diff -r 34716fd837a4 -r be944660c56a wp/wp-includes/blocks/post-excerpt.php
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/wp/wp-includes/blocks/post-excerpt.php	Wed Sep 21 18:19:35 2022 +0200
@@ -0,0 +1,63 @@
+<?php
+/**
+ * Server-side rendering of the `core/post-excerpt` block.
+ *
+ * @package WordPress
+ */
+
+/**
+ * Renders the `core/post-excerpt` block on the server.
+ *
+ * @param array    $attributes Block attributes.
+ * @param string   $content    Block default content.
+ * @param WP_Block $block      Block instance.
+ * @return string Returns the filtered post excerpt for the current post wrapped inside "p" tags.
+ */
+function render_block_core_post_excerpt( $attributes, $content, $block ) {
+	if ( ! isset( $block->context['postId'] ) ) {
+		return '';
+	}
+
+	$more_text           = ! empty( $attributes['moreText'] ) ? '<a class="wp-block-post-excerpt__more-link" href="' . esc_url( get_the_permalink( $block->context['postId'] ) ) . '">' . $attributes['moreText'] . '</a>' : '';
+	$filter_excerpt_more = function( $more ) use ( $more_text ) {
+		return empty( $more_text ) ? $more : '';
+	};
+	/**
+	 * Some themes might use `excerpt_more` filter to handle the
+	 * `more` link displayed after a trimmed excerpt. Since the
+	 * block has a `more text` attribute we have to check and
+	 * override if needed the return value from this filter.
+	 * So if the block's attribute is not empty override the
+	 * `excerpt_more` filter and return nothing. This will
+	 * result in showing only one `read more` link at a time.
+	 */
+	add_filter( 'excerpt_more', $filter_excerpt_more );
+	$classes = '';
+	if ( isset( $attributes['textAlign'] ) ) {
+		$classes .= "has-text-align-{$attributes['textAlign']}";
+	}
+	$wrapper_attributes = get_block_wrapper_attributes( array( 'class' => $classes ) );
+
+	$content               = '<p class="wp-block-post-excerpt__excerpt">' . get_the_excerpt( $block->context['postId'] );
+	$show_more_on_new_line = ! isset( $attributes['showMoreOnNewLine'] ) || $attributes['showMoreOnNewLine'];
+	if ( $show_more_on_new_line && ! empty( $more_text ) ) {
+		$content .= '</p><p class="wp-block-post-excerpt__more-text">' . $more_text . '</p>';
+	} else {
+		$content .= " $more_text</p>";
+	}
+	remove_filter( 'excerpt_more', $filter_excerpt_more );
+	return sprintf( '<div %1$s>%2$s</div>', $wrapper_attributes, $content );
+}
+
+/**
+ * Registers the `core/post-excerpt` block on the server.
+ */
+function register_block_core_post_excerpt() {
+	register_block_type_from_metadata(
+		__DIR__ . '/post-excerpt',
+		array(
+			'render_callback' => 'render_block_core_post_excerpt',
+		)
+	);
+}
+add_action( 'init', 'register_block_core_post_excerpt' );