Merge pull request epiforecasts#451 from epiforecasts/RichardMN-test-…

…json-2

Add tests for json_reader function and sample json data

NAMESPACE

@@ -41,6 +41,7 @@ export(start_using_memoise)
 export(stop_using_memoise)
 export(test_cleaning)
 export(test_download)
+export(test_download_JSON)
 export(test_processing)
 export(test_return)
 importFrom(R6,R6Class)
@@ -75,6 +76,7 @@ importFrom(dplyr,pull)
 importFrom(dplyr,recode)
 importFrom(dplyr,rename)
 importFrom(dplyr,select)
+importFrom(dplyr,slice_head)
 importFrom(dplyr,slice_tail)
 importFrom(dplyr,starts_with)
 importFrom(dplyr,summarise)

NEWS.md

@@ -12,6 +12,7 @@ This release is currently under development
 * Change the data source for Switzerland to draw data from the Swiss Federal Office of Public Health (FOPH)
 * Updated the package logo to include the newly supported data sets.
 * Reduced the number of package dependencies (@bisaloo and @RichardMN)
+* Added tests for JSON download code (@RichardMN).
 
 ## Bug fixes
 

R/test-DataClass.R

@@ -121,6 +121,47 @@ test_download <- function(DataClass_obj, download, snapshot_path) {
   }
 }
 
+
+#' Test download method for JSON files works correctly
+#' @description Test data can be downloaded if `download = TRUE`, or a requested
+#' snapshot file is not found, and store a snap shot in the `snapshot_dir`. If
+#' an existing snapshot file is found then load this data to use in future tests
+#' @param DataClass_obj The R6Class object to perform checks on.
+#' Must be a `DataClass` or `DataClass` child object.
+#' @param download Logical check to download or use a snapshot of the data
+#' @param snapshot_path character_array the path to save the downloaded
+#' snapshot to.
+#' @importFrom purrr map walk
+#' @importFrom dplyr slice_head
+#' @family tests
+#' @concept tests
+#' @export
+test_download_JSON <- function(DataClass_obj, download, snapshot_path) {
+  if (!file.exists(snapshot_path)) {
+    download <- TRUE
+  }
+  if (download) {
+    testthat::test_that(
+      paste0(DataClass_obj$data_name, " downloads sucessfully"),
+      {
+        DataClass_obj$download_JSON()
+        walk(DataClass_obj$data$raw, function(data) {
+          testthat::expect_true(length(data) > 0)
+          testthat::expect_false(is.null(data))
+        })
+      }
+    )
+    DataClass_obj$data$raw <- map(DataClass_obj$data$raw,
+    slice_head,
+    n = 2
+    )
+
+    saveRDS(DataClass_obj$data$raw, snapshot_path)
+  } else {
+    DataClass_obj$data$raw <- readRDS(snapshot_path)
+  }
+}
+
 #' Test clean method works correctly
 #' @description Test data can be cleaned properly. The clean method is invoked
 #' to generate clean data. This data is checked to ensure it is a data.frame,

tests/testthat/custom_data/mtcars.json

@@ -0,0 +1 @@
+[{"mpg":21,"cyl":6,"disp":160,"hp":110,"drat":3.9,"wt":2.62,"qsec":16.46,"vs":0,"am":1,"gear":4,"carb":4},{"mpg":21,"cyl":6,"disp":160,"hp":110,"drat":3.9,"wt":2.875,"qsec":17.02,"vs":0,"am":1,"gear":4,"carb":4},{"mpg":22.8,"cyl":4,"disp":108,"hp":93,"drat":3.85,"wt":2.32,"qsec":18.61,"vs":1,"am":1,"gear":4,"carb":1},{"mpg":21.4,"cyl":6,"disp":258,"hp":110,"drat":3.08,"wt":3.215,"qsec":19.44,"vs":1,"am":0,"gear":3,"carb":1},{"mpg":18.7,"cyl":8,"disp":360,"hp":175,"drat":3.15,"wt":3.44,"qsec":17.02,"vs":0,"am":0,"gear":3,"carb":2},{"mpg":18.1,"cyl":6,"disp":225,"hp":105,"drat":2.76,"wt":3.46,"qsec":20.22,"vs":1,"am":0,"gear":3,"carb":1}]

tests/testthat/test-json_reader.R

@@ -0,0 +1,36 @@
+test_path <- "custom_data/mtcars.json"
+target <- tibble::as_tibble(head(mtcars))
+
+test_that("json_reader can read in a simple dataset", {
+  test <- json_reader(test_path)
+  expect_s3_class(test, "tbl_df")
+  expect_equal(
+    colnames(test),
+    colnames(target)
+  )
+  attributes(test)$spec <- NULL
+  attributes(test)$problems <- NULL
+  expect_equal(
+    test,
+    target
+  )
+})
+
+test_that("json_reader verbosity is controlled as expected", {
+  expect_gte(
+    length(capture.output(tmp <- json_reader(test_path, verbose = TRUE),
+      type = "message"
+    )),
+    1
+  )
+  expect_equal(
+    length(capture.output(tmp <- json_reader(test_path, verbose = FALSE),
+      type = "message"
+    )),
+    0
+  )
+})
+
+test_that("json_reader fails as expected when given a file that doesn't exist", {
+  expect_error(json_reader("nonsense.json", verbose = FALSE))
+})