{$this->id_base}-dropdown-{$this->number}";
+			$first_dropdown = false;
+			echo '<label class="screen-reader-text" for="' . esc_attr( $dropdown_id ) . '">' . esc_html( $title ) . '</label>';
+			$cat_args['show_option_none'] = __( 'Select Category', 'default' );
+			$cat_args['id']               = $dropdown_id;
+
+			/** This filter is documented in wp-includes/widgets/class-wp-widget-categories.php */
+			wp_dropdown_categories( apply_filters( 'widget_categories_dropdown_args', $cat_args, $instance ) );
+			remove_filter( 'wp_dropdown_cats', array( $this, 'modify_select' ) );
+			echo '</form>';
+		else :
+			?>
+			<ul>
+			<?php
+			$cat_args['title_li'] = '';
+
+			/** This filter is documented in wp-includes/widgets/class-wp-widget-categories.php */
+			wp_list_categories( apply_filters( 'widget_categories_args', $cat_args, $instance ) );
+			?>
+			</ul>
+		<?php
+		endif;
+		echo wp_kses_post( $args['after_widget'] );
+	}
+
+}

includes/widgets/class-amp-widget-recent-comments.php

@@ -0,0 +1,25 @@
+<?php
+/**
+ * Class AMP_Widget_Recent_Comments
+ *
+ * @package AMP
+ */
+
+/**
+ * Class AMP_Widget_Recent_Comments
+ *
+ * @package AMP
+ */
+class AMP_Widget_Recent_Comments extends WP_Widget_Recent_Comments {
+
+	/**
+	 * Instantiates the widget, and prevents inline styling.
+	 */
+	public function __construct() {
+		parent::__construct();
+		if ( is_amp_endpoint() ) {
+			add_filter( 'show_recent_comments_widget_style', '__return_false' );
+		}
+	}
+
+}

phpcs.xml

@@ -7,7 +7,7 @@
 
 	<rule ref="WordPress.WP.I18n">
 		<properties>
-			<property name="text_domain" value="amp" />
+			<property name="text_domain" value="amp,default" />
 		</properties>
 	</rule>
 

tests/test-class-amp-theme-support.php

@@ -68,6 +68,23 @@ public function test_is_paired_available() {
 		$this->assertFalse( AMP_Theme_Support::is_paired_available() );
 	}
 
+	/**
+	 * Test register_widgets().
+	 *
+	 * @covers AMP_Theme_Support::register_widgets()
+	 * @global WP_Widget_Factory $wp_widget_factory
+	 */
+	public function test_register_widgets() {
+		global $wp_widget_factory;
+		remove_all_actions( 'widgets_init' );
+		$wp_widget_factory->widgets = array();
+		wp_widgets_init();
+		AMP_Theme_Support::register_widgets();
+
+		$this->assertArrayNotHasKey( 'WP_Widget_Categories', $wp_widget_factory->widgets );
+		$this->assertArrayHasKey( 'AMP_Widget_Categories', $wp_widget_factory->widgets );
+	}
+
 	/**
 	 * Test finish_output_buffering.
 	 *