build helper and test

DESCRIPTION

@@ -52,7 +52,8 @@ Imports:
     tibble,
     lifecycle,
     jsonlite,
-    jose
+    jose,
+    cli
 Suggests:
     clipr (>= 0.3.0),
     conflicted,

R/boxr__internal_misc.R

@@ -28,6 +28,33 @@ box_id <- function(x) {
     return(as.character(bit64::as.integer64(x)))
 }
 
+# ref: https://rlang.r-lib.org/reference/topic-error-call.html
+as_box_id <- function(x, arg = rlang::caller_arg(x), 
+                      call = rlang::caller_env()) {
+
+  # a box_id is a string that contains only digits
+
+  # do we need this?
+  if (is.null(x)) {
+    return(NULL)    
+  }
+
+  id  <- as.character(x)
+
+  has_only_digits <- stringr::str_detect(id, "^\\d+$")
+
+  if (!all(has_only_digits)) {
+    cli::cli_abort(
+      message = "{.arg {arg}} must contain only digits",
+      class = "boxr_id",
+      call = call
+    )
+  }
+
+  id
+}
+
+
 # helper to identify void values
 is_void <- function(x) {
   is.null(x) ||

tests/testthat/test_00_internal.R

@@ -38,4 +38,16 @@ test_that("stack_rows works", {
   expect_identical(stack_rows_tbl(list(list_a, list_b)), tibble_ab)
   expect_identical(stack_rows_df(list(list_a, list_b)), df_ab)
 
+})
+
+
+test_that("as_box_id works", {
+
+  expect_identical(as_box_id(c(1, 2, 3)), c("1", "2", "3"))
+  expect_identical(as_box_id(1407651371263), "1407651371263")
+
+  # TODO: update to expect_snapshot_error() when we use testthat 3e
+  expect_error(as_box_id("foo"), class = "boxr_id")
+  expect_error(as_box_id(3.4), class = "boxr_id")
+
 })