test_that("insert_blank_line works as expected", {
  ADSL <- ex_adsl

  lyt <- basic_table() |>
    split_cols_by("ARM") |>
    split_rows_by("STRATA1") |>
    analyze(vars = "AGE", afun = function(x) {
      in_rows(
        "Mean (sd)" = rcell(c(mean(x), sd(x)), format = "xx.xx (xx.xx)")
      )
    }) |>
    insert_blank_line() |>
    analyze(vars = "AGE", table_names = "AGE_Range", afun = function(x) {
      in_rows(
        "Range" = rcell(range(x), format = "xx.xx - xx.xx")
      )
    }) |>
    insert_blank_line() |>
    analyze(vars = "AGE", table_names = "AGE_Median", afun = function(x) {
      in_rows(
        "Median" = rcell(median(x), format = "xx.xx")
      )
    })

  # We don't want to see any warning about duplicate table names here.
  tbl <- expect_silent(build_table(lyt, ADSL))
  tbl

  # We expect 6 blank lines: after mean and range, for each of the
  # 3 STRATA1 levels' row splits.
  expect_snapshot(mf_strings(matrix_form(tbl)))
})

test_that("insert_blank_line optionally uses custom table names", {
  ADSL <- ex_adsl

  lyt <- basic_table() |>
    split_cols_by("ARM") |>
    split_rows_by("STRATA1") |>
    analyze(vars = "AGE", afun = function(x) {
      in_rows(
        "Mean (sd)" = rcell(c(mean(x), sd(x)), format = "xx.xx (xx.xx)")
      )
    }) |>
    insert_blank_line(table_names = "Gap1") |>
    analyze(vars = "AGE", table_names = "AGE_Range", afun = function(x) {
      in_rows(
        "Range" = rcell(range(x), format = "xx.xx - xx.xx")
      )
    }) |>
    insert_blank_line(table_names = "Gap2") |>
    analyze(vars = "AGE", table_names = "AGE_Median", afun = function(x) {
      in_rows(
        "Median" = rcell(median(x), format = "xx.xx")
      )
    })

  # We don't want to see any warning about duplicate table names here.
  tbl <- expect_silent(build_table(lyt, ADSL))
  tbl

  # We expect 6 blank lines: after mean and range, for each of the
  # 3 STRATA1 levels' row splits.
  tbl_string <- mf_strings(matrix_form(tbl))
  tbl_row_paths <- row_paths(tbl)
  for (row in c(5, 8, 14, 17, 23, 26)) {
    expect_identical(tbl_string[row, ], rep("", length = 4))
  }
  for (row in c(4, 13, 22)) {
    checkmate::expect_subset("Gap1", tbl_row_paths[[row]])
  }
  for (row in c(7, 16, 25)) {
    checkmate::expect_subset("Gap2", tbl_row_paths[[row]])
  }
})