diff --git a/packages/api/test/nfts-upload.spec.js b/packages/api/test/nfts-upload.spec.js
index 5e20c4d252..3e8ce9cb8a 100644
--- a/packages/api/test/nfts-upload.spec.js
+++ b/packages/api/test/nfts-upload.spec.js
@@ -975,7 +975,13 @@ async function createListeningMockW3up() {
   const serverAddress = server.address()
   if (typeof serverAddress === 'string')
     throw new Error('server.address() must not return a string')
-  const url = new URL(`http://localhost:${serverAddress?.port ?? ''}`)
+  const urlString = `http://localhost:${serverAddress?.port ?? ''}`
+  let url
+  try {
+    url = new URL(urlString)
+  } catch (error) {
+    throw new Error(`unable to parse URL from "${urlString}"`, { cause: error })
+  }
   return {
     get requestCount() {
       return requestCount