Await Missing in Fire-and-Forget Debugging Lab

Await Missing in Fire-and-ForgetEvents & ConcurrencyEasyPreparing workspaceAutosaved

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Incident Dossier

Await Missing in Fire-and-Forget

An ingestion pipeline processes a queue of records. When one record's worker rejects, the whole batch is supposed to reject so the caller can dead-letter it. Instead, the batch reports success and a stray rejection appears later in the logs.

Initial failing signalrunBatch resolves instead of rejectingExpected runBatch rejects with a message containing the failing item id · received assert.rejects fails: runBatch resolves to { processed: N }

Progress

1Reproduce the bugRun checks

2Edit the fixOpen

3Pass checksOpen

4Submit fixOpen

Reproduction Steps

Run npm test.
Read the rejection contract for runBatch and the loop body in src/processor.js.
Trace what happens to the promise returned by the per-item call.
Make the failing item's rejection land inside the surrounding try/catch.

Focus Mode

Start

src/processor.js

Likely area

src/processor.js

Progressive hints

Hints reveal broad direction first, then narrow toward the suspect path without showing hidden tests or exact solution code.

TopicEvents & Concurrency

DifficultyEasy

Est. time12 min

Workspacecreating

Explorer

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Evidence Map

Failing signal loaded from challenge API
Workspace files loaded from workspace API
Results rendered only after API run/submit

Autosaved

workspace

Outputread-onlyready$ workspace boot

Workspace booting...