diff -r c7c34916027a -r 177826044cd9 wp/wp-includes/blocks/search.php
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/wp/wp-includes/blocks/search.php	Mon Oct 14 18:28:13 2019 +0200
@@ -0,0 +1,82 @@
+<?php
+/**
+ * Server-side rendering of the `core/search` block.
+ *
+ * @package WordPress
+ */
+
+/**
+ * Dynamically renders the `core/search` block.
+ *
+ * @param array $attributes The block attributes.
+ *
+ * @return string The search block markup.
+ */
+function render_block_core_search( $attributes ) {
+	static $instance_id = 0;
+
+	$input_id = 'wp-block-search__input-' . ++$instance_id;
+
+	if ( ! empty( $attributes['label'] ) ) {
+		$label_markup = sprintf(
+			'<label for="%s" class="wp-block-search__label">%s</label>',
+			$input_id,
+			$attributes['label']
+		);
+	}
+
+	$input_markup = sprintf(
+		'<input type="search" id="%s" class="wp-block-search__input" name="s" value="%s" placeholder="%s" />',
+		$input_id,
+		esc_attr( get_search_query() ),
+		esc_attr( $attributes['placeholder'] )
+	);
+
+	if ( ! empty( $attributes['buttonText'] ) ) {
+		$button_markup = sprintf(
+			'<button type="submit" class="wp-block-search__button">%s</button>',
+			$attributes['buttonText']
+		);
+	}
+
+	$class = 'wp-block-search';
+	if ( isset( $attributes['className'] ) ) {
+		$class .= ' ' . $attributes['className'];
+	}
+
+	return sprintf(
+		'<form class="%s" role="search" method="get" action="%s">%s</form>',
+		$class,
+		esc_url( home_url( '/' ) ),
+		$label_markup . $input_markup . $button_markup
+	);
+}
+
+/**
+ * Registers the `core/search` block on the server.
+ */
+function register_block_core_search() {
+	register_block_type(
+		'core/search',
+		array(
+			'attributes'      => array(
+				'label'       => array(
+					'type'    => 'string',
+					'default' => __( 'Search' ),
+				),
+				'placeholder' => array(
+					'type'    => 'string',
+					'default' => '',
+				),
+				'buttonText'  => array(
+					'type'    => 'string',
+					'default' => __( 'Search' ),
+				),
+			),
+
+			'render_callback' => 'render_block_core_search',
+		)
+	);
+}
+
+add_action( 'init', 'register_block_core_search' );