test_that("verify correct result for complete homogeneity", {
  x <- rep(c("a", "b", "c", "d", "e"), 200)
  H <- ShannonHomogeneity(x)
  expect_equal(H, 1)
})
test_that("verify correct result for intermediate homogeneity", {
  y <- c(rep("a", 497), rep("b", 497), rep("c", 2),
         rep("d", 2), rep("e", 2))
  H <- ShannonHomogeneity(y)
  expect_equal(H, 0.455)
})
test_that("verify correct result for strong heterogeneity", {
  z <- c(rep("a", 996), "b", "c", "d", "e")
  H <- ShannonHomogeneity(z)
  expect_equal(H, 0.02)
})