Allow PHP-Only Block Registration

src/wp-includes/block-supports/auto-register.php

@@ -0,0 +1,61 @@
+<?php
+/**
+ * Auto-register block support.
+ *
+ * @package WordPress
+ * @since 7.0.0
+ */
+
+/**
+ * Marks user-defined attributes for auto-generated inspector controls.
+ *
+ * This filter runs during block type registration, before the WP_Block_Type
+ * is instantiated. Block supports add their attributes AFTER the block type
+ * is created (via {@see WP_Block_Supports::register_attributes()}), so any attributes
+ * present at this stage are user-defined.
+ *
+ * The marker tells generateFieldsFromAttributes() which attributes should
+ * get auto-generated inspector controls. Attributes are excluded if they:
+ * - Have a 'source' (HTML-derived, edited inline not via inspector)
+ * - Have role 'local' (internal state, not user-configurable)
+ * - Have an unsupported type (only 'string', 'number', 'integer', 'boolean' are supported)
+ * - Were added by block supports (added after this filter runs)
+ *
+ * @since 7.0.0
+ * @access private
+ *
+ * @param array<string, mixed> $args Array of arguments for registering a block type.
+ * @return array<string, mixed> Modified block type arguments.
+ */
+function wp_mark_auto_generate_control_attributes( array $args ): array {
+	if ( empty( $args['attributes'] ) || ! is_array( $args['attributes'] ) ) {
+		return $args;
+	}
+
+	$has_auto_register = ! empty( $args['supports']['autoRegister'] );
+	if ( ! $has_auto_register ) {
+		return $args;
+	}
+
+	foreach ( $args['attributes'] as $attr_key => $attr_schema ) {
+		// Skip HTML-derived attributes (edited inline, not via inspector).
+		if ( ! empty( $attr_schema['source'] ) ) {
+			continue;
+		}
+		// Skip internal attributes (not user-configurable).
+		if ( isset( $attr_schema['role'] ) && 'local' === $attr_schema['role'] ) {
+			continue;
+		}
+		// Skip unsupported types (only 'string', 'number', 'integer', 'boolean' are supported).
+		$type = $attr_schema['type'] ?? null;
+		if ( ! in_array( $type, array( 'string', 'number', 'integer', 'boolean' ), true ) ) {
+			continue;
+		}
+		$args['attributes'][ $attr_key ]['autoGenerateControl'] = true;
+	}
+
+	return $args;
+}
+
+// Priority 5 to mark original attributes before other filters (priority 10+) might add their own.
+add_filter( 'register_block_type_args', 'wp_mark_auto_generate_control_attributes', 5 );

src/wp-includes/blocks.php

@@ -3131,3 +3131,31 @@ function _wp_footnotes_force_filtered_html_on_import_filter( $arg ) {
 	}
 	return $arg;
 }
+
+/**
+ * Exposes blocks with autoRegister flag for ServerSideRender in the editor.
+ *
+ * Detects blocks that have the autoRegister flag set in their supports
+ * and passes them to JavaScript for auto-registration with ServerSideRender.
+ *
+ * @access private
+ * @since 7.0.0
+ */
+function _wp_enqueue_auto_register_blocks() {
+	$auto_register_blocks = array();
+	$registered_blocks    = WP_Block_Type_Registry::get_instance()->get_all_registered();
+
+	foreach ( $registered_blocks as $block_name => $block_type ) {
+		if ( ! empty( $block_type->supports['autoRegister'] ) && ! empty( $block_type->render_callback ) ) {
+			$auto_register_blocks[] = $block_name;
+		}
+	}
+
+	if ( ! empty( $auto_register_blocks ) ) {
+		wp_add_inline_script(
+			'wp-block-library',
+			sprintf( 'window.__unstableAutoRegisterBlocks = %s;', wp_json_encode( $auto_register_blocks ) ),
+			'before'
+		);
+	}
+}

src/wp-includes/default-filters.php

@@ -623,6 +623,7 @@
 add_action( 'enqueue_block_editor_assets', 'wp_enqueue_editor_format_library_assets' );
 add_action( 'enqueue_block_editor_assets', 'wp_enqueue_block_editor_script_modules' );
 add_action( 'enqueue_block_editor_assets', 'wp_enqueue_global_styles_css_custom_properties' );
+add_action( 'enqueue_block_editor_assets', '_wp_enqueue_auto_register_blocks' );
 add_action( 'wp_print_scripts', 'wp_just_in_time_script_localization' );
 add_filter( 'print_scripts_array', 'wp_prototype_before_jquery' );
 add_action( 'customize_controls_print_styles', 'wp_resource_hints', 1 );

src/wp-settings.php

@@ -394,6 +394,7 @@
 require ABSPATH . WPINC . '/class-wp-block-supports.php';
 require ABSPATH . WPINC . '/block-supports/utils.php';
 require ABSPATH . WPINC . '/block-supports/align.php';
+require ABSPATH . WPINC . '/block-supports/auto-register.php';
 require ABSPATH . WPINC . '/block-supports/custom-classname.php';
 require ABSPATH . WPINC . '/block-supports/generated-classname.php';
 require ABSPATH . WPINC . '/block-supports/settings.php';

tests/phpunit/tests/block-supports/auto-register.php

@@ -0,0 +1,144 @@
+<?php
+/**
+ * @group block-supports
+ *
+ * @covers ::wp_mark_auto_generate_control_attributes
+ */
+class Tests_Block_Supports_Auto_Register extends WP_UnitTestCase {
+
+	/**
+	 * Tests that attributes are marked when autoRegister is enabled.
+	 *
+	 * @ticket 64639
+	 */
+	public function test_marks_attributes_with_auto_register_flag() {
+		$settings = array(
+			'supports'   => array( 'autoRegister' => true ),
+			'attributes' => array(
+				'title' => array( 'type' => 'string' ),
+				'count' => array( 'type' => 'integer' ),
+			),
+		);
+
+		$result = wp_mark_auto_generate_control_attributes( $settings );
+
+		$this->assertTrue( $result['attributes']['title']['autoGenerateControl'] );
+		$this->assertTrue( $result['attributes']['count']['autoGenerateControl'] );
+	}
+
+	/**
+	 * Tests that attributes are not marked without autoRegister flag.
+	 *
+	 * @ticket 64639
+	 */
+	public function test_does_not_mark_attributes_without_auto_register() {
+		$settings = array(
+			'attributes' => array(
+				'title' => array( 'type' => 'string' ),
+			),
+		);
+
+		$result = wp_mark_auto_generate_control_attributes( $settings );
+
+		$this->assertArrayNotHasKey( 'autoGenerateControl', $result['attributes']['title'] );
+	}
+
+	/**
+	 * Tests that attributes with source are excluded.
+	 *
+	 * @ticket 64639
+	 */
+	public function test_excludes_attributes_with_source() {
+		$settings = array(
+			'supports'   => array( 'autoRegister' => true ),
+			'attributes' => array(
+				'title'   => array( 'type' => 'string' ),
+				'content' => array(
+					'type'   => 'string',
+					'source' => 'html',
+				),
+			),
+		);
+
+		$result = wp_mark_auto_generate_control_attributes( $settings );
+
+		$this->assertTrue( $result['attributes']['title']['autoGenerateControl'] );
+		$this->assertArrayNotHasKey( 'autoGenerateControl', $result['attributes']['content'] );
+	}
+
+	/**
+	 * Tests that attributes with role: local are excluded.
+	 *
+	 * Example: The 'blob' attribute in media blocks (image, video, file, audio)
+	 * stores a temporary blob URL during file upload. This is internal state
+	 * that shouldn't be shown in the inspector or saved to the database.
+	 *
+	 * @ticket 64639
+	 */
+	public function test_excludes_attributes_with_role_local() {
+		$settings = array(
+			'supports'   => array( 'autoRegister' => true ),
+			'attributes' => array(
+				'title' => array( 'type' => 'string' ),
+				'blob'  => array(
+					'type' => 'string',
+					'role' => 'local',
+				),
+			),
+		);
+
+		$result = wp_mark_auto_generate_control_attributes( $settings );
+
+		$this->assertTrue( $result['attributes']['title']['autoGenerateControl'] );
+		$this->assertArrayNotHasKey( 'autoGenerateControl', $result['attributes']['blob'] );
+	}
+
+	/**
+	 * Tests that empty attributes are handled gracefully.
+	 *
+	 * @ticket 64639
+	 */
+	public function test_handles_empty_attributes() {
+		$settings = array(
+			'supports' => array( 'autoRegister' => true ),
+		);
+
+		$result = wp_mark_auto_generate_control_attributes( $settings );
+
+		$this->assertSame( $settings, $result );
+	}
+
+	/**
+	 * Tests that only allowed attributes are marked.
+	 *
+	 * @ticket 64639
+	 */
+	public function test_excludes_unsupported_types() {
+		$settings = array(
+			'supports'   => array( 'autoRegister' => true ),
+			'attributes' => array(
+				// Supported types
+				'text'     => array( 'type' => 'string' ),
+				'price'    => array( 'type' => 'number' ),
+				'count'    => array( 'type' => 'integer' ),
+				'enabled'  => array( 'type' => 'boolean' ),
+				// Unsupported types
+				'metadata' => array( 'type' => 'object' ),
+				'items'    => array( 'type' => 'array' ),
+				'config'   => array( 'type' => 'null' ),
+				'unknown'  => array( 'type' => 'unknown' ),
+			),
+		);
+
+		$result = wp_mark_auto_generate_control_attributes( $settings );
+
+		$this->assertTrue( $result['attributes']['text']['autoGenerateControl'] );
+		$this->assertTrue( $result['attributes']['price']['autoGenerateControl'] );
+		$this->assertTrue( $result['attributes']['count']['autoGenerateControl'] );
+		$this->assertTrue( $result['attributes']['enabled']['autoGenerateControl'] );
+		$this->assertArrayNotHasKey( 'autoGenerateControl', $result['attributes']['metadata'] );
+		$this->assertArrayNotHasKey( 'autoGenerateControl', $result['attributes']['items'] );
+		$this->assertArrayNotHasKey( 'autoGenerateControl', $result['attributes']['config'] );
+		$this->assertArrayNotHasKey( 'autoGenerateControl', $result['attributes']['unknown'] );
+	}
+}