first commit

wp-includes/blocks/paragraph.php

@@ -0,0 +1,48 @@
+<?php
+/**
+ * Server-side rendering of the `core/paragraph` block.
+ *
+ * @package WordPress
+ */
+
+/**
+ * Append the `wp-block-paragraph` class before rendering the stored
+ * `core/paragraph` block contents.
+ *
+ * For example, the following block content:
+ *  <p class="align-left">Hello World</p>
+ *
+ * Would be transformed to:
+ *  <p class="align-left wp-block-paragraph">Hello World</p>
+ *
+ * @since 7.0.0
+ *
+ * @param string $block_content The block content.
+ *
+ * @return string Filtered block content.
+ */
+function block_core_paragraph_add_class( $block_content ) {
+	if ( ! $block_content ) {
+		return $block_content;
+	}
+
+	$processor = new WP_HTML_Tag_Processor( $block_content );
+
+	if ( $processor->next_tag( 'p' ) ) {
+		$processor->add_class( 'wp-block-paragraph' );
+	}
+
+	return $processor->get_updated_html();
+}
+
+add_filter( 'render_block_core/paragraph', 'block_core_paragraph_add_class' );
+
+/**
+ * Registers the `core/paragraph` block on server.
+ *
+ * @since 7.0.0
+ */
+function register_block_core_paragraph() {
+	register_block_type_from_metadata( __DIR__ . '/paragraph' );
+}
+add_action( 'init', 'register_block_core_paragraph' );