CI flake: TypeScript - Tests

[clockwork-labs-bot]

Detected by CI Gremlin after a failed GitHub Actions attempt succeeded on rerun.

Tests:

• TypeScript - Tests

Error:
Error: Channel closed
❯ target.send node:internal/child_process:753:16

Failed job runs:

• https://github.com/clockworklabs/SpacetimeDB/actions/runs/35994441599/job/107617168791 (TypeScript - Tests, attempt 1 -> 2)

Timeout detection:

• none

Context:

• none

[clockwork-labs-bot]

Exact-attempt diagnosis: run 35994441599, job 107617168791, attempt 1, TypeScript - Tests, head 1afc587eb5bb24c940d7d236fe97634962c98b6f / PR #5967. Setup, checkout, pnpm setup, Rust setup, artifact download, and artifact extraction all succeeded. The failure was in Run TypeScript tests, inside cargo ci typescript-test -> cargo run --timings --package ci-typescript-test -- -> pnpm test.

Failure signature: while building crates/bindings-typescript with tsup v8.5.0 under Node v22.23.3, a Vitest worker process hit a Node/V8 internal fatal:

# Fatal error in , line 0
# unreachable code
V8_Fatal(char const*, ...) [node (vitest 7)]
...turboshaft::MachineLoweringReducer...
Unhandled Rejection
Error: Channel closed
target.send node:internal/child_process:753:16
Serialized Error: { code: 'ERR_IPC_CHANNEL_CLOSED' }

Root cause: the Channel closed error is secondary. The worker process had already aborted inside V8/Turboshaft during the TypeScript SDK build/test workload, then tinypool/Vitest tried to send to the dead worker IPC channel. This is a Node/V8 internal compiler/runtime abort, not a TypeScript assertion failure and not a repo test failure.

Suggested title: CI flake: TypeScript SDK build crashes in Node/V8 unreachable code

Duplicate search: searched the public tracker for the bare fatal headline (unreachable code), the V8 marker (V8_Fatal), the secondary IPC symptom (Channel closed, ERR_IPC_CHANNEL_CLOSED, tinypool), and TypeScript build/job terms. Similar public tickets exist:

• CI flake: v8 internal error during build #5366 tracks Node/V8 internal aborts during TypeScript/TS build workloads and is the best duplicate candidate.
• CI flake: TypeScript - Tests #5939 is a recent same-family TypeScript - Tests Node/V8 internal abort, already pointing at CI flake: v8 internal error during build #5366.
• CI flake: Lints #5929 is same broader V8 fatal family in Lints, but a different workflow path.

Top duplicate candidate: #5366. Leaving this ticket open because #5366 is not one of the configured auto-close targets.