GH-46636: [R] Fix evaluation of external objects not in global environment in case_when()

r/NEWS.md

@@ -24,6 +24,8 @@
 - Added bindings for atan, sinh, cosh, tanh, asinh, acosh, and tanh, and expm1 (#44953)
 - Expose an option `check_directory_existence_before_creation` in `S3FileSystem`
   to reduce I/O calls on cloud storage (@HaochengLIU, #41998)
+- `case_when()` now correctly detects objects that are not in the global 
+  environment (@etiennebacher, #46667).
 
 # arrow 20.0.0.1
 

r/R/dplyr-eval.R

@@ -30,7 +30,7 @@ arrow_eval <- function(expr, mask) {
   #   regular dplyr may work
   # * validation_error: the expression is known to be not valid, so don't
   #   recommend retrying with regular dplyr
-  tryCatch(eval_tidy(expr, mask), error = function(e) {
+  tryCatch(eval_tidy(expr, mask, env = mask), error = function(e) {
     # Inspect why the expression failed, and add the expr as the `call`
     # for better error messages
     msg <- conditionMessage(e)

r/tests/testthat/test-dplyr-funcs-conditional.R

@@ -491,3 +491,20 @@ test_that("coalesce()", {
     class = "validation_error"
   )
 })
+
+test_that("external objects are found when they're not in the global environment, #46636", {
+  dat <- arrow_table(x = c("a", "b"))
+  pattern <- "a"
+  expect_identical(
+    dat %>%
+      mutate(x2 = case_when(x == pattern ~ "foo")) %>%
+      collect(),
+    tibble(x = c("a", "b"), x2 = c("foo", NA))
+  )
+  expect_identical(
+    dat %>%
+      mutate(x2 = if_else(x == pattern, "foo", NA_character_)) %>%
+      collect(),
+    tibble(x = c("a", "b"), x2 = c("foo", NA))
+  )
+})