test_that("mockObservationPeriod", {
  expect_no_error(
    cdm <- emptyCdmReference(cdmName = "test") |>
      mockPerson(nPerson = 1000,
                 birthRange = as.Date(c("1990-01-01", "2000-01-01"))) |>
      mockObservationPeriod()
  )
  expect_true(all(colnames(cdm$observation_period) %in%
                    c("observation_period_id", "person_id",
                      "observation_period_start_date",
                      "observation_period_end_date",
                      "period_type_concept_id")))
  expect_equal(cdm$observation_period$person_id,
               cdm$person$person_id)
  expect_true(all(cdm$observation_period$observation_period_start_date <
                    cdm$observation_period$observation_period_end_date))
  expect_true(all(cdm$observation_period$observation_period_id ==
                    cdm$observation_period$person_id))
})