test_that("se_summarise works with one grouping variable", {
  # Sample data
  df <- tibble(
    zone = c("A", "A", "B", "B", "A", "B", "A", "B", "A", "B"),
    weight = c(1.1, 1.4, 2.0, 0.9, 1.6, 2.2, 1.3, 1.8, 1.0, 2.5),
    score = c(10, 12, 9, 11, 8, 14, 7, 13, 10, 15),
    group = c("G1", "G1", "G2", "G2", "G1", "G2", "G1", "G2", "G1", "G2"),
    category = rep(c("X", "Y"), each = 5)
  )

  # Expected output
  expected <- df |>
    group_by(zone) |>
    mutate(mh = n()) |>
    mutate(Nh = sum(weight)) |>
    ungroup() |>
    distinct(zone, mh, Nh) |>
    arrange(zone)

  # Actual result from the function
  result <- se_summarise(df, weight = weight, zone) |>
    distinct(zone, mh, Nh) |>
    arrange(zone)

  expect_equal(result, expected)
})

test_that("se_summarise works with multiple grouping variables", {
  df <- tibble(
    zone = rep(c("A", "B"), each = 5),
    group = rep(c("G1", "G2"), times = 5),
    weight = c(1.161500, 2.668666, 2.201522, 1.314417, 1.014799, 1.932787, 1.995555, 1.579534, 2.465764, 2.545043)
  )

  # Expected output
  expected <- df |>
    group_by(zone, group) |>
    mutate(mh = n()) |>
    mutate(Nh = sum(weight)) |>
    ungroup() |>
    distinct(zone, group, mh, Nh) |>
    arrange(zone)

  # Actual result from the function
  result <- se_summarise(df, weight = weight, zone, group) |>
    distinct(zone, group, mh, Nh) |>
    arrange(zone)
  expect_true(all(c("mh", "Nh") %in% names(result)))
  expect_equal(result, expected)
})