The spinner (.session-state-indicator.is-streaming) can remain spinning
indefinitely on completed sessions when the INFLIGHT in-memory cache is
not cleaned up due to abnormal stream termination (page refresh, network
disconnect, gateway restart).
Add a staleness guard in _isSessionLocallyStreaming: if the server
reports is_streaming=false and last_message_at is older than 5 minutes,
force the streaming state to false regardless of stale INFLIGHT entries.
- Session.composer_draft field: {text, files} stored in session JSON
- POST+GET /api/session/draft endpoint for save/load
- loadSession: save draft before switch, restore from S.session.composer_draft
- textarea input: debounced 400ms auto-save to server
- send(): clear draft after message is sent
- lockComposerForClarify(): save draft before card locks composer
- _restoreComposerDraft: clears textarea when target has no draft, guards
against stale responses racing new session loads, exact text comparison
- Session.compact(): includes composer_draft in response
- Fix: use handler.command instead of parsed.method (ParseResult has no .method)
Co-authored-by: Minimax <noreply@minimax.io>
The originally-proposed fix (gate _ensureAllMessagesLoaded on the existing
_loadingOlder flag) does not actually close the race. By the time the
prefetch reaches its post-await body, it has already cleared the entry-
gate that reads _loadingOlder, so a same-flag check inside the resolved
callback would be a no-op for an in-flight request.
The actual fix is two-pronged:
1. New module-scoped _messagesGeneration counter, bumped every time
S.messages is wholesale-replaced. _loadOlderMessages snapshots it
BEFORE its await and re-checks after — if it changed, the prepend
is aborted. This is the canonical async-invalidation pattern.
2. _ensureAllMessagesLoaded now claims the _loadingOlder mutex around
its body so a new prefetch cannot start mid-replace and concurrent
ensure-all calls (rapid double-click on Start) serialize cleanly.
It bumps the generation token before mutating S.messages, yields
until any in-flight prefetch finishes, and resets _oldestIdx so a
subsequent prefetch cannot request stale older messages.
Also adds the same-session / _loadingSessionId guards that the original
ensure-all body was missing post-await — if the user switched sessions
mid-flight, the old code would happily overwrite the new session's
messages with the previous session's full history.
12 new regression tests in tests/test_issue1937_endless_scroll_jumpstart_race.py
lock in: generation token declaration, bump-helper presence, snapshot-
before-await ordering, post-await-abort behaviour, mutex acquisition and
finally-release, yield-then-claim ordering when a prefetch is in flight,
generation bump during the wait phase, _oldestIdx reset, and the new
session-switch guard.
Closes#1937.
