1 files changed, 13 insertions, 1 deletions
diff --git a/tests/server.py b/tests/server.py
index c447d5e4c4..b1730fcc8d 100644
--- a/tests/server.py
+++ b/tests/server.py
@@ -266,7 +266,12 @@ class FakeSite:
     site_tag = "test"
     access_logger = logging.getLogger("synapse.access.http.fake")
 
-    def __init__(self, resource: IResource, reactor: IReactorTime):
+    def __init__(
+        self,
+        resource: IResource,
+        reactor: IReactorTime,
+        experimental_cors_msc3886: bool = False,
+    ):
         """
 
         Args:
@@ -274,6 +279,7 @@ class FakeSite:
         """
         self._resource = resource
         self.reactor = reactor
+        self.experimental_cors_msc3886 = experimental_cors_msc3886
 
     def getResourceFor(self, request):
         return self._resource
@@ -356,6 +362,12 @@ def make_request(
     # Twisted expects to be at the end of the content when parsing the request.
     req.content.seek(0, SEEK_END)
 
+    # Old version of Twisted (<20.3.0) have issues with parsing x-www-form-urlencoded
+    # bodies if the Content-Length header is missing
+    req.requestHeaders.addRawHeader(
+        b"Content-Length", str(len(content)).encode("ascii")
+    )
+
     if access_token:
         req.requestHeaders.addRawHeader(
             b"Authorization", b"Bearer " + access_token.encode("ascii")