Menu
I've spent lots of time with RSpec and some time with xunit style tests. I've gotten accustom to having mocks and stubbing at my disposal.
Is there anything like mocks or stubbing in R? What frameworks have them?
If not how do you isolate your tests?
453
Mocks verify the behavior of the code you're testing, also known as the system under test. Mocks should be used when you want to test the order in which functions are called. Stubs verify the state of the system under test.
A stub is where you replace an existing implementation of a custom component or directive with a dummy one that doesn't do anything at all, which can simplify an otherwise complex test. Let's see an example.
Mocks and stubs are very handy for unit tests. They help you to test a functionality or implementation independently, while also allowing unit tests to remain efficient and cheap, as we discussed in our previous post.
A stub is a fake class that comes with preprogrammed return values. It's injected into the class under test to give you absolute control over what's being tested as input. A typical stub is a database connection that allows you to mimic any scenario without having a real database.
It wasn't available until 4 years after you asked this question, but it looks like testthat does include a with_mock() function now:
https://github.com/hadley/testthat/blob/master/R/mock.R
Seems to fit the bill pretty well.
99
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With
