JunitReporter fails badly on warning outside of test_that

[pawelru]

Hi! I wanted to share an use case in which JunitReporter throws and others don't.

I had the following (pseudo-code)

new_foo <- \(...) {...}

old_foo <- \(...) {
  lifecycle::deprecate_warn(...)
  new_foo(...)
}

In test file:

x <- old_foo(...)

test_that("foo is working", {
  ...
})

When using JunitReporter and only(!) during check it fails as follows:

  Error in UseMethod("xml_add_child") : 
    no applicable method for 'xml_add_child' applied to an object of class "NULL"
  Calls: test_check ... o_apply -> lapply -> FUN -> <Anonymous> -> <Anonymous>
  Execution halted

This line in particular: https://github.com/r-lib/testthat/blob/07c5cd99c3098b9f228258fe7a3df5a3e9a7a2b8/R/reporter-junit.R#L106-L111

For some reason self$suite is NULL when calling $add_result() method. My guess is it's because it's outside of test_that.

We have addressed this internally by changing x <- old_foo() into x <- new_foo() but I think it would be good to share it with you as this was not a problem for a default reporter (haven't checked all of them) as well as within TEST (as opposed to CHECK).