context("ne countries : data saved in package")

spdf_world <- ne_countries()
spdf_africa <- ne_countries(continent = "africa")
spdf_france <- ne_countries(country = "france")

test_that("type of object returned is as expected", {
  expect_is(spdf_world, "SpatialPolygonsDataFrame")
  expect_is(spdf_africa, "SpatialPolygonsDataFrame")
  expect_is(spdf_france, "SpatialPolygonsDataFrame")
})

# not sure whether I want to test num polygons explicitly
# I might want to allow flexibility for these to change as the data changes
test_that("number of rows/polygons in objects is as expected", {
  expect_equal(length(spdf_world), 177)
  expect_equal(length(spdf_africa), 51)
  expect_equal(length(spdf_france), 1)
})

test_that("scale argument gives expected relative sizes of objects", {
  expect_gt(
    object.size(ne_countries(scale = "medium")),
    object.size(ne_countries(scale = "small"))
  )

  expect_gt(
    object.size(ne_countries(scale = 50)),
    object.size(ne_countries(scale = 110))
  )
})

test_that("equivalent scale arguments as numeric or text give identical results", {
  expect_identical(
    ne_countries(scale = "medium"),
    ne_countries(scale = 50)
  )

  expect_identical(
    ne_countries(scale = "small"),
    ne_countries(scale = 110)
  )
})

test_that("Error message if incorrect filters are applied", {
  expect_error(ne_countries(continent = "madeupname"))
  expect_error(ne_countries(country = "madeupname"))
  expect_error(ne_countries(geounit = "madeupname"))
  expect_error(ne_countries(sovereignty = "madeupname"))
})

test_that("Error message if incorrect type argument", {
  expect_error(ne_countries(type = "madeupname"))
})