Time: 0:00
Test a custom input to verify an edge case (e.g. empty lists, negative numbers, duplicates).
This bug belongs to the logic errors pattern
The wrong operator, an inverted condition, a formula the right way round but backwards.
What went wrong: Array.prototype.every() returns true for an empty array (vacuous truth) because no elements violate the condition.
The fix: Explicitly check that items contains at least one element: items.length > 0 && items.every(item => item.inStock)
Remember: In JavaScript, [].every() is always true and [].some() is always false.
The pattern behind it: logic errors.
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<iframe src="https://trybughunt.com/embed/17c32293-614d-4bd6-8347-9ad82f301ab2" title="Debugging challenge: Checking all items in empty cart are in stock returns true" 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/17c32293-614d-4bd6-8347-9ad82f301ab2">TryBugHunt</a></p>