chore: Adds test to validate factor enum consistency

tests/testthat/test-datatype.R

@@ -224,12 +224,18 @@ test_that("contains_* functions for datatype work", {
 })
 
 test_that("Enum", {
-  expect_identical(
-    as_polars_series(c("z", "z", "k", "a"))$
-      cast(pl$Enum(c("z", "k", "a")))$
-      to_r(),
-    factor(c("z", "z", "k", "a"))
-  )
+  # Generate 100 random data frames with random
+  # orders for levels. They should always match
+  for (i in 1:100) {
+    expected_levels = sample(letters, length(letters))
+    expected_values = sample(letters, length(letters))
+    expect_identical(
+      as_polars_series(expected_values)$
+        cast(pl$Enum(expected_levels))$
+        to_r(),
+      factor(expected_values, levels = expected_levels)
+    )
+  }
 
   expect_grepl_error(pl$Enum(), "missing")
   expect_grepl_error(pl$Enum(1), "invalid series dtype")