Ticket #33995: 33995.patch

src/wp-includes/class-http.php

@@ -159 +159 @@
                         $r['_redirection'] = $r['redirection'];
 
                 /**
-                 * Filter whether to preempt an HTTP request's return.
+                 * Filter whether to preempt an HTTP request's return value.
                  *
-                 * Returning a truthy value to the filter will short-circuit
-                 * the HTTP request and return early with that value.
+                 * Returning a non-false value from the filter will short-circuit the HTTP request and return early with
+                 * that value. A filter should return either:
+                 *
+                 *  - An array containing 'headers', 'body', 'response', 'cookies', and 'filename' elements
+                 *  - A `WP_Error` instance
+                 *  - boolean false (to avoid short-circuiting the response)
+                 *
+                 * Returning any other value may result in unexpected behaviour.
                  *
                  * @since 2.9.0
                  *
-                 * @param bool   $preempt Whether to preempt an HTTP request return. Default false.
-                 * @param array  $r       HTTP request arguments.
-                 * @param string $url     The request URL.
+                 * @param bool|array|WP_Error $preempt Whether to preempt an HTTP request's return value. Default false.
+                 * @param array               $r       HTTP request arguments.
+                 * @param string              $url     The request URL.
                  */
                 $pre = apply_filters( 'pre_http_request', false, $r, $url );
                 if ( false !== $pre )