alt Hacker NewsSome times there is, and in many cases there is not. Distinguishing a feature from a bug requires having some kind of spec. In some cases you can have obvious sign the behaviour is unintended/not desired, but in other cases it's not so easy.
For example a customer reports a bug, your program can't print. Oh, you say, we never even had that feature! Please post again, as a feature request.
Customer mumbles and requests the same thing as a feature request, not a bug report. They never understood what the difference was though. They couldn't print. Program bad.
Now you implement the printing feature. There is an infinity of things to handle there. You add the 99.9% case which is basically regular printers, perhaps normal paper sizes. You however don't throw in things like document splitting (sending different pages to different devices based on capability). You have to stop somewhere. None of this is specified, however. None of the limitations are communicated to users. But you added the feature - in some sense. Then a customer with a 1970's pen plotter files a bug report that your new feature doesn't work on his device. Will you fix his bug? He's the only one on the planet with the problem. Is it a bug or a new feature? To him it's _clearly_ a bug. To you it would _clearly_ be a new feature to support pen plotting. You could argue the semantics of whether this is a bug or a feature until the sun goes down and it doesn't really matter. Either the fixed bug/added feature has enough value to be done, or it doesn't.
A key takeaway here: this isn't merely something that appears in the perspective of the user vs the developer. The argument about whether you actually have a "Bug" because you stopped short of implementing every kind of printing known to man is one you could have with your PM too. He likely didn't even consider that. But does that make it not a bug?
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>Some times there is, and in many cases there is not. Distinguishing a feature from a bug requires having some kind of spec. In some cases you can have obvious sign the behaviour is unintended/not desired, but in other cases it's not so easy. For example a customer reports a bug, your program can't print. Oh, you say, we never even had that feature! Please post again, as a feature request.Customer mumbles and requests the same thing as a feature request, not a bug report. They never understood what the difference was though. They couldn't print. Program bad.
Any software has a spec. It might not be publicly written, but you have in mind what you build and which features it supports. And software that's sold has lists of features, presentation pages, and trials for people to see its features.
If some random user can't tell a bug from a feature, that's on them.
> For example a customer reports a bug, your program can't print. Oh, you say, we never even had that feature! Please post again, as a feature request.
As a sidenote, I dislike it when a vendor makes me care whether something is a bug report, feature request, or support query prior to filing it. I'm willing to make an assessment on whether the query is of a public or private (if I'm unwilling to publish publicly, sensitive customer info, potential for vuln et c.) nature but beyond that I don't want to spend any time arguing about classification.
An unuseful-in-99%-of-cases definition of bug would be "any behavior that is not in the spec is a bug". But that would mean not shipping fast and breaking things. And having a spec.
There is a pretty clear and important difference between a program that does something wrong, and a program that just doesn't do something somebody wants.
"You don't support printing", "pressing the print button doesn't print", "pressing the print button crashes the computer" and "pressing the print button lets an attacker get root access to the system" are all different and it makes sense to distinguish them. (The first is a missing feature, the second and third are different kinds of bugs, the last is a special kind of bug we call a security vulnerability.)
That distinction might not be useful to end-users, but it's useful for the people building the system! If you want to care about quality, committing to a strategy like "we will not add features before we fix known bugs" is totally clear, reasonable and effective. There might be some frontier of issues where it's hard to make a distinction, but that just means there are subtle edge-cases, not that the whole concept is undefined. A lot of perfectly cromulent concepts have edge-cases! You can just decide those on a case-by-case basis; if it's actually so close as to be legitimately confusing—it's not just feigned ignorance or political posturing—which side you choose probably doesn't have much of an effect.
This does depend on having a reasonably clear idea of what you're building, but that "reasonably clear idea" does not have to be anywhere near the detail of a "full spec", much less anything formalized. To me, that seems like a baseline you'd need to build quality software at all, and hardly an unreasonable thing to expect. And if most teams can't manage, well, it's just another explanation for why most software is crap.