From aaeab2f3f5a06b266b6a83a3776b514c77a1d475 Mon Sep 17 00:00:00 2001
From: Dominik Schilling <dominikschilling+git@gmail.com>
Date: Sat, 23 May 2020 14:36:09 +0000
Subject: [PATCH] Rest API: Ensure `rest_ensure_response()` upgrades
 `WP_HTTP_Response` to `WP_REST_Response`.

An instance of `WP_HTTP_Response` doesn't ensure that the required methods used in `WP_REST_Server::dispatch()` exist, currently causing a fatal error.

Props ali11007, TimothyBlynJacobs, ocean90.
Fixes #49495.
Built from https://develop.svn.wordpress.org/trunk@47849


git-svn-id: http://core.svn.wordpress.org/trunk@47625 1a063a9b-81f0-0310-95a4-ce76da25c4cd
---
 wp-includes/rest-api.php                      | 22 ++++++++++++++-----
 wp-includes/rest-api/class-wp-rest-server.php | 12 +++++-----
 wp-includes/version.php                       |  2 +-
 3 files changed, 23 insertions(+), 13 deletions(-)

diff --git a/wp-includes/rest-api.php b/wp-includes/rest-api.php
index 11eb2b71ad..e408522ab6 100644
--- a/wp-includes/rest-api.php
+++ b/wp-includes/rest-api.php
@@ -506,26 +506,36 @@ function rest_ensure_request( $request ) {
 /**
  * Ensures a REST response is a response object (for consistency).
  *
- * This implements WP_HTTP_Response, allowing usage of `set_status`/`header`/etc
+ * This implements WP_REST_Response, allowing usage of `set_status`/`header`/etc
  * without needing to double-check the object. Will also allow WP_Error to indicate error
  * responses, so users should immediately check for this value.
  *
  * @since 4.4.0
  *
- * @param WP_HTTP_Response|WP_Error|mixed $response Response to check.
- * @return WP_REST_Response|mixed If response generated an error, WP_Error, if response
- *                                is already an instance, WP_HTTP_Response, otherwise
- *                                returns a new WP_REST_Response instance.
+ * @param WP_REST_Response|WP_Error|WP_HTTP_Response|mixed $response Response to check.
+ * @return WP_REST_Response|WP_Error If response generated an error, WP_Error, if response
+ *                                   is already an instance, WP_REST_Response, otherwise
+ *                                   returns a new WP_REST_Response instance.
  */
 function rest_ensure_response( $response ) {
 	if ( is_wp_error( $response ) ) {
 		return $response;
 	}
 
-	if ( $response instanceof WP_HTTP_Response ) {
+	if ( $response instanceof WP_REST_Response ) {
 		return $response;
 	}
 
+	// While WP_HTTP_Response is the base class of WP_REST_Response, it doesn't provide
+	// all the required methods used in WP_REST_Server::dispatch().
+	if ( $response instanceof WP_HTTP_Response ) {
+		return new WP_REST_Response(
+			$response->get_data(),
+			$response->get_status(),
+			$response->get_headers()
+		);
+	}
+
 	return new WP_REST_Response( $response );
 }
 
diff --git a/wp-includes/rest-api/class-wp-rest-server.php b/wp-includes/rest-api/class-wp-rest-server.php
index 771c3b9fbe..0ab94bbbde 100644
--- a/wp-includes/rest-api/class-wp-rest-server.php
+++ b/wp-includes/rest-api/class-wp-rest-server.php
@@ -969,9 +969,9 @@ class WP_REST_Server {
 				 *
 				 * @since 4.7.0
 				 *
-				 * @param WP_HTTP_Response|WP_Error $response Result to send to the client. Usually a WP_REST_Response or WP_Error.
-				 * @param array                     $handler  Route handler used for the request.
-				 * @param WP_REST_Request           $request  Request used to generate the response.
+				 * @param WP_REST_Response|WP_HTTP_Response|WP_Error|mixed $response Result to send to the client. Usually a WP_REST_Response or WP_Error.
+				 * @param array                                            $handler  Route handler used for the request.
+				 * @param WP_REST_Request                                  $request  Request used to generate the response.
 				 */
 				$response = apply_filters( 'rest_request_before_callbacks', $response, $handler, $request );
 
@@ -1032,9 +1032,9 @@ class WP_REST_Server {
 				 *
 				 * @since 4.7.0
 				 *
-				 * @param WP_HTTP_Response|WP_Error $response Result to send to the client. Usually a WP_REST_Response or WP_Error.
-				 * @param array                     $handler  Route handler used for the request.
-				 * @param WP_REST_Request           $request  Request used to generate the response.
+				 * @param WP_REST_Response|WP_HTTP_Response|WP_Error|mixed $response Result to send to the client. Usually a WP_REST_Response or WP_Error.
+				 * @param array                                            $handler  Route handler used for the request.
+				 * @param WP_REST_Request                                  $request  Request used to generate the response.
 				 */
 				$response = apply_filters( 'rest_request_after_callbacks', $response, $handler, $request );
 
diff --git a/wp-includes/version.php b/wp-includes/version.php
index 1d5be769f0..ae6b843524 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -13,7 +13,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.5-alpha-47848';
+$wp_version = '5.5-alpha-47849';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.