Before this change, every navigateTree → renderInitialMessages call path
performed two independent O(N) session-tree walks:
1. agent-session.ts:6586 buildDisplaySessionContext() [inside navigateTree]
2. ui-helpers.ts:402 sessionManager.buildSessionContext() [inside renderInitialMessages]
Changes:
- agent-session.ts: navigateTree() now calls sessionManager.buildSessionContext()
once, derives the display (deobfuscated) context from the raw result, and
returns the raw SessionContext in the result object.
- ui-helpers.ts: renderInitialMessages() accepts an optional prebuiltContext
parameter; reuses it when provided, falls back to buildSessionContext() otherwise.
- interactive-mode.ts: forwards prebuiltContext through the wrapper.
- modes/types.ts: updates InteractiveModeContext interface to match.
- selector-controller.ts: passes result.sessionContext from navigateTree into
renderInitialMessages(), closing the deduplication loop.
Bench (100-msg session, 200 iterations):
two walks [BEFORE]: 0.0702ms/op
one walk [AFTER]: 0.0298ms/op
Saved: 0.0404ms/navigation (57.5% reduction per navigate)
Tests: render-initial-messages-dedupe.test.ts asserts buildSessionContext is
called 0 times when a prebuilt context is passed, 1 time as fallback.
- Migrated timing measurements from `performance.now()` to `Bun.nanoseconds()` for higher precision benchmarking across all benchmark and timing-sensitive code.
- Updated elapsed time calculations to convert nanoseconds to milliseconds using division by 1e6 to maintain consistent time units.
- Increased benchmark precision from 4 to 6 decimal places for per-operation timing measurements.
- Refactored grep benchmark to use averaged timing values instead of storing individual iteration times, reducing memory overhead.
- Added native text utilities in pi-natives (visible width, truncation, slicing, segment extraction)
- Wired pi-tui to use native implementations with short-string JS fast path
- Optimized key matching via cached parsed key ids
- Refactored visual truncation to reuse Text instances
- Reduced theme color lookups by switching from Map to plain records
- Regenerated WASM artifacts
Benchmarks (after vs before, lower is better):
- truncateToWidth/ansi: 20.37ms vs 38.13ms (2000 iters)
- sliceWithWidth/ansi: 5.12ms vs 20.39ms
- extractSegments/ansi: 8.92ms vs 27.60ms
- truncateToVisualLines: 3.51ms vs 411.55ms (500 iters)
- visibleWidth/ansi: 0.24ms vs 0.31ms
cognitive