This function creates (or opens) a test helper file, typically
tests/testthat/helper.R. Test helper files are executed at the
beginning of every automated test run and are also executed by
load_all(). A helper file is a great place to
define test helper functions for use throughout your test suite, such as
a custom expectation.
use_test_helper(name = NULL, open = rlang::is_interactive())use_test() to create a test file.
The testthat vignette on special files
vignette("special-files", package = "testthat").
if (FALSE) { # \dontrun{
use_test_helper()
use_test_helper("mocks")
} # }