- Mocked messagePersistenceKey in event-controller-error-banner.test.ts and safe-guarded it in event-controller.ts to prevent TypeError.
- Updated thinking loop retry test expectations to handle new dynamic recoveredErrors structure.
- Updated schema version assertions in auth-storage-email-dedupe.test.ts to v5, preserving v6 for future schema test.
- Simulated scrollback commitment in event-controller-message-start.test.ts by rendering container and committing rows before advancing timers.
Four tightly-scoped hot-path fixes covering the highest-impact items in the
reporter's CPU profile (13.1 s profiled / 30 s window):
1. `event-controller.ts:handleEvent` no longer fires a blanket
`statusLine.invalidate() + ui.requestRender()` before every session event.
The pre-render was a leftover from #4145 when `updateEditorTopBorder()`
still eagerly rebuilt the border; the lazy provider added in #4145 made
it redundant. It fired on every `message_update`/`tool_execution_update`
during streaming — the pre-render's frame ran while the handler was
awaiting, then the handler's own `requestRender` scheduled a second
identical frame. Every handler that mutates visible state already calls
`requestRender()`.
2. `shimmer.ts:shimmerSegments` iterates the segment string in place instead
of building a code-point array with `Array.from(seg.text)` every animation
frame. Runs of same-tier chars are emitted via a single `slice` per run
rather than accumulating into `runBuf`. Surrogate pairs stay atomic — the
code-point index still advances by 1 per emoji. Microbench over 30k
frames: 45 ms → 18 ms (2.53x), allocation rate down from ~N-per-frame to
a handful per frame. New tests cover mixed BMP+surrogate and all-emoji
inputs. `Array.from` was the #1 self-time hotspot in the reporter's
profile at 10.2%.
3. `Markdown.setText` gains an equality guard mirroring `Text.setText`
(returns `false` when `text === #text`). Providers re-emit identical text
on ticks with no delta (throttled frames, reconciled tool-execution
updates); each of those now short-circuits instead of dropping
`#cachedLines` and forcing a full lex + wrap on the accumulated paragraph
(the reporter's #3 hotspot at 8.4%). New test asserts render-reference
stability + return-value semantics.
4. `SPINNER_RENDER_INTERVAL_MS` aligned with `SPINNER_GLYPH_ADVANCE_MS`
(both 80 ms). The previous 33 ms cadence emitted ~2.4 paints per glyph
step; the differential-output dedup only skips the write, not the
compose walk. Visually identical (glyph advance was already 12.5fps),
halves paints during tool execution.
Skipped (out of scope for a bug fix, deserve dedicated PRs):
- Freezing streaming prefix on single `\n` boundaries — correctness-bound
to `\n\n` block separators (CommonMark loose-list continuation).
- Compose-phase idle gate + adaptive-backpressure moving-average — need a
component-level dirty flag; the 200 ms cap in `#scheduleRender` was set
for a reason (#4145 tail-latency guard).
Tests updated: two IRC-expiry tests in event-controller-message-start.test.ts
that were asserting the pre-render's second `requestRender` call now expect
one.
Fixes#4353
EventController.handleEvent rebuilt the editor's status-line top border
synchronously on every session event via updateEditorTopBorder(). During
a long-running eval that fires 5-10 events/s, each rebuild ran
StatusLine.getTopBorder → #buildSegmentContext → getCachedContextBreakdown
→ session.getContextUsage → estimateTokens (with JSON.stringify per
toolCall block) — the render pipeline is throttled to ~30 fps, so most
rebuilds were dropped before painting. Combined with a scheduler that
collapsed cadenceDelay to zero whenever a frame overran the 33ms budget,
the TUI busy-looped at ~40-50% CPU.
Fix:
- Editor gains setTopBorderProvider(): a lazy builder invoked once per
editor render. InteractiveMode installs it in the constructor and on
setEditorComponent, so the rebuild coalesces to the render tempo
regardless of event rate.
- Delete updateEditorTopBorder wrapper (now equivalent to
ui.requestRender) and inline every call site.
- Add adaptive render backpressure: a frame that exceeds
MIN_RENDER_INTERVAL_MS inflates the next scheduling delay to
2 * last_frame_cost, capped at 200 ms, targeting a 50% render duty
cycle instead of pinning the CPU at t=0.
New regression tests:
- editor-top-border-provider.test.ts: provider fires exactly once per
render, wins over eager setTopBorder, falls back when cleared, gets
the correct availableWidth.
- adaptive-render-backpressure.test.ts: cheap frames keep the 33 ms
cadence, a slow frame idles proportionally, pathological frames are
capped at 200 ms.
Verified with bun test packages/tui/test (all 246 relevant tests pass)
and bun test packages/coding-agent/test/modes (455 tests pass). Three
pre-existing agent-session-handoff snapcompact failures on main are
unrelated (snapcompactSupportedChars binding).
Fixes#4145
- Added a check to restore the live "Working..." loader when streaming events occur after a transient status overlay clears the UI.
- Updated `ensureLoadingAnimation` to re-attach the animation to the status container if it is missing.
Added clearOptimisticUserMessage and replaceOptimisticUserMessage stubs to the EventController message_start test double so the optimistic-submission case no longer throws when the controller reconciles the signature.
Fixes#3199
- Capped live transcript IRC cards at four and evicted oldest cards when over limit.
- Reworked IRC card expiry handling to retire cards via timers only while live.
- Added rewrite-floor tracking so rewritten rows are not repeatedly promoted to scrollback.
- Handled frame shrink by re-anchoring windowTop and chunkTo at commit boundaries.
- Reset committedRows when the frame shrank into committed content to keep history immutable.
- Treated geometryChanged like overlay when advancing chunkTo to stabilize repaint commit timing.
- Updated regressions to assert stable scrollback prefixes and no clear-home/dclear repaint bytes.
- Centralized transcript spacing by stripping blank edges and inserting separators.
- Removed per-component leading spacers and empty placeholders that added extra gaps.
- Introduced TranscriptBlock grouping so related outputs render as single transcript children.
- Updated transcript-related tests to validate one-row block separators and blank-line trimming.
- Removed async image-link materialization between user message_start and addMessageToChat.
- Fixed steering bubbles rendering below the tool output they were sent to steer.
- Materialized clickable image links via synchronous blob-store fallback instead.
- Updated addMessageToChat in UI helpers and InteractiveModeContext to return rendered components instead of void.
- EventController now tracks IRC message components and removes them after a 10-second TTL, avoiding duplicate expiry scheduling per message signature.
- EventController dispose now clears all pending IRC expiry timers and tests were added for immediate render, TTL removal, duplicate suppression, and timer cleanup.
- Tracked locally submitted user signatures for both optimistic and streamed-queue submissions in interactive-mode context state.
- Updated user message_start handling to avoid re-clearing the editor and re-adding chat for locally originated messages.
- Cleared consumed local signatures on queued-message restore and added tests for queued, external, and optimistic message_start editor behavior.
can1357