test_that("rbind.ddf_col() and rbind.tbl_ddf() work", {
  tbl_ddf1 <- dibble(
    x = 1:12,
    y = 13:24,
    .dim_names = list(axis1 = 1:4, axis2 = 1:3)
  )
  tbl_ddf2 <- dibble(
    x = 1:12,
    y = 13:24,
    .dim_names = list(axis1 = 5:8, axis2 = 4:6)
  )
  expect_error(rbind(tbl_ddf1, tbl_ddf1))

  tbl_ddf3 <- broadcast(
    rbind(tbl_ddf1, tbl_ddf2),
    dim_names = c("axis1", "axis2")
  )
  expect_equal(
    dimnames(tbl_ddf3)[["axis1"]],
    vec_c(dimnames(tbl_ddf1)[["axis1"]], dimnames(tbl_ddf2)[["axis1"]])
  )
  expect_equal(
    tbl_ddf3 |>
      filter(
        axis1 %in% dimnames(tbl_ddf2)[["axis1"]],
        axis2 %in% dimnames(tbl_ddf2)[["axis2"]]
      ),
    tbl_ddf2
  )

  ddf_col1 <- tbl_ddf1[[1]]
  ddf_col2 <- tbl_ddf2[[1]]

  expect_error(rbind(ddf_col1, ddf_col1))

  ddf_col3 <- broadcast(
    rbind(ddf_col1, ddf_col2),
    dim_names = c("axis1", "axis2")
  )
  expect_equal(
    dimnames(ddf_col3)[["axis1"]],
    vec_c(dimnames(ddf_col1)[["axis1"]], dimnames(ddf_col2)[["axis1"]])
  )
  expect_equal(
    ddf_col3 |>
      filter(
        axis1 %in% dimnames(ddf_col2)[["axis1"]],
        axis2 %in% dimnames(ddf_col2)[["axis2"]]
      ),
    ddf_col2
  )

  # works when the number of key rows is 1 (#23)
  data_1 <- tidyr::expand_grid(key = tibble::tibble(col_1 = 1, col_2 = 1)) |>
    tibble::add_column(value = 1) |>
    dibble_by("key")

  data_2 <- tidyr::expand_grid(
    key = tibble::tibble(col_1 = 2:3, col_2 = 2:3)
  ) |>
    tibble::add_column(value = 2) |>
    dibble_by("key")

  data_3 <- tidyr::expand_grid(key = tibble::tibble(col_1 = 2, col_2 = 2)) |>
    tibble::add_column(value = 2) |>
    dibble_by("key")

  data_4 <- tidyr::expand_grid(
    key = tibble::tibble(col_1 = 2, col_2 = 2),
    key_2 = tibble::tibble(col_1 = 2)
  ) |>
    tibble::add_column(value = 2) |>
    dibble_by("key", "key_2")

  expect_no_error(broadcast(rbind(data_1, data_2), "key"))
  expect_no_error(broadcast(rbind(data_1, data_3), "key"))
  expect_no_error(broadcast(rbind(data_1, data_4), c("key", "key_2")))
})