send an empty payload for NO_STATUS_RCVD

CHANGELOG.rst

@@ -4,6 +4,8 @@ Release History
 Unreleased
 ----------
 
+- Bugfix: When a close frame with status NO_STATUS_RCVD is sent, send
+  and empty payload.
 - <ToDo: add new entries here>
 
 

src/wsproto/frame_protocol.py

@@ -569,6 +569,8 @@ def received_frames(self) -> Generator[Frame, None, None]:
 
     def close(self, code: Optional[int] = None, reason: Optional[str] = None) -> bytes:
         payload = bytearray()
+        if code is CloseReason.NO_STATUS_RCVD:
+            code = None
         if code is None and reason is not None:
             raise TypeError("cannot specify a reason without a code")
         if code in LOCAL_ONLY_CLOSE_REASONS:

test/test_frame_protocol.py

@@ -1036,9 +1036,14 @@ def test_reasoned_but_uncoded_close(self) -> None:
         with pytest.raises(TypeError):
             proto.close(reason="termites")
 
-    def test_local_only_close_reason(self) -> None:
+    def test_no_status_rcvd_close_reason(self) -> None:
         proto = fp.FrameProtocol(client=False, extensions=[])
         data = proto.close(code=fp.CloseReason.NO_STATUS_RCVD)
+        assert data == b"\x88\x00"
+
+    def test_local_only_close_reason(self) -> None:
+        proto = fp.FrameProtocol(client=False, extensions=[])
+        data = proto.close(code=fp.CloseReason.ABNORMAL_CLOSURE)
         assert data == b"\x88\x02\x03\xe8"
 
     def test_ping_without_payload(self) -> None: