test_that("classes are correct", {
   sad1 <- sim_sad(s_pool = 3L, n_sim = 10L)
   expect_s3_class(sad1, "sad")
   expect_s3_class(sad1, "integer")

   xmother <- lapply(1:length(sad1), function(x) runif(1, 0, 1))
   ymother <- lapply(1:length(sad1), function(x) runif(1, 0, 1))

   expect_s3_class(sim_poisson_coords(sad1), "community")
   expect_s3_class(sim_poisson_community(3L, 10L), "community")
   expect_s3_class(sim_thomas_coords(sad1), "community")
   expect_s3_class(sim_thomas_coords(sad1, mother_points = 0), "community")
   expect_s3_class(sim_thomas_coords(sad1, mother_points = 100), "community")
   expect_s3_class(sim_thomas_coords(sad1, mother_points = 4.2), "community")
   expect_s3_class(sim_thomas_coords(sad1, xmother = xmother, ymother = ymother), "community")
   expect_s3_class(sim_thomas_coords(sad1), "community")
   expect_s3_class(sim_thomas_community(3L, 10L), "community")
   expect_s3_class(community(runif(10L), runif(10L), rep("specA", 10L)), "community")
   expect_s3_class(community_to_sad(sim_poisson_community(3L, 10L)), "sad")
})