Interactivity API: Fatal error processing incorrect closed tags.

luisherranz · luisherranz · commit 03171e1d1250 · 2025-11-10T22:22:18.000Z
Fix for fatal errors caused by incorrect closing tags in HTML, such as `</br>`. In these cases, the `get_attribute_names_with_prefix` method of the `WP_HTML_Tag_Processor` returns `null`, and the Interactivity API was not handling this situation correctly. Props hugosolar, jonsurrell, darerodz. Fixes #63891. git-svn-id: https://develop.svn.wordpress.org/trunk@61197 602fd350-edb4-49c9-b593-d223f7449a82
diff --git a/src/wp-includes/interactivity-api/class-wp-interactivity-api.php b/src/wp-includes/interactivity-api/class-wp-interactivity-api.php
@@ -520,7 +520,12 @@ private function _process_directives( string $html ) {
 					array_pop( $tag_stack );
 				}
 			} else {
-				if ( 0 !== count( $p->get_attribute_names_with_prefix( 'data-wp-each-child' ) ) ) {
+				$each_child_attrs = $p->get_attribute_names_with_prefix( 'data-wp-each-child' );
+				if ( null === $each_child_attrs ) {
+					continue;
+				}
+
+				if ( 0 !== count( $each_child_attrs ) ) {
 					/*
 					 * If the tag has a `data-wp-each-child` directive, jump to its closer
 					 * tag because those tags have already been processed.
diff --git a/tests/phpunit/tests/interactivity-api/wpInteractivityAPI.php b/tests/phpunit/tests/interactivity-api/wpInteractivityAPI.php
@@ -1256,6 +1256,31 @@ public static function data_html_with_unbalanced_tags() {
 		);
 	}
 
+	/**
+	 * Tests that the `process_directives` handles self-closing BR tags without
+	 * causing fatal errors and processes directives correctly.
+	 *
+	 * @ticket 63891
+	 * @covers ::process_directives
+	 */
+	public function test_process_directives_handles_br_self_closing_tags_with_invalid_closers() {
+		$this->interactivity->state(
+			'myPlugin',
+			array(
+				'id' => 'some-id',
+			)
+		);
+
+		$html = '</br><div data-wp-bind--id="myPlugin::state.id">Content</div>';
+
+		$processed_html = $this->interactivity->process_directives( $html );
+
+		$p = new WP_HTML_Tag_Processor( $processed_html );
+		$p->next_tag( 'div' );
+
+		$this->assertSame( 'some-id', $p->get_attribute( 'id' ) );
+	}
+
 	/**
 	 * Tests that the `process_directives` process the HTML outside a SVG tag.
 	 *
