Posted on Wednesday, 2nd January 2019
Have you ever needed to skip a test under a certain condition? Say, the presence or absence of an environmental variable, or some conditional runtime check? No, me neither - that was up until recently.
Skipping tests is usually a good practice to get into, but I use the word “usually” here because as with all things in software there sometimes certain constraints or parameters that may well justify doing so. In my case I needed to skip a certain test if I was running on AppVeyor in Linux.
Having done a bit of digging I found two options that would work:
Option 1 - Using the
#if
preprocessor directive
Depending on your scenario it might be possible to simple use an
#if
preprocessor directive to include the test. If you’re wishing to exclude a test based on the operating system the test were running on then this may be a solution.
My scenario also involved checking the presence of environmental variables, which I’d rather do through code. This led me to the next approach which I felt was more suitable.
Preferred Option - Leveraging existing XUnit functionality
XUnit already has the ability to skip a test by providing a reason for skipping the test in question via the
Skip
property that exists within the
Fact
attribute:
So all we have to do is extend the
FactAttribute
class and set that property:
Now instead of using the traditional
[Fact]
attribute, we can use our new
IgnoreOnAppVeyorLinuxFact
attribute:
