test_that("aggregate_var works", {

  list_iris <-
    list(sepal = c("Sepal.Length", "Sepal.Width"),
         petal = c("Petal.Length", "Petal.Width"),
         c("Sepal.Length", "Sepal.Width", "Petal.Length", "Petal.Width"))

  agg1 <- aggregate_var(iris, list_agg = list_iris, fun_agg = prod,
                        prefix = "group", keep_original_cols = TRUE)

  expect_equal(colnames(agg1),
               c(names(iris), names(list_iris[1:2]), "group3"))
  expect_equal(agg1[, 1:5], iris)
  expect_equal(agg1$sepal, iris$Sepal.Length * iris$Sepal.Width)
  expect_equal(agg1$group3, iris$Sepal.Length * iris$Sepal.Width *
                 iris$Petal.Length * iris$Petal.Width)

  agg2 <- aggregate_var(iris, list_agg = list_iris, fun_agg = prod)

  expect_equal(colnames(agg2), c("Species", names(list_iris[1:2]), "agg_3"))
  expect_equal(agg2$sepal, agg1$sepal)
})