tests/testthat/test-as-coordinates.R

In tidyterra: 'tidyverse' Methods and 'ggplot2' Helpers for 'terra' Objects

test_that("as_coordinates errors", {
  skip_on_cran()
  v <- volcano
  expect_snapshot(as_coordinates(v), error = TRUE)
})

test_that("as_coordinates return a skeleton", {
  skip_on_cran()
  v <- volcano

  r <- terra::rast(t(v))

  df <- as_coordinates(r)

  expect_s3_class(df, "tbl")
  expect_true(all(
    names(df) ==
      c(
        "cellindex",
        "rowindex",
        "colindex"
      )
  ))

  expect_true(nrow(df) == terra::ncell(r))
  expect_true(ncol(df) == 3)

  expect_equal(
    unique(sort(df$rowindex)),
    seq_len(terra::nrow(r))
  )

  expect_equal(
    unique(sort(df$colindex)),
    seq_len(terra::ncol(r))
  )

  expect_equal(
    df$cellindex,
    seq_len(terra::ncell(r))
  )
})

test_that("as_coordinates return a raster", {
  skip_on_cran()
  v <- volcano
  r <- terra::rast(t(v))

  a_rast <- as_coordinates(r, as.raster = TRUE)

  expect_s4_class(a_rast, "SpatRaster")

  expect_true(compare_spatrasters(r, a_rast))

  # With crs
  r_crs <- r

  terra::crs(r_crs) <- pull_crs("EPSG:3857")

  a_rast_crs <- as_coordinates(r_crs, as.raster = TRUE)

  expect_s4_class(a_rast_crs, "SpatRaster")
  expect_true(compare_spatrasters(r_crs, a_rast_crs))
})