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: When the last item is 0, pop() returns 0. The || -1 operator treats 0 as falsy and returns the fallback -1.
The fix: Check explicitly for undefined: val === undefined ? -1 : val
Remember: In JavaScript, array.pop() returns undefined when empty; 0 is a valid element that should not trigger fallbacks.
The pattern behind it: logic errors.
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<iframe src="https://trybughunt.com/embed/1a4e96d1-f56e-4220-810c-16655f81f461" title="Debugging challenge: Array pop on array with zero element returns fallback value" width="100%" height="580" loading="lazy" style="border:1px solid #d4d4d8;border-radius:12px;max-width:760px"></iframe>
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