Apply suggestions from code review

Co-authored-by: Wes Hinsley <[email protected]>

R/packer-grouped.R

@@ -50,7 +50,7 @@
 ##'   are shared among all groups.
 ##'
 ##' @param process An arbitrary R function that will be passed the
-##'   final assembled list **for each region**; it may create any
+##'   final assembled list **for each group**; it may create any
 ##'   *additional* entries, which will be concatenated onto the
 ##'   original list.  If you use this you should take care not to
 ##'   return any values with the same names as entries listed in

tests/testthat/test-packer-grouped.R

@@ -232,7 +232,17 @@ test_that("Can print a grouped packer", {
 })
 
 
-test_that("can used process with grouped packer", {
+test_that("process can't duplicate existing var with grouped packer", {
+  process <- function(res) {
+    list(x = res$x + res$y)
+  }
+  expect_error(
+    monty_packer_grouped(c("a", "b"), c("x", "y"), process = process),
+    "'process\\(\\)' is trying to overwrite")
+})
+
+
+test_that("can use process with grouped packer", {
   process <- function(res) {
     list(z = res$x + res$y)
   }
@@ -243,7 +253,7 @@ test_that("can used process with grouped packer", {
 })
 
 
-test_that("can used process with grouped packer", {
+test_that("can use process with grouped packer", {
   expect_error(
     monty_packer_grouped(c("a", "b"), c("x", "y"), process = TRUE),
     "Expected a function for 'process'")