Sad name conflict between devtools::test_file() and test that::test_file()

[jennybc]

It's easy for testthat::test_file() to mask devtools::test_file() and I generally want the latter, because file = find_active_file(), i.e. it can determine which test file I mean, if I follow the naming convention.

I had this problem because I attached testthat in ~/.Rprofile, after devtools. But even if I remove that, the problem still recurs because load_all() essentially does the same.

Using devtools' addin is one sure way to get devtools::test_file().

Could the devtools version be renamed or aliased to something that designs this problem away? test_this() perhaps?