Time: 0:00
Test a custom input to verify an edge case (e.g. empty lists, negative numbers, duplicates).
This bug belongs to the null and undefined errors pattern
Cannot read properties of undefined, NoneType has no attribute, NaN appearing from nowhere.
What went wrong: x or 3 uses 3 whenever x counts as false. 0 counts as false, so a real 0 is replaced.
The fix: value = config.get("retries") then return 3 if value is None else value
Remember: 0, "" and [] count as false. Use is None to check for a missing value.
The pattern behind it: null and undefined errors.
Paste this into any web page or blog post. Visitors fix the bug right there, in their browser.
<iframe src="https://trybughunt.com/embed/786da376-2b2f-4f9c-b7ee-0edce4ffc27a" title="Debugging challenge: Setting retries to 0 gives 3 retries" 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/786da376-2b2f-4f9c-b7ee-0edce4ffc27a">TryBugHunt</a></p>