I thought I would share this small piece of advice. It might be obvious to a lot of people but is not always apparent or sometimes we forget or even run out of time to pay enough attention to it.
The advice is simply this:
When you report a bug or issue and the developer tells you it’s fixed, always check that it is actually fixed.
Sounds obvious doesn’t it?
Think back to times when you have taken the word of the developer that a particular bug has been fixed and decided not to test it or verify that it had actually been completed. Ok, it sounds a bit strong that you knowingly decided not to test the bug fix, you could have been swayed by a couple of factors. Perhaps that developer has always fixed bugs satisfactorily in the past or maybe you didn’t have the time to check the bug had been fixed properly and so gambled that it had been fully dealt with.
Whatever the reasons the result is that the bug fix did not get checked out and verified. For many issues, the fix put in place would simply have worked and that would be the end of the matter. That particular bug would never be heard of again, the gamble paid off.
But what are the chances that the fix did not work, or created a new previously undetected bug or that the developer misinterpreted the bug report and his or her fix is not what you expected. In my experience, the chances of things like this happening are pretty good (website testers are such a pessimistic bunch).
On occasion, bug ‘fixes’ like this actually have a bigger impact on the website than the original bug. They can make the situation worse rather than better. A minor bug that is improperly fixed can have a much bigger effect and without testing and verifying it properly you don’t know if that has happened this time or not.
Fixing A Bug And Making It Worse
To illustrate how it is easy to fix a bug and make it worse, consider the following.
Some work I have been managing recently involved using a fairly simple script. The way the script works is that you send a series of locations to it, in the form of a CSV file, and the script fetches data about each of those locations, which is then uploaded to an email marketing system.
The data that is returned by the script is dropped into personalised emails, which are regularly sent to thousands or even tens of thousands of people at a time.
The script is not the greatest of solutions but it is a fairly quick and straightforward piece of programming, which generally works well.
I reported a bug that for one particular location, no data was being returned by the script. We had to manually add the data for that one location, which was frustrating and time consuming but not the end of the world. A developer investigated the bug and soon after pronounces the issue fixed. The information is relayed to me that the bug is fixed. Everyone rejoices (not really, everyone just gets on with the next job).
When I check the script over, send some location data to it and review the results I find that data is indeed now being returned for the offending location. However, it is the wrong data. There are 2 locations in that particular city and the script is returning data for the other location.
Just to recap, the original bug was that no data was returned by the script for that single location. An inconvenience in that the missing data had to be manually added. The bug ‘fix’ has actually introduced a 2nd bug, which is that the incorrect data is now being returned for that single location, a more significant bug than the previous one if it went unnoticed, as thousands of individuals would have had incorrect personalisation details incorporated into emails they received from the organisation creating a great deal of confusion.
It just goes to show that when someone tells you a bug has been fixed, please always check. Something may indeed have been fixed, just not always what you anticipated. On occasion, the situation may have actually been made worse and not better.
I am sure that there are lots of similar stories to this one where a bug fix did not fix the bug but perhaps made it worse. Feel free to share any in the comments.
Image credit BenSutherland
