Don't write to the test directory during testing

Trees and reference items are copied into a test directory. In certain testing environments, the test directory is not writeable. The only safe location to modify files is within tempdir()

Author: michaelquinn32

R/testing.R

@@ -41,10 +41,11 @@ test_collection <- function(test, sub_test = NULL,
 
   out_names <- construct_out(in_names)
 
-  out_items <- file.path(path, out_names)
   in_items <- file.path(path, in_names)
-
-  out_trees <- construct_tree(in_items)
+  out_items <- file.path(tempdir(), out_names)
+  ref_items <- file.path(path, out_names)
+  file.copy(ref_items, out_items, overwrite = TRUE, copy.mode = FALSE)
+  out_trees <- file.path(tempdir(), construct_tree(in_names))
 
   pwalk(list(in_items, out_items, in_names, out_names, out_trees),
     transform_and_check,