Editor: Introduce WP_Block_Bindings_Source class

Abstracts the block bindings source array into a well-defined object.

Fixes #60447.
See #60282.
Follow-up [57373].
Props czapla, santosguillamot, gziolo.



git-svn-id: https://develop.svn.wordpress.org/trunk@57562 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/class-wp-block-bindings-source.php

@@ -0,0 +1,88 @@
+<?php
+/**
+ * Block Bindings API: WP_Block_Bindings_Source class.
+ *
+ *
+ * @package WordPress
+ * @subpackage Block Bindings
+ * @since 6.5.0
+ */
+
+/**
+ * Class representing block bindings source.
+ *
+ * This class is designed for internal use by the Block Bindings registry.
+ *
+ * @since 6.5.0
+ * @access private
+ *
+ * @see WP_Block_Bindings_Registry
+ */
+final class WP_Block_Bindings_Source {
+
+	/**
+	 * The name of the source.
+	 *
+	 * @since 6.5.0
+	 * @var string
+	 */
+	public $name;
+
+	/**
+	 * The label of the source.
+	 *
+	 * @since 6.5.0
+	 * @var string
+	 */
+	public $label;
+
+
+	/**
+	 * The function used to get the value from the source.
+	 *
+	 * @since 6.5.0
+	 * @var callable
+	 */
+	private $get_value_callback;
+
+	/**
+	 * Constructor.
+	 *
+	 * Do not use this constructor directly. Instead, use the
+	 * `WP_Block_Bindings_Registry::register` method or the `register_block_bindings_source` function.
+	 *
+	 * @since 6.5.0
+	 *
+	 * @param string $name               The name of the source.
+	 * @param array  $source_properties  The properties of the source.
+	 */
+	public function __construct( string $name, array $source_properties ) {
+		$this->name               = $name;
+		$this->label              = $source_properties['label'];
+		$this->get_value_callback = $source_properties['get_value_callback'];
+	}
+
+	/**
+	 * Retrieves the value from the source.
+	 *
+	 * @since 6.5.0
+	 *
+	 * @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.
+	 *
+	 * @return mixed The value of the source.
+	 */
+	public function get_value( array $source_args, $block_instance, string $attribute_name ) {
+		return call_user_func_array( $this->get_value_callback, array( $source_args, $block_instance, $attribute_name ) );
+	}
+
+	/**
+	 * Wakeup magic method.
+	 *
+	 * @since 6.5.0
+	 */
+	public function __wakeup() {
+		throw new \LogicException( __CLASS__ . ' should never be unserialized' );
+	}
+}