Supply both before_arg and after_arg to error_arg.

Change class of error message

Use new comment.

DESCRIPTION

@@ -39,3 +39,4 @@ Config/Needs/website: tidyverse/tidytemplate
 Config/testthat/edition: 3
 Encoding: UTF-8
 RoxygenNote: 7.3.2
+Roxygen: list(markdown = TRUE)

R/eval-relocate.R

@@ -78,7 +78,6 @@ eval_relocate <- function(expr,
   data <- tidyselect_data_proxy(data)
 
   expr <- as_quosure(expr, env = env)
-
   sel <- eval_select_impl(
     x = data,
     names = names(data),
@@ -89,7 +88,7 @@ eval_relocate <- function(expr,
     allow_empty = allow_empty,
     allow_predicates = allow_predicates,
     type = "relocate",
-    error_arg = NULL, # TODO need to know which to use. can `before_arg` or `after_arg` be passed here?
+    error_arg = c(before_arg, after_arg), 
     error_call = error_call
   )
 

R/eval-select.R

@@ -105,8 +105,8 @@
 #' # Note that the trick above works because `expr({{ arg }})` is the
 #' # same as `enquo(arg)`.
 #'
-#' # give a better error message if you don't want empty selection
-#' # if supplying `error_arg`
+#' # Supply `error_arg` to improve the error message in case of
+#' # unexpected empty selection:
 #' select_not_empty <- function(x, cols) {
 #'   eval_select(expr = enquo(cols), data = x, allow_empty = FALSE, error_arg = "cols")
 #' }
@@ -182,6 +182,7 @@ eval_select_impl <- function(x,
   if (is_null(names)) {
     cli::cli_abort("Can't select within an unnamed vector.", call = error_call)
   }
+
   # Put vars in scope and peek validated vars
   local_vars(names)
   vars <- peek_vars()

R/eval-walk.R

@@ -135,13 +135,13 @@ check_empty <- function(x, allow_empty = TRUE, error_arg = NULL, call = caller_e
       cli::cli_abort(
         "Must select at least one item.",
         call = call,
-        class = "tidyselect:::error_disallowed_empty"
+        class = "tidyselect_error_empty_selection"
       )
     } else {
       cli::cli_abort(
-        "{.or {.arg {error_arg}}} must select at least one column.",
+        "{.arg {error_arg}} must select at least one column.",
         call = call,
-        class = "tidyselect:::error_disallowed_empty"
+        class = "tidyselect_error_empty_selection"
         )
     }
   }

tests/testthat/_snaps/eval-relocate.md

@@ -84,21 +84,36 @@
     Code
       (expect_error(relocate_loc(x, allow_empty = FALSE)))
     Output
-      <error/tidyselect:::error_disallowed_empty>
+      <error/tidyselect_error_empty_selection>
       Error in `relocate_loc()`:
-      ! Must select at least one item.
+      ! `before` and `after` must select at least one column.
     Code
       (expect_error(relocate_loc(mtcars, integer(), allow_empty = FALSE)))
     Output
-      <error/tidyselect:::error_disallowed_empty>
+      <error/tidyselect_error_empty_selection>
       Error in `relocate_loc()`:
-      ! Must select at least one item.
+      ! `before` and `after` must select at least one column.
     Code
       (expect_error(relocate_loc(mtcars, starts_with("z"), allow_empty = FALSE)))
     Output
-      <error/tidyselect:::error_disallowed_empty>
+      <error/tidyselect_error_empty_selection>
       Error in `relocate_loc()`:
-      ! Must select at least one item.
+      ! `before` and `after` must select at least one column.
+
+---
+
+    Code
+      (expect_error(relocate_loc(mtcars, before = integer(), allow_empty = FALSE)))
+    Output
+      <error/tidyselect_error_empty_selection>
+      Error in `relocate_loc()`:
+      ! `before` and `after` must select at least one column.
+    Code
+      (expect_error(relocate_loc(mtcars, starts_with("z"), allow_empty = FALSE)))
+    Output
+      <error/tidyselect_error_empty_selection>
+      Error in `relocate_loc()`:
+      ! `before` and `after` must select at least one column.
 
 # `before` and `after` forbid renaming
 

tests/testthat/test-eval-relocate.R

@@ -183,6 +183,16 @@ test_that("can forbid empty selections", {
   })
 })
 
+test_that("can forbid empty selections", {
+  x <- c(a = 1, b = 2, c = 3)
+
+  expect_snapshot({
+    (expect_error(relocate_loc(mtcars, before = integer(), allow_empty = FALSE)))
+    (expect_error(relocate_loc(mtcars, starts_with("z"), allow_empty = FALSE)))
+  })
+})
+
+
 test_that("`before` and `after` forbid renaming", {
   x <- c(a = 1, b = 2, c = 3)