context("timestamps")
test_that("timestamps function works", {
  data(leroy)
  expect_equal(timestamps(leroy), leroy@timestamps)
  t <- Sys.time() + 1:n.locs(leroy)
  timestamps(leroy) <- t
  expect_equal(timestamps(leroy), t)
  expect_error(timestamps(leroy)[5:8] <- t[1] + 5:8 + 100)
})