Tutorial on the types of tests to write for an R function

[jamesmbaazam]

Context

Provides some guidance on how to write tests that cover four categories:

• Normal Cases: Typical input that should follow the main path through the code.
• Opposites: Cases that return opposite outputs (e.g. TRUE and FALSE).
• Large Cases: Typical input, but of a larger size than usual. This ensures that bugs don’t appear after multiple iterations.
• Edge Cases: Pairs of inputs that test different choice points in the code. For example, if a condition in the problem checks whether n < 2, two important edge cases are when n = 2 and n = 3, which trigger different behaviors. Other edge cases include the first / last characters in a string or items in a list.
• Special Cases: Some inputs need to be special-cased for many problems. This includes negative numbers, 0 and 1 for integers, the empty string (""), and input values of different types than are expected.

URL

https://p4a.jhelvy.com/testing-debugging#test-case-types

Suggested labels

Best Practice, Testing, Code coverage