tests/testthat/test_get_crime_data.R

In mpjashby/crimedata: Access Crime Data from the Open Crime Database

context("Test function to get crime data")

test_that("return value of get_crime_data is a tibble or SF object", {
  skip_if_offline()
  expect_is(get_crime_data(cities = "Austin"), "tbl_df")
  expect_is(get_crime_data(cities = "Austin", output = "sf"), "sf")
})

test_that("incorrect arguments produce errors", {

  # Arguments of the wrong type
  expect_error(get_crime_data(type = "blah"))
  expect_error(get_crime_data(years = 2019.5))
  expect_error(get_crime_data(quiet = "blah"))

  # Arguments of the wrong length
  expect_error(get_crime_data(type = character(0)))
  expect_error(get_crime_data(years = integer(0)))
  expect_error(get_crime_data(quiet = logical(0)))

  skip_if_offline()

  # Argument specifying non-existent data
  expect_error(
    get_crime_data(years = 1990:1995),
    "One or more of the requested years"
  )
  expect_error(
    get_crime_data(cities = "non-existant city"),
    "Data is not available for one or more of the specified cities"
  )

  # Data for Virginia Beach are only available from 2013 onwards
  expect_error(
    get_crime_data(cities = "Virginia Beach", years = 2007),
    "The Crime Open Database does not contain data for any"
  )
})

# test_that("partially missing data produce warnings", {
#   skip_if_offline()
#   # 2015 is not present in the data but 2016 is, so this should produce a
#   # warning rather than an error
#   expect_warning(
#     get_crime_data(cities = "Boston", years = 2015:2016),
#     "Data are not available for crimes in"
#   )
# })

test_that("quiet execution does not return any messages", {
  skip_if_offline()
  # Testing for an NA message allows testing for the absence of a message, as
  # per https://stackoverflow.com/q/10826365/8222654
  expect_message(get_crime_data(years = 2019, quiet = TRUE), NA)
})

# test_that("data cache works as expected", {
#
#   skip_if_offline()
#
#   # get data, which should then be cached
#   get_crime_data(cities = "Charlotte")
#
#   # request data again and check if it is retrieved from the cache
#   expect_message(
#     get_crime_data(cities = "Charlotte"),
#     "Loading cached data"
#   )
#
#   # request data again, forcing download from server
#   expect_message(
#     get_crime_data(cities = "Charlotte", cache = FALSE),
#     "Deleting cached data"
#   )
# })