When a homeserver (Synapse) performs a partial state join to a room, it
may emit device_lists.changed entries for users it thinks are in the
room, despite the room not appearing in the /sync response yet. This is
questionable behaviour, but not forbidden by the spec. Once the
homeserver is fully joined to the room, it may emit another round of
device_lists.changed entries for users it knows are definitely in the
room.
These extra entries were causing test cases to advance prematurely and
randomly fail. To fix the tests, we explicitly check for join events
alongside the device_lists.changed entries produced by joins. In
effect, we ensure that homeservers are fully joined to the test rooms
before continuing the rest of the tests.
For consistency, we also check for leave events alongside
device_lists.left entries.
When a homeserver (Synapse) performs a partial state join to a room, it may emit
device_lists.changedentries for users it thinks are in the room, despite the room not appearing in the /sync response yet. This is questionable behaviour, but not forbidden by the spec. Once the homeserver is fully joined to the room, it may emit another round ofdevice_lists.changedentries for users it knows are definitely in the room.These extra entries were causing test cases to advance prematurely and randomly fail. To fix the tests, we explicitly check for join events alongside the
device_lists.changedentries produced by joins. In effect, we ensure that homeservers are fully joined to the test rooms before continuing the rest of the tests.For consistency, we also check for leave events alongside
device_lists.leftentries.Fixes https://github.com/matrix-org/synapse/issues/14103.