test_that("is_testthat", {
  expect_snapshot(is_testthat)

  testthat_path <- normalizePath("package/tests/testthat", winslash = "/")
  expect_equal(is_testthat$find_file(path = "package"), testthat_path)
  expect_equal(is_testthat$find_file(path = "package/tests"), testthat_path)
  expect_equal(is_testthat$find_file(path = "package/tests/testthat"), testthat_path)
})

test_that("dogfood", {
  expect_true(file.exists(is_testthat$find_file("hierarchy", "a", "b", "c", "d")))
})