Use withr::with_seed() in random_id()

DESCRIPTION

@@ -51,6 +51,7 @@ Imports:
     scales (>= 1.3.0),
     tidyselect (>= 1.2.1),
     vctrs,
+    withr,
     xml2 (>= 1.3.6)
 Suggests:
     digest (>= 0.6.31),
@@ -70,8 +71,7 @@ Suggests:
     shiny (>= 1.9.1),
     testthat (>= 3.1.9),
     tidyr,
-    webshot2 (>= 0.1.0),
-    withr
+    webshot2 (>= 0.1.0)
 Config/Needs/coverage: officer
 Config/Needs/website: quarto
 ByteCompile: true

NEWS.md

@@ -1,5 +1,7 @@
 # gt (development version)
 
+* The `random_id()` function now relies on `withr::with_seed()` and no longer affects the state of the random number generator in the global environment.
+
 # gt 0.11.1
 
 ## Breaking changes

R/helpers.R

@@ -2926,7 +2926,19 @@ cell_style_structure <- function(name, obj, subclass = name) {
 #' @export
 random_id <- function(n = 10) {
 
-  paste(sample(letters, n, replace = TRUE), collapse = "")
+  # use last 5 digits of system time as seed
+  random_id_seed <- Sys.time() |>
+    as.numeric() |>
+    as.character() |>
+    # remove decimal point
+    sub("\\.", "", x = _) |>
+    # select last 5 digits
+    sub("\\d*(\\d{5}$)", "\\1", x = _) |>
+    as.numeric()
+
+  withr::with_seed(random_id_seed, {
+    paste(sample(letters, n, replace = TRUE), collapse = "")
+  })
 }
 
 latex_special_chars <- c(

tests/testthat/test-helpers.R

@@ -0,0 +1,14 @@
+test_that("random_id() does not affect random seed", {
+
+  withr::with_seed(123, {
+    r1 <- runif(1)
+  })
+
+  withr::with_seed(123, {
+    id <- random_id()
+    r2 <- runif(1)
+  })
+
+  expect_equal(r1, r2)
+
+})