Category Archives: google testing blog

Is Your Interface Two-Faced?

CS SERIES (11).pngWhen coding, users always have to be conscious about the way their code may be implemented or used in the future by different services leading to potential misuse. After reading Code Health: Make Interfaces Hard to Misuse by Marek Kiszkis, it made me think about how important communication between testing code is.

I found this content useful because Kiszkis featured some examples that can show how an interface could be misused easily. The examples included:

  • Requiring callers to call an initialization function
  • Requiring callers to perform custom cleanup
  • Allowing code paths that create objects without required parameters
  • Allowing parameters for which only some values are valid, especially if it is possible to use a more appropriate type

Sam CS (17)It is also good to remember that at the end of the day, code should be defensive but not too defensive to the point that complexity is increased and performance overall is reduced. Kiszkis says “it is not always practical to have a foolproof interface” because there will be situations where some requirements are things that cannot be expressed in an interface.

After seeing so much content based on being careful about what you code it is surprising how this article says it is not necessary to plan too hard. I kind of understand why Kiszkis would say this but personally, I kind of disagree with this. The reason why I disagree is because if someone does happen to end up with more time to work on something than expected and they know it will make something more efficient, then why not go for it?

Overall, I appreciated what was shared in this article in terms of encouraging users to try and see issues that can arise with their code when it comes to interfaces. The main takeaway for me is that if something is brought up, or triggered by undefined behavior, a user should try and make it impossible for this to happen. A way of doing so is by adding things where necessary, like certain slots in his example. It does not have to be too specific but detailed enough so that it covers different aspects, similar to how we try to prepare for everything when it comes to equivalence class testing.


Article: https://testing.googleblog.com/2018/07/code-health-make-interfaces-hard-to.html

 

From the blog CS@Worcester by samanthatran and used with permission of the author. All other rights reserved by the author.