diff -r c7c34916027a -r 177826044cd9 wp/wp-includes/blocks/rss.php
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/wp/wp-includes/blocks/rss.php	Mon Oct 14 18:28:13 2019 +0200
@@ -0,0 +1,137 @@
+<?php
+/**
+ * Server-side rendering of the `core/rss` block.
+ *
+ * @package WordPress
+ */
+
+/**
+ * Renders the `core/rss` block on server.
+ *
+ * @param array $attributes The block attributes.
+ *
+ * @return string Returns the block content with received rss items.
+ */
+function render_block_core_rss( $attributes ) {
+	$rss = fetch_feed( $attributes['feedURL'] );
+
+	if ( is_wp_error( $rss ) ) {
+		return '<div class="components-placeholder"><div class="notice notice-error"><strong>' . __( 'RSS Error:' ) . '</strong> ' . $rss->get_error_message() . '</div></div>';
+	}
+
+	if ( ! $rss->get_item_quantity() ) {
+		// PHP 5.2 compatibility. See: http://simplepie.org/wiki/faq/i_m_getting_memory_leaks.
+		$rss->__destruct();
+		unset( $rss );
+
+		return '<div class="components-placeholder"><div class="notice notice-error">' . __( 'An error has occurred, which probably means the feed is down. Try again later.' ) . '</div></div>';
+	}
+
+	$rss_items  = $rss->get_items( 0, $attributes['itemsToShow'] );
+	$list_items = '';
+	foreach ( $rss_items as $item ) {
+		$title = esc_html( trim( strip_tags( $item->get_title() ) ) );
+		if ( empty( $title ) ) {
+			$title = __( '(Untitled)' );
+		}
+		$link = $item->get_link();
+		$link = esc_url( $link );
+		if ( $link ) {
+			$title = "<a href='{$link}'>{$title}</a>";
+		}
+		$title = "<div class='wp-block-rss__item-title'>{$title}</div>";
+
+		$date = '';
+		if ( $attributes['displayDate'] ) {
+			$date = $item->get_date( 'U' );
+
+			if ( $date ) {
+				$date = sprintf(
+					'<time datetime="%1$s" class="wp-block-rss__item-publish-date">%2$s</time> ',
+					date_i18n( get_option( 'c' ), $date ),
+					date_i18n( get_option( 'date_format' ), $date )
+				);
+			}
+		}
+
+		$author = '';
+		if ( $attributes['displayAuthor'] ) {
+			$author = $item->get_author();
+			if ( is_object( $author ) ) {
+				$author = $author->get_name();
+				$author = '<span class="wp-block-rss__item-author">' . __( 'by' ) . ' ' . esc_html( strip_tags( $author ) ) . '</span>';
+			}
+		}
+
+		$excerpt = '';
+		if ( $attributes['displayExcerpt'] ) {
+			$excerpt = html_entity_decode( $item->get_description(), ENT_QUOTES, get_option( 'blog_charset' ) );
+			$excerpt = esc_attr( wp_trim_words( $excerpt, $attributes['excerptLength'], ' [&hellip;]' ) );
+
+			// Change existing [...] to [&hellip;].
+			if ( '[...]' == substr( $excerpt, -5 ) ) {
+				$excerpt = substr( $excerpt, 0, -5 ) . '[&hellip;]';
+			}
+
+			$excerpt = '<div class="wp-block-rss__item-excerpt">' . esc_html( $excerpt ) . '</div>';
+		}
+
+		$list_items .= "<li class='wp-block-rss__item'>{$title}{$date}{$author}{$excerpt}</li>";
+	}
+
+	$classes           = 'grid' === $attributes['blockLayout'] ? ' is-grid columns-' . $attributes['columns'] : '';
+	$list_items_markup = "<ul class='wp-block-rss{$classes}'>{$list_items}</ul>";
+
+	// PHP 5.2 compatibility. See: http://simplepie.org/wiki/faq/i_m_getting_memory_leaks.
+	$rss->__destruct();
+	unset( $rss );
+
+	return $list_items_markup;
+}
+
+/**
+ * Registers the `core/rss` block on server.
+ */
+function register_block_core_rss() {
+	register_block_type( 'core/rss',
+		array(
+			'attributes'      => array(
+				'columns'        => array(
+					'type'    => 'number',
+					'default' => 2,
+				),
+				'blockLayout'    => array(
+					'type'    => 'string',
+					'default' => 'list',
+				),
+				'feedURL'        => array(
+					'type'    => 'string',
+					'default' => '',
+				),
+				'itemsToShow'    => array(
+					'type'    => 'number',
+					'default' => 5,
+				),
+				'displayExcerpt' => array(
+					'type'    => 'boolean',
+					'default' => false,
+				),
+				'displayAuthor'  => array(
+					'type'    => 'boolean',
+					'default' => false,
+				),
+				'displayDate'    => array(
+					'type'    => 'boolean',
+					'default' => false,
+				),
+				'excerptLength'  => array(
+					'type'    => 'number',
+					'default' => 55,
+				),
+			),
+			'render_callback' => 'render_block_core_rss',
+		)
+	);
+}
+
+add_action( 'init', 'register_block_core_rss' );