tests/testthat/test-group_by.R

In privefl/bigdfr: Operate with Data Frames Stored on Disk

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context("test-group_by.R")

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test_that("group_by() works", {

  test <- FDF(iris <- datasets::iris)
  test2 <- group_by(test, Species)
  expect_s3_class(test$groups, "tbl_df")
  expect_equal(dim(test$groups), c(1, 1))
  expect_identical(test2$groups,
                   dplyr::tibble(Species = unique(iris$Species),
                                 ind_row = list(0:49, 50:99, 100:149)))
  expect_identical(dim(group_by(test2, Petal.Length)$groups),
                   c(length(unique(iris$Petal.Length)), 2L))

  test <- FDF(mtcars <- datasets::mtcars)
  test2 <- group_by(test, cyl, vs, am)
  expect_s3_class(test$groups, "tbl_df")
  expect_equal(dim(test$groups), c(1, 1))
  groups_save <- mutate(mtcars, id = 1:n() - 1L) %>%
    group_by(cyl, vs, am) %>%
    dplyr::summarise(ind_row = list(id)) %>%
    dplyr::ungroup()
  expect_identical(test2$groups, groups_save)
  expect_identical(test %>%
                     group_by(cyl, add = TRUE) %>%
                     group_by(vs, add = TRUE) %>%
                     group_by(am, add = TRUE) %>%
                     .$groups, groups_save)

  iris$Petal.Width[1:2] <- c(NA, NaN)
  expect_identical(
    FDF(iris) %>% group_by(Petal.Width) %>% summarise(mean(Sepal.Length)),
    group_by(iris, Petal.Width) %>% summarise(mean(Sepal.Length)))

  expect_s4_class(dplyr::group_by(test, cyl, vs, am), "FDF")
})

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test_that("all verbs works with group_by()", {

  test <- FDF(datasets::iris) %>% filter_int(sample(150))
  test2 <- group_by(test, Species)
  grouped_iris <- as_tibble(test2)
  # as_tibble() also exports groups (version {dplyr})
  expect_identical(grouped_iris, group_by(as_tibble(test), Species))
  # pull() doesn't care about groups
  expect_identical(pull(test2, Species), pull(grouped_iris, Species))
  # summarize() computes by groups
  expect_identical(summarise(test2, mean(Petal.Length)),
                   summarise(grouped_iris, mean(Petal.Length)))
  # filter()
  ind <- sample(150, 50)
  expect_identical(as_tibble(filter_int(test2, ind)), grouped_iris[ind, ])
  expect_equal( ## TODO: Make that identical
    as_tibble(filter(test2, Species == "virginica", Sepal.Length < 5)),
    filter(grouped_iris, Species == "virginica", Sepal.Length < 5))
  # arrange()
  expect_identical(
    as_tibble(arrange(test2, Species, desc(Sepal.Length))),
    arrange(grouped_iris, Species, desc(Sepal.Length)))
  expect_identical(
    as_tibble(arrange(test2, Species, desc(Sepal.Length), .by_group = TRUE)),
    arrange(grouped_iris, Species, desc(Sepal.Length), .by_group = TRUE))
  # mutate()
  expect_identical(
    as_tibble(mutate(test2, rank(Sepal.Width))),
    mutate(grouped_iris, rank(Sepal.Width)))
})

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