REST API: Allow comment content to be updated to empty when allow_empty_comment filter returns true

kadamwhite · kadamwhite · commit 1c9e7ef703fe · 2025-10-15T20:28:51.000Z
This filter was already respected during comment creation, but not updates. This was inconsistent between POST and PUT, and prevented erasing content of moderated comments via the API without deleting the entire object. Props adamsilverstein, kadamwhite, davidbaumwald, mukesh27, timothyblynjacobs. Fixes #64049. git-svn-id: https://develop.svn.wordpress.org/trunk@60937 602fd350-edb4-49c9-b593-d223f7449a82
diff --git a/src/wp-includes/rest-api/endpoints/class-wp-rest-comments-controller.php b/src/wp-includes/rest-api/endpoints/class-wp-rest-comments-controller.php
@@ -859,8 +859,7 @@ public function update_item( $request ) {
 			if ( is_wp_error( $prepared_args ) ) {
 				return $prepared_args;
 			}
-
-			if ( isset( $prepared_args['comment_content'] ) && empty( $prepared_args['comment_content'] ) ) {
+			if ( ! $this->check_is_comment_content_allowed( $prepared_args ) ) {
 				return new WP_Error(
 					'rest_comment_content_invalid',
 					__( 'Invalid comment content.' ),
@@ -1903,6 +1902,10 @@ public function check_comment_author_email( $value, $request, $param ) {
 	 * @return bool True if the content is allowed, false otherwise.
 	 */
 	protected function check_is_comment_content_allowed( $prepared_comment ) {
+		if ( ! isset( $prepared_comment['comment_content'] ) ) {
+			return true;
+		}
+
 		$check = wp_parse_args(
 			$prepared_comment,
 			array(
diff --git a/tests/phpunit/tests/rest-api/rest-comments-controller.php b/tests/phpunit/tests/rest-api/rest-comments-controller.php
@@ -2493,6 +2493,30 @@ public function test_update_item_no_content() {
 		$this->assertErrorResponse( 'rest_comment_content_invalid', $response, 400 );
 	}
 
+	/**
+	 * @ticket 64049
+	 */
+	public function test_update_item_no_content_allow_empty_comment_filter() {
+		$post_id = self::factory()->post->create();
+
+		wp_set_current_user( self::$admin_id );
+
+		$request = new WP_REST_Request( 'PUT', sprintf( '/wp/v2/comments/%d', self::$approved_id ) );
+		$request->set_param( 'author_email', 'another@email.com' );
+
+		// Sending a request without content is fine.
+		$response = rest_get_server()->dispatch( $request );
+		$this->assertSame( 200, $response->get_status() );
+
+		// Sending a request with empty comment content is also fine.
+		$request->set_param( 'author_email', 'yetanother@email.com' );
+		$request->set_param( 'content', '' );
+		add_filter( 'allow_empty_comment', '__return_true' );
+		$response = rest_get_server()->dispatch( $request );
+		remove_filter( 'allow_empty_comment', '__return_true' );
+		$this->assertSame( 200, $response->get_status() );
+	}
+
 	public function test_update_item_no_change() {
 		$comment = get_comment( self::$approved_id );
 
