tests/testthat/test_usedFactorLevels.R

In jakobbossek/JBmisc: Different tiny helper functions for R.

context("usedFactorLevels")

test_that("usedFactorLevels returns in fact the currently used factor levels", {
  used.levels = letters[1:3]
  all.levels = letters
  x = factor(x = used.levels, levels = all.levels)
  expect_equal(sort(usedFactorLevels(x)), used.levels)

  x = factor(x = used.levels)
  expect_equal(used.levels, levels(x))
})