throw error instead

Author: teunbrand

R/fortify-map.R

@@ -88,7 +88,11 @@ map_data <- function(map, region = ".", exact = FALSE, ...) {
   map_obj <- maps::map(map, region, exact = exact, plot = FALSE, fill = TRUE, ...)
 
   if (!inherits(map_obj, "map")) {
-    return(fortify(map_obj))
+    cli::cli_abort(c(
+      "{.fn maps::map} must return an object of type {.cls map}, not \\
+      {obj_type_friendly(map_obj)}.",
+      i = "Did you pass the right arguments?"
+    ))
   }
 
   df <- data_frame0(

tests/testthat/_snaps/geom-map.md

@@ -6,3 +6,12 @@
 
     `map` must have the columns `x`, `y`, and `id`.
 
+# map_data() checks it input
+
+    Code
+      map_data("world", namesonly = TRUE)
+    Condition
+      Error in `map_data()`:
+      ! `maps::map()` must return an object of type <map>, not a character vector.
+      i Did you pass the right arguments?
+

tests/testthat/test-geom-map.R

@@ -2,3 +2,8 @@ test_that("geom_map() checks its input", {
   expect_snapshot_error(geom_map(map = letters))
   expect_snapshot_error(geom_map(map = mtcars))
 })
+
+test_that("map_data() checks it input", {
+  skip_if_not_installed("maps")
+  expect_snapshot(map_data("world", namesonly = TRUE), error = TRUE)
+})