`commit`'s success handler writes the dragged list into the detail cache — round 6's fix, so a
re-entry inside the 30s staleTime renders the accepted order without a request — but then invalidated
only the LIST key, while the YouTube sibling it cites invalidates both. `next` is the membership of
the render that started the drag, and `reorder_playlist` only touches the rating_keys it is handed,
so it never ratifies that list: anything that landed meanwhile was clobbered by the write with
nothing scheduled to correct it. `commit` sets no busy flag either, so a removal really can complete
while a reorder is in flight, and with staleTime 30s and refetchOnWindowFocus off the phantom row
stayed on screen for as long as the view was mounted — and the next drag persisted an order built
from it.
Round 6's test had to be re-pointed, because it was written in a world with no refetch: its mock
answered the pre-reorder order forever, which a server that just accepted the write cannot do. It now
holds the refetch open instead, so it still pins what round 6 actually fixed — the cache is right
WITHOUT waiting for a request — and would fail if the write were deleted. Both halves are
mutation-checked against each other.
peter
63bf1bca78