tests/testthat/test-verb-arrange.R

In tidyverse/dbplyr: A 'dplyr' Back End for Databases

test_that("two arranges equivalent to one", {
  skip("not clear whether test makes sense")
  mf <- memdb_frame(x = c(2, 2, 1), y = c(1, -1, 1))

  mf1 <- mf %>% arrange(x, y)
  mf2 <- mf %>% arrange(y) %>% arrange(x)

  expect_warning(compare_tbl(mf1, mf2))
})

# sql_render --------------------------------------------------------------

test_that("quoting for rendering ordered grouped table", {
  db <- copy_to_test("sqlite", tibble(x = 1, y = 2), name = "test-verb-arrange")
  out <- db %>% group_by(x) %>% arrange(y) %>% ungroup()
  expect_snapshot(sql_render(out))
  expect_equal(collect(out), tibble(x = 1, y = 2))
})

test_that("arrange renders correctly (#373)", {
  expect_snapshot({
    "# arrange renders correctly"
    lf <- lazy_frame(a = 1:3, b = 3:1)

    "basic"
    lf %>% arrange(a)

    "double arrange"
    lf %>% arrange(a) %>% arrange(b)

    "remove ordered by"
    lf %>% arrange(a) %>% select(-a)
    lf %>% arrange(a) %>% select(-a) %>% arrange(b)

    "un-arrange"
    lf %>% arrange(a) %>% arrange()
    lf %>% arrange(a) %>% select(-a) %>% arrange()

    "use order"
    lf %>% arrange(a) %>% select(-a) %>% mutate(c = lag(b))
  })
})

test_that("arrange renders correctly for single-table verbs (#373)", {
  expect_snapshot({
    lf <- lazy_frame(a = 1:3, b = 3:1)

    "head"
    lf %>% head(1) %>% arrange(a)
    lf %>% arrange(a) %>% head(1)
    lf %>% arrange(a) %>% head(1) %>% arrange(b)

    "mutate"
    lf %>% mutate(a = b) %>% arrange(a)

    "complex mutate"
    lf %>% arrange(a) %>% mutate(a = b) %>% arrange(a)
    lf %>% arrange(a) %>% mutate(a = 1) %>% arrange(b)
    lf %>% mutate(a = -a) %>% arrange(a) %>% mutate(a = -a)
  })
})

test_that("can combine arrange with dual table verbs", {
  expect_snapshot({
    lf <- lazy_frame(a = 1:3, b = 3:1)
    rf <- lazy_frame(a = 1:3, c = 4:6)

    "warn if arrange before join"
    lf %>% arrange(a) %>% left_join(rf)
    lf %>% arrange(a) %>% semi_join(rf)
    lf %>% arrange(a) %>% union(rf)

    "can arrange after join"
    lf %>% left_join(rf) %>% arrange(a)
    lf %>% semi_join(rf) %>% arrange(a)
    lf %>% union(rf) %>% arrange(a)
  })
})

test_that("only add step if necessary", {
  lf <- lazy_frame(x = 1:3, y = 1:3)
  expect_equal(lf %>% arrange(), lf)
})

# sql_build ---------------------------------------------------------------

test_that("arrange generates order_by", {
  out <- lazy_frame(x = 1, y = 1) %>%
    arrange(x) %>%
    sql_build()

  expect_equal(out$order_by, sql('`x`'))
})

test_that("arrange converts desc", {
  out <- lazy_frame(x = 1, y = 1) %>%
    arrange(desc(x)) %>%
    sql_build()

  expect_equal(out$order_by, sql('`x` DESC'))
})

test_that("grouped arrange doesn't order by groups", {
  out <- lazy_frame(x = 1, y = 1) %>%
    group_by(x) %>%
    arrange(y) %>%
    sql_build()

  expect_equal(out$order_by, sql('`y`'))
})

test_that("grouped arrange order by groups when .by_group  is set to TRUE", {
  lf <- lazy_frame(x = 1, y = 1, con = simulate_dbi())
  out <- lf %>%
    group_by(x) %>%
    arrange(y, .by_group = TRUE) %>%
    sql_build()
  expect_equal(out$order_by, sql(c('`x`','`y`')))
})

# ops ---------------------------------------------------------------------

test_that("arranges captures DESC", {
  out <- lazy_frame(x = 1:3, y = 3:1) %>% arrange(desc(x))

  sort <- lapply(op_sort(out), get_expr)
  expect_equal(sort, list(quote(desc(x))))
})

test_that("multiple arranges combine", {
  skip("not clear whether test makes sense")
  out <- lazy_frame(x = 1:3, y = 3:1) %>% arrange(x) %>% arrange(y)
  out <- arrange(arrange(lazy_frame(x = 1:3, y = 3:1), x), y)

  sort <- lapply(op_sort(out), get_expr)
  expect_equal(sort, list(quote(x), quote(y)))
})