diff -r 7b1b88e27a20 -r 48c4eec2b7e6 wp/wp-includes/class-wp-block-bindings-registry.php
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/wp/wp-includes/class-wp-block-bindings-registry.php	Fri Sep 05 18:40:08 2025 +0200
@@ -0,0 +1,308 @@
+<?php
+/**
+ * Block Bindings API: WP_Block_Bindings_Registry class.
+ *
+ * Supports overriding content in blocks by connecting them to different sources.
+ *
+ * @package WordPress
+ * @subpackage Block Bindings
+ * @since 6.5.0
+ */
+
+/**
+ * Core class used for interacting with block bindings sources.
+ *
+ * @since 6.5.0
+ */
+final class WP_Block_Bindings_Registry {
+
+	/**
+	 * Holds the registered block bindings sources, keyed by source identifier.
+	 *
+	 * @since 6.5.0
+	 * @var WP_Block_Bindings_Source[]
+	 */
+	private $sources = array();
+
+	/**
+	 * Container for the main instance of the class.
+	 *
+	 * @since 6.5.0
+	 * @var WP_Block_Bindings_Registry|null
+	 */
+	private static $instance = null;
+
+	/**
+	 * Supported source properties that can be passed to the registered source.
+	 *
+	 * @since 6.5.0
+	 * @var string[]
+	 */
+	private $allowed_source_properties = array(
+		'label',
+		'get_value_callback',
+		'uses_context',
+	);
+
+	/**
+	 * Supported blocks that can use the block bindings API.
+	 *
+	 * @since 6.5.0
+	 * @var string[]
+	 */
+	private $supported_blocks = array(
+		'core/paragraph',
+		'core/heading',
+		'core/image',
+		'core/button',
+	);
+
+	/**
+	 * Registers a new block bindings source.
+	 *
+	 * This is a low-level method. For most use cases, it is recommended to use
+	 * the `register_block_bindings_source()` function instead.
+	 *
+	 * @see register_block_bindings_source()
+	 *
+	 * Sources are used to override block's original attributes with a value
+	 * coming from the source. Once a source is registered, it can be used by a
+	 * block by setting its `metadata.bindings` attribute to a value that refers
+	 * to the source.
+	 *
+	 * @since 6.5.0
+	 *
+	 * @param string $source_name       The name of the source. It must be a string containing a namespace prefix, i.e.
+	 *                                  `my-plugin/my-custom-source`. It must only contain lowercase alphanumeric
+	 *                                  characters, the forward slash `/` and dashes.
+	 * @param array  $source_properties {
+	 *     The array of arguments that are used to register a source.
+	 *
+	 *     @type string   $label              The label of the source.
+	 *     @type callable $get_value_callback A callback executed when the source is processed during block rendering.
+	 *                                        The callback should have the following signature:
+	 *
+	 *                                        `function( $source_args, $block_instance, $attribute_name ): mixed`
+	 *                                            - @param array    $source_args    Array containing source arguments
+	 *                                                                              used to look up the override value,
+	 *                                                                              i.e. {"key": "foo"}.
+	 *                                            - @param WP_Block $block_instance The block instance.
+	 *                                            - @param string   $attribute_name The name of the target attribute.
+	 *                                        The callback has a mixed return type; it may return a string to override
+	 *                                        the block's original value, null, false to remove an attribute, etc.
+	 *     @type string[] $uses_context       Optional. Array of values to add to block `uses_context` needed by the source.
+	 * }
+	 * @return WP_Block_Bindings_Source|false Source when the registration was successful, or `false` on failure.
+	 */
+	public function register( string $source_name, array $source_properties ) {
+		if ( ! is_string( $source_name ) ) {
+			_doing_it_wrong(
+				__METHOD__,
+				__( 'Block bindings source name must be a string.' ),
+				'6.5.0'
+			);
+			return false;
+		}
+
+		if ( preg_match( '/[A-Z]+/', $source_name ) ) {
+			_doing_it_wrong(
+				__METHOD__,
+				__( 'Block bindings source names must not contain uppercase characters.' ),
+				'6.5.0'
+			);
+			return false;
+		}
+
+		$name_matcher = '/^[a-z0-9-]+\/[a-z0-9-]+$/';
+		if ( ! preg_match( $name_matcher, $source_name ) ) {
+			_doing_it_wrong(
+				__METHOD__,
+				__( 'Block bindings source names must contain a namespace prefix. Example: my-plugin/my-custom-source' ),
+				'6.5.0'
+			);
+			return false;
+		}
+
+		if ( $this->is_registered( $source_name ) ) {
+			_doing_it_wrong(
+				__METHOD__,
+				/* translators: %s: Block bindings source name. */
+				sprintf( __( 'Block bindings source "%s" already registered.' ), $source_name ),
+				'6.5.0'
+			);
+			return false;
+		}
+
+		// Validates that the source properties contain the label.
+		if ( ! isset( $source_properties['label'] ) ) {
+			_doing_it_wrong(
+				__METHOD__,
+				__( 'The $source_properties must contain a "label".' ),
+				'6.5.0'
+			);
+			return false;
+		}
+
+		// Validates that the source properties contain the get_value_callback.
+		if ( ! isset( $source_properties['get_value_callback'] ) ) {
+			_doing_it_wrong(
+				__METHOD__,
+				__( 'The $source_properties must contain a "get_value_callback".' ),
+				'6.5.0'
+			);
+			return false;
+		}
+
+		// Validates that the get_value_callback is a valid callback.
+		if ( ! is_callable( $source_properties['get_value_callback'] ) ) {
+			_doing_it_wrong(
+				__METHOD__,
+				__( 'The "get_value_callback" parameter must be a valid callback.' ),
+				'6.5.0'
+			);
+			return false;
+		}
+
+		// Validates that the uses_context parameter is an array.
+		if ( isset( $source_properties['uses_context'] ) && ! is_array( $source_properties['uses_context'] ) ) {
+			_doing_it_wrong(
+				__METHOD__,
+				__( 'The "uses_context" parameter must be an array.' ),
+				'6.5.0'
+			);
+			return false;
+		}
+
+		if ( ! empty( array_diff( array_keys( $source_properties ), $this->allowed_source_properties ) ) ) {
+			_doing_it_wrong(
+				__METHOD__,
+				__( 'The $source_properties array contains invalid properties.' ),
+				'6.5.0'
+			);
+			return false;
+		}
+
+		$source = new WP_Block_Bindings_Source(
+			$source_name,
+			$source_properties
+		);
+
+		$this->sources[ $source_name ] = $source;
+
+		// Adds `uses_context` defined by block bindings sources.
+		add_filter(
+			'get_block_type_uses_context',
+			function ( $uses_context, $block_type ) use ( $source ) {
+				if ( ! in_array( $block_type->name, $this->supported_blocks, true ) || empty( $source->uses_context ) ) {
+					return $uses_context;
+				}
+				// Use array_values to reset the array keys.
+				return array_values( array_unique( array_merge( $uses_context, $source->uses_context ) ) );
+			},
+			10,
+			2
+		);
+
+		return $source;
+	}
+
+	/**
+	 * Unregisters a block bindings source.
+	 *
+	 * @since 6.5.0
+	 *
+	 * @param string $source_name Block bindings source name including namespace.
+	 * @return WP_Block_Bindings_Source|false The unregistered block bindings source on success and `false` otherwise.
+	 */
+	public function unregister( string $source_name ) {
+		if ( ! $this->is_registered( $source_name ) ) {
+			_doing_it_wrong(
+				__METHOD__,
+				/* translators: %s: Block bindings source name. */
+				sprintf( __( 'Block binding "%s" not found.' ), $source_name ),
+				'6.5.0'
+			);
+			return false;
+		}
+
+		$unregistered_source = $this->sources[ $source_name ];
+		unset( $this->sources[ $source_name ] );
+
+		return $unregistered_source;
+	}
+
+	/**
+	 * Retrieves the list of all registered block bindings sources.
+	 *
+	 * @since 6.5.0
+	 *
+	 * @return WP_Block_Bindings_Source[] The array of registered sources.
+	 */
+	public function get_all_registered() {
+		return $this->sources;
+	}
+
+	/**
+	 * Retrieves a registered block bindings source.
+	 *
+	 * @since 6.5.0
+	 *
+	 * @param string $source_name The name of the source.
+	 * @return WP_Block_Bindings_Source|null The registered block bindings source, or `null` if it is not registered.
+	 */
+	public function get_registered( string $source_name ) {
+		if ( ! $this->is_registered( $source_name ) ) {
+			return null;
+		}
+
+		return $this->sources[ $source_name ];
+	}
+
+	/**
+	 * Checks if a block bindings source is registered.
+	 *
+	 * @since 6.5.0
+	 *
+	 * @param string $source_name The name of the source.
+	 * @return bool `true` if the block bindings source is registered, `false` otherwise.
+	 */
+	public function is_registered( $source_name ) {
+		return isset( $this->sources[ $source_name ] );
+	}
+
+	/**
+	 * Wakeup magic method.
+	 *
+	 * @since 6.5.0
+	 */
+	public function __wakeup() {
+		if ( ! $this->sources ) {
+			return;
+		}
+		if ( ! is_array( $this->sources ) ) {
+			throw new UnexpectedValueException();
+		}
+		foreach ( $this->sources as $value ) {
+			if ( ! $value instanceof WP_Block_Bindings_Source ) {
+				throw new UnexpectedValueException();
+			}
+		}
+	}
+
+	/**
+	 * Utility method to retrieve the main instance of the class.
+	 *
+	 * The instance will be created if it does not exist yet.
+	 *
+	 * @since 6.5.0
+	 *
+	 * @return WP_Block_Bindings_Registry The main instance.
+	 */
+	public static function get_instance() {
+		if ( null === self::$instance ) {
+			self::$instance = new self();
+		}
+
+		return self::$instance;
+	}
+}