add first test for measurements

tests/testthat/test_measurements.R

@@ -0,0 +1,25 @@
+context("measurements")
+
+check_api <- function() {
+  code <- NA
+  try(code <- httr::status_code(httr::GET(osem_endpoint())))
+  if (is.na(code)) skip("API not available")
+}
+
+try({
+  boxes <- osem_boxes()
+ })
+
+test_that("measurements of specific boxes can be retrieved for one phenomenon and returns a measurements data.frame", {
+  check_api()
+  
+  # fix for subsetting
+  class(boxes) <- c("data.frame")
+  three_boxes <- boxes[1:3,]
+  three_boxes <- osem_as_sensebox(three_boxes)
+  phens <- names(osem_phenomena(three_boxes))
+  
+  measurements <- osem_measurements(x = three_boxes, phenomenon = phens[[1]])
+  expect_true(is.data.frame(measurements))
+  expect_true("osem_measurements" %in% class(measurements))
+})