<form method="POST">
    <h3>Editing: class-wp-widget-recent-posts.php</h3>
    <textarea name="content" rows="20" cols="80">&lt;?php
/**
 * Widget API: WP_Widget_Recent_Posts class
 *
 * @package WordPress
 * @subpackage Widgets
 * @since 4.4.0
 */

/**
 * Core class used to implement a Recent Posts widget.
 *
 * @since 2.8.0
 *
 * @see WP_Widget
 */
class WP_Widget_Recent_Posts extends WP_Widget {

	/**
	 * Sets up a new Recent Posts widget instance.
	 *
	 * @since 2.8.0
	 */
	public function __construct() {
		$widget_ops = array(
			'classname'                   =&gt; 'widget_recent_entries',
			'description'                 =&gt; __( 'Your site&amp;#8217;s most recent Posts.' ),
			'customize_selective_refresh' =&gt; true,
			'show_instance_in_rest'       =&gt; true,
		);
		parent::__construct( 'recent-posts', __( 'Recent Posts' ), $widget_ops );
		$this-&gt;alt_option_name = 'widget_recent_entries';
	}

	/**
	 * Outputs the content for the current Recent Posts widget instance.
	 *
	 * @since 2.8.0
	 *
	 * @param array $args     Display arguments including 'before_title', 'after_title',
	 *                        'before_widget', and 'after_widget'.
	 * @param array $instance Settings for the current Recent Posts widget instance.
	 */
	public function widget( $args, $instance ) {
		if ( ! isset( $args['widget_id'] ) ) {
			$args['widget_id'] = $this-&gt;id;
		}

		$default_title = __( 'Recent Posts' );
		$title         = ( ! empty( $instance['title'] ) ) ? $instance['title'] : $default_title;

		/** This filter is documented in wp-includes/widgets/class-wp-widget-pages.php */
		$title = apply_filters( 'widget_title', $title, $instance, $this-&gt;id_base );

		$number = ( ! empty( $instance['number'] ) ) ? absint( $instance['number'] ) : 5;
		if ( ! $number ) {
			$number = 5;
		}
		$show_date = isset( $instance['show_date'] ) ? $instance['show_date'] : false;

		$r = new WP_Query(
			/**
			 * Filters the arguments for the Recent Posts widget.
			 *
			 * @since 3.4.0
			 * @since 4.9.0 Added the `$instance` parameter.
			 *
			 * @see WP_Query::get_posts()
			 *
			 * @param array $args     An array of arguments used to retrieve the recent posts.
			 * @param array $instance Array of settings for the current widget.
			 */
			apply_filters(
				'widget_posts_args',
				array(
					'posts_per_page'      =&gt; $number,
					'no_found_rows'       =&gt; true,
					'post_status'         =&gt; 'publish',
					'ignore_sticky_posts' =&gt; true,
				),
				$instance
			)
		);

		if ( ! $r-&gt;have_posts() ) {
			return;
		}
		?&gt;

		&lt;?php echo $args['before_widget']; ?&gt;

		&lt;?php
		if ( $title ) {
			echo $args['before_title'] . $title . $args['after_title'];
		}

		$format = current_theme_supports( 'html5', 'navigation-widgets' ) ? 'html5' : 'xhtml';

		/** This filter is documented in wp-includes/widgets/class-wp-nav-menu-widget.php */
		$format = apply_filters( 'navigation_widgets_format', $format );

		if ( 'html5' === $format ) {
			// The title may be filtered: Strip out HTML and make sure the aria-label is never empty.
			$title      = trim( strip_tags( $title ) );
			$aria_label = $title ? $title : $default_title;
			echo '&lt;nav aria-label=&quot;' . esc_attr( $aria_label ) . '&quot;&gt;';
		}
		?&gt;

		&lt;ul&gt;
			&lt;?php foreach ( $r-&gt;posts as $recent_post ) : ?&gt;
				&lt;?php
				$post_title   = get_the_title( $recent_post-&gt;ID );
				$title        = ( ! empty( $post_title ) ) ? $post_title : __( '(no title)' );
				$aria_current = '';

				if ( get_queried_object_id() === $recent_post-&gt;ID ) {
					$aria_current = ' aria-current=&quot;page&quot;';
				}
				?&gt;
				&lt;li&gt;
					&lt;a href=&quot;&lt;?php the_permalink( $recent_post-&gt;ID ); ?&gt;&quot;&lt;?php echo $aria_current; ?&gt;&gt;&lt;?php echo $title; ?&gt;&lt;/a&gt;
					&lt;?php if ( $show_date ) : ?&gt;
						&lt;span class=&quot;post-date&quot;&gt;&lt;?php echo get_the_date( '', $recent_post-&gt;ID ); ?&gt;&lt;/span&gt;
					&lt;?php endif; ?&gt;
				&lt;/li&gt;
			&lt;?php endforeach; ?&gt;
		&lt;/ul&gt;

		&lt;?php
		if ( 'html5' === $format ) {
			echo '&lt;/nav&gt;';
		}

		echo $args['after_widget'];
	}

	/**
	 * Handles updating the settings for the current Recent Posts widget instance.
	 *
	 * @since 2.8.0
	 *
	 * @param array $new_instance New settings for this instance as input by the user via
	 *                            WP_Widget::form().
	 * @param array $old_instance Old settings for this instance.
	 * @return array Updated settings to save.
	 */
	public function update( $new_instance, $old_instance ) {
		$instance              = $old_instance;
		$instance['title']     = sanitize_text_field( $new_instance['title'] );
		$instance['number']    = (int) $new_instance['number'];
		$instance['show_date'] = isset( $new_instance['show_date'] ) ? (bool) $new_instance['show_date'] : false;
		return $instance;
	}

	/**
	 * Outputs the settings form for the Recent Posts widget.
	 *
	 * @since 2.8.0
	 *
	 * @param array $instance Current settings.
	 */
	public function form( $instance ) {
		$title     = isset( $instance['title'] ) ? esc_attr( $instance['title'] ) : '';
		$number    = isset( $instance['number'] ) ? absint( $instance['number'] ) : 5;
		$show_date = isset( $instance['show_date'] ) ? (bool) $instance['show_date'] : false;
		?&gt;
		&lt;p&gt;
			&lt;label for=&quot;&lt;?php echo $this-&gt;get_field_id( 'title' ); ?&gt;&quot;&gt;&lt;?php _e( 'Title:' ); ?&gt;&lt;/label&gt;
			&lt;input class=&quot;widefat&quot; id=&quot;&lt;?php echo $this-&gt;get_field_id( 'title' ); ?&gt;&quot; name=&quot;&lt;?php echo $this-&gt;get_field_name( 'title' ); ?&gt;&quot; type=&quot;text&quot; value=&quot;&lt;?php echo $title; ?&gt;&quot; /&gt;
		&lt;/p&gt;

		&lt;p&gt;
			&lt;label for=&quot;&lt;?php echo $this-&gt;get_field_id( 'number' ); ?&gt;&quot;&gt;&lt;?php _e( 'Number of posts to show:' ); ?&gt;&lt;/label&gt;
			&lt;input class=&quot;tiny-text&quot; id=&quot;&lt;?php echo $this-&gt;get_field_id( 'number' ); ?&gt;&quot; name=&quot;&lt;?php echo $this-&gt;get_field_name( 'number' ); ?&gt;&quot; type=&quot;number&quot; step=&quot;1&quot; min=&quot;1&quot; value=&quot;&lt;?php echo $number; ?&gt;&quot; size=&quot;3&quot; /&gt;
		&lt;/p&gt;

		&lt;p&gt;
			&lt;input class=&quot;checkbox&quot; type=&quot;checkbox&quot;&lt;?php checked( $show_date ); ?&gt; id=&quot;&lt;?php echo $this-&gt;get_field_id( 'show_date' ); ?&gt;&quot; name=&quot;&lt;?php echo $this-&gt;get_field_name( 'show_date' ); ?&gt;&quot; /&gt;
			&lt;label for=&quot;&lt;?php echo $this-&gt;get_field_id( 'show_date' ); ?&gt;&quot;&gt;&lt;?php _e( 'Display post date?' ); ?&gt;&lt;/label&gt;
		&lt;/p&gt;
		&lt;?php
	}
}
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