Use the following steps to build a unit test suite to ensure that functions work as you intend:

1. Create the test folder structure:

usethis::use_testthat()

2. Add a new test:

usethis::use_test("adds")

test_that("addition works", {
 expect_equal(1 + 1, 2)
})

3. Run the actual tests:

devtools::test()