From dda2c278cda40b566548f71f1db6ac8feee32017 Mon Sep 17 00:00:00 2001
From: Kegan Dougal <kegan@matrix.org>
Date: Thu, 25 Jun 2020 14:38:44 +0100
Subject: [PATCH] Fix tests

---
 federationsender/internal/perform.go | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/federationsender/internal/perform.go b/federationsender/internal/perform.go
index a56d70ca2..831622efe 100644
--- a/federationsender/internal/perform.go
+++ b/federationsender/internal/perform.go
@@ -91,6 +91,8 @@ func (r *FederationSenderInternalAPI) PerformJoin(
 	var httpErr gomatrix.HTTPError
 	if ok := errors.As(lastErr, &httpErr); ok {
 		httpErr.Message = string(httpErr.Contents)
+		// Clear the wrapped error, else serialising to JSON (in polylith mode) will fail
+		httpErr.WrappedError = nil
 		response.LastError = &httpErr
 	} else {
 		response.LastError = &gomatrix.HTTPError{