Time: 0:00
Test a custom input to verify an edge case (e.g. empty lists, negative numbers, duplicates).
This bug belongs to the async and race conditions pattern
A missing await, results in the wrong order, and updates that overwrite each other under load.
What went wrong: the callback is async, so each one returns a promise. map gives a list of promises, not numbers.
The fix: return Promise.all(words.map(async (word) => word.length)); (or drop async: words.map((word) => word.length))
Remember: Promise.all turns a list of promises into a list of results.
The pattern behind it: async and race conditions.
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<iframe src="https://trybughunt.com/embed/001804b0-a37d-4b65-ad16-c5edd86e0e0d" title="Debugging challenge: Word lengths come back as promises, not numbers" width="100%" height="580" loading="lazy" style="border:1px solid #d4d4d8;border-radius:12px;max-width:760px"></iframe>
<p style="font-size:14px">Debugging challenge from <a href="https://trybughunt.com/challenges/001804b0-a37d-4b65-ad16-c5edd86e0e0d">TryBugHunt</a></p>