Enabling background notifications failed with "Invalid filter". The
subscription asked to be notified about mail matching:
filter: { inMailbox: null, notKeyword: "$seen" }
`inMailbox: null` meant "the inbox" in my head and nothing at all to
Stalwart, which needs a mailbox id there. It refused the whole
subscription, so the feature did not work at all for anyone who tried
it.
The Inbox's id is now passed in and used. Where it is not known the
condition is left out rather than sent empty: notifying more widely is a
worse default than filtering to the Inbox, but it is a working one, and
sending a malformed filter is not a fallback.
Two reasons this got out, both worth fixing rather than just the bug:
- The tests checked the properties list and its ordering, and never
looked at the filter. There is now one that walks every condition
and fails on a null or undefined value, for both the known-inbox and
unknown-inbox cases.
- The mock accepted it happily, so nothing local disagreed with the
code. It now refuses a filter condition with a null value and
answers "Invalid filter.", which is what the live server said.
Reproduced: the old payload is rejected, the new one accepted.