fixes

runtime/fastly/builtins/fetch/request-response.cpp

@@ -1796,7 +1796,7 @@ JSObject *Request::create(JSContext *cx, JS::HandleObject requestInstance, JS::H
     if (!url_instance)
       return nullptr;
 
-    JS::RootedObject parsedURL(cx, URL::create(cx, url_instance, input, WorkerLocation::url));
+    JS::RootedObject parsedURL(cx, URL::create(cx, url_instance, input, builtins::Fastly::baseURL));
 
     // 2.  If `parsedURL` is failure, then throw a `TypeError`.
     if (!parsedURL) {

tests/wpt-harness/post-harness.js

@@ -1,9 +1,8 @@
 /* eslint-env serviceworker */
 /* global add_completion_callback setup done */
-import { enableDebugLogging, setDefaultBackend, setBaseURL } from "fastly:experimental";
+import { enableDebugLogging, setBaseURL } from "fastly:experimental";
 
 enableDebugLogging(true);
-setDefaultBackend("wpt");
 
 let completionPromise = new Promise((resolve) => {
     add_completion_callback(function(tests, harness_status, asserts) {

types/experimental.d.ts

@@ -17,6 +17,13 @@ declare module "fastly:experimental" {
    */
   export function setBaseURL(base: URL | null | undefined): void;
   /**
+   * 
+   * Set the default backend to use when dynamic backends are disabled.
+   * 
+   * For backwards compatibility, unless allowDynamicBackends has been explicitly
+   * called before invoking this function, it will disable dynamic backends when it is called
+   * in order to apply, as if calling allowDynamicBackends(false).
+   * 
    * @experimental
    */
   export function setDefaultBackend(backend: string): void;