fix(kotlin): gate synthesizeStream on ensureServicesReady before the voice lookup

[ayaangazali]

What

RunAnywhere.synthesizeStream(...) checks isInitialized and then goes straight to the model lifecycle to find a loaded speech synthesis voice, without waiting for phase 2 initialisation.

If a caller starts streaming before phase 2 finishes, currentModel(...) reports found = false and the Flow closes without emitting a single output, so a voice that is actually loaded looks to the caller like no voice at all.

One line: call ensureServicesReady() before the lifecycle query.

Why

Every sibling on this path already gates on it, so the streaming variant is the odd one out:

• synthesize(...) (same file) calls ensureServicesReady() immediately before the identical currentModel(MODEL_CATEGORY_SPEECH_SYNTHESIS) query.
• transcribeStream(...) in RunAnywhereSTT.kt calls it before its own lifecycle query.
• Swift's synthesizeStream awaits ensureServicesReady() before reading loadedModelSnapshot(category: .speechSynthesis).

The call is left unwrapped to match transcribeStream in this SDK. I deliberately did not copy Swift's do/catch that finishes the stream silently on a phase 2 failure, since swallowing that error would leave the caller with an empty stream and no way to tell why.

Testing

From sdk/runanywhere-kotlin (JDK 17):

• ./gradlew :compileDebugKotlin :ktlintMainSourceSetCheck -Prunanywhere.useLocalNatives=false — BUILD SUCCESSFUL.

Scoped to the root module because :modules:runanywhere-core-onnx:downloadJniLibs cannot fetch native libs on this machine. No test added: this is a one-line ordering fix on a path whose behaviour is validated end to end through the example apps.

🤖 Generated with Claude Code

Summary by CodeRabbit

• Bug Fixes
  • Improved text-to-speech streaming reliability by ensuring required services are ready before voice selection and playback begin.

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ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

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Run ID: 2bcfe3e6-3ded-4db5-91a6-25ea52383e85

📥 Commits

Reviewing files that changed from the base of the PR and between 1965930 and 29215c0.

📒 Files selected for processing (1)

• sdk/runanywhere-kotlin/src/main/kotlin/com/runanywhere/sdk/public/extensions/TTS/RunAnywhereTTS.kt

🚧 Files skipped from review as they are similar to previous changes (1)

• sdk/runanywhere-kotlin/src/main/kotlin/com/runanywhere/sdk/public/extensions/TTS/RunAnywhereTTS.kt

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📝 Walkthrough

Walkthrough

The TTS synthesizeStream path now waits for Phase 2 service initialization before it queries the loaded voice and starts native streaming.

Changes

TTS readiness

Layer / File(s)	Summary
Gate TTS streaming on service readiness sdk/runanywhere-kotlin/src/main/kotlin/com/runanywhere/sdk/public/extensions/TTS/RunAnywhereTTS.kt	synthesizeStream now calls ensureServicesReady() before the lifecycle voice query and native streaming start.

Estimated code review effort: 1 (Trivial) | ~2 minutes

Possibly related PRs

• RunanywhereAI/runanywhere-sdks#572: Both changes modify RunAnywhereTTS.synthesizeStream; this PR adds readiness gating, while #572 changes cancellation and error handling.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly identifies the Kotlin streaming fix and the readiness check added before the voice lookup.
Description check	✅ Passed	The description clearly explains the bug, fix rationale, validation command, scope, and test limitation.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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[ayaangazali]

kotlin-android failed on the known flaky timing test, not on this change:

HandleStreamAdapterTest > cancel to native latency is bounded FAILED
    java.lang.AssertionError at HandleStreamAdapterTest.kt:310
98 tests completed, 1 failed

That test asserts a 250 ms wall-clock budget for coroutine cancellation to propagate across five consumers on Dispatchers.Default, which is inherently sensitive on a shared runner.

The clearest evidence that neither diff causes it: the exact same test failed in the same way on #611, which changes only TypeScript and contains no Kotlin at all. It also failed once on #608 (a Dart-only change) and then passed on an identical re-run. kotlin-android is green on main.

Re-triggering with an unchanged diff rather than pushing a fix for it.

[shubhammalhotra28]

thanks for the fix @ayaangazali