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map returns promises instead of values — JavaScript debugging challenge | BugHunt

javascriptAsync race conditionMedium

map returns promises instead of values

Time: 0:00

What it should do

wordLengths(words) should resolve to a list of each word's length.

What goes wrong

wordLengths(["abc", "defg"]) resolves to [{}, {}] instead of [3, 4].

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Hints

This is an async and race conditions bug

A missing await, results in the wrong order, and updates that overwrite each other under load.

Learn the async and race conditions pattern