`BusOutbound.audioLevel` carries a `Float rms` that `AudioLevelEmitter`
produces per audio frame (~100 Hz once the consumer is wired up).
Foundation's `JSONEncoder.NonConformingFloatEncodingStrategy` defaults
to `.throw`, so a single NaN — easy to land via a CoreAudio
over-/underflow or an all-zero buffer fed through certain RMS shapes —
would throw inside `WebviewBridge.sendRaw` and tear down the per-frame
bus path. The HUD-side consumer in `webview/packages/hud/src/bus/
client.ts:135` is currently a no-op (the ring shader is still on the
synthetic-sine animation from Plan 03-03), so the bug is LATENT, not
actively firing — but the clamp is cheap, defensive, and pins the
contract before the consumer activates.
Inline clamp at the encode site (`BusOutbound.encode(to:)` switch arm
for `.audioLevel`): replace non-finite floats with `0.0` via
`rms.isFinite ? rms : 0.0` immediately before `container.encode(_:)`.
No refactor of `AudioLevelEmitter` — the per-spec call here is
defensive at the serialization boundary, where every encoder-level
overflow path converges.
Two new unit tests in `CodableRoundTripTests`:
- `test_audioLevel_nanIsClampedToZero` — encodes `.audioLevel(rms: .nan)`,
decodes, asserts `rms == 0.0` and `rms.isFinite`.
- `test_audioLevel_infinityIsClampedToZero` — companion for ±∞ so a
future refactor cannot narrow the guard to NaN-only.
`swift test --package-path packages/Bus --filter CodableRoundTripTests`
passes (30 tests, +2 from this commit).
Closes#47
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
The runtime mismatch flagged by #37 was already fixed at the call sites
in `App/AppDelegate.swift:1631-1642` and `:2562-2575` — both routes now
reference `STTBackendSelector.backendSpeechAnalyzer` /
`backendWhisperKit` (snake_case) instead of the pre-2026-05-12 camelCase
string literals. The regression test
`STTBackendSwitchTests.testB5_canonicalConstantsRoundTripThroughMake`
already locks both halves of the contract:
1. The snake_case constants round-trip through `make(backend:)` without
hitting the unknown-backend default branch.
2. The pre-fix camelCase shape (`"whisperKit"`) DOES land in the
default branch and DOES emit an unknown-backend warning.
So the #37 close action is just to make that contract self-documenting
at the declaration site rather than relying on readers finding the test.
Add a doc-comment to the two `public static let backend*` constants that
explains the wire shape, names the regression test, references Issues
#29 + #37, and warns against renaming without updating `PerTurnSnapshot`
and the test in lockstep.
No code change; `swift test --package-path packages/Voice` continues to
pass (26 tests).
Closes#37
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
james.maesandClaude Opus 4.7