Block Hooks: Fix context in update_ignored_hooked_blocks_postmeta.

Ensure that the `$context` arg passed from `update_ignored_hooked_blocks_postmeta` to `apply_block_hooks_to_content` (and from there, to filters such as `hooked_block_types` and `hooked_block`) has the correct type (`WP_Post`).

Filters hooked to `hooked_block_types` etc can typically include checks that conditionally insert a hooked block depending on `$context`. Prior to this changeset, a check like `if ( $context instanceof WP_Post )` would incorrectly fail, as `$context` would be a `stdClass` instance rather than a `WP_Post`. As a consequence, a hooked block inside of a Navigation post object that was modified by the user would not be marked as ignored by `update_ignored_hooked_blocks_postmeta`, and thus be erroneosly re-inserted by the Block Hooks algorithm.

Props bernhard-reiter.
Fixes #62639.

git-svn-id: https://develop.svn.wordpress.org/trunk@59482 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/blocks.php

@@ -1217,6 +1217,7 @@ function update_ignored_hooked_blocks_postmeta( $post ) {
 	$existing_post = get_post( $post->ID );
 	// Merge the existing post object with the updated post object to pass to the block hooks algorithm for context.
 	$context          = (object) array_merge( (array) $existing_post, (array) $post );
+	$context          = new WP_Post( $context ); // Convert to WP_Post object.
 	$serialized_block = apply_block_hooks_to_content( $markup, $context, 'set_ignored_hooked_blocks_metadata' );
 	$root_block       = parse_blocks( $serialized_block )[0];
 

tests/phpunit/tests/blocks/updateIgnoredHookedBlocksPostMeta.php

@@ -193,4 +193,31 @@ public function test_update_ignored_hooked_blocks_postmeta_dont_modify_if_no_pos
 			'Post content did not match the original markup.'
 		);
 	}
+
+	/**
+	 * @ticket 62639
+	 */
+	public function test_update_ignored_hooked_blocks_postmeta_sets_correct_context_type() {
+		$action = new MockAction();
+		add_filter( 'hooked_block_types', array( $action, 'filter' ), 10, 4 );
+
+		$original_markup    = '<!-- wp:navigation-link {"label":"News","type":"page","id":2,"url":"http://localhost:8888/?page_id=2","kind":"post-type"} /-->';
+		$post               = new stdClass();
+		$post->ID           = self::$navigation_post->ID;
+		$post->post_content = $original_markup;
+		$post->post_type    = 'wp_navigation';
+
+		$post = update_ignored_hooked_blocks_postmeta( $post );
+
+		$args     = $action->get_args();
+		$contexts = array_column( $args, 3 );
+
+		foreach ( $contexts as $context ) {
+			$this->assertInstanceOf(
+				WP_Post::class,
+				$context,
+				'The context passed to the hooked_block_types filter is not a WP_Post instance.'
+			);
+		}
+	}
 }