nmTest({
  test_that("test timing engine", {
    skip_on_os("mac")
    env <- new.env(parent=emptyenv())
    env$time <- data.frame(t0=1)

    nlmixrWithTiming("time1", {
      Sys.sleep(0.25)
      # note this can be nested, time1 will exclude the timing from time2
      nlmixrWithTiming("time2", {
        Sys.sleep(0.25)
        nlmixrWithTiming("t0", {
          Sys.sleep(0.1)
        }, envir=env)
      }, envir=env)
    }, envir=env)

    expect_true(env$time$time2 < 0.4)
    expect_true(env$time$time1 < 0.4)
    expect_true(env$time$t0 > 1)

    nlmixrAddTiming(env, "time2", 3)

    expect_true(env$time$time2 > 3)

    nlmixrAddTiming(env, "new", 3.5)

    expect_true(env$time$new > 3)

  })
})