test_that("taudem_aread8() works", {
  skip_on_cran()
  withr::local_options(traudem.quiet = TRUE)
  test_dir <- withr::local_tempdir()
  file.copy(
    system.file("test-data", "DEM.tif", package = "traudem"),
    file.path(test_dir, "DEM.tif")
  )
  withr::local_dir(test_dir)
  taudem_pitremove(
    input_elevation_grid = "DEM.tif",
    output_elevation_grid = "DEMfel.tif"
  )

  # D8 flow direction ####
  taudem_d8flowdir(
    input_elevation_grid = "DEMfel.tif",
    output_d8flowdir_grid = "DEMp.tif",
    output_d8slopes_grid = "DEMsd8.tif"
  )

  # D8 contributing area ####
  taudem_aread8(
    input_d8flowdir_grid = "DEMp.tif",
    output_contributing_area_grid = "DEMad8.tif"
  )
  ad8 <- terra::rast("DEMad8.tif")

  expect_equal(max(terra::values(ad8), na.rm = T), 7318)

})