diff --git a/rust/lance-datagen/src/generator.rs b/rust/lance-datagen/src/generator.rs
index 26b79c0b08d..e3f53cf842d 100644
--- a/rust/lance-datagen/src/generator.rs
+++ b/rust/lance-datagen/src/generator.rs
@@ -3032,6 +3032,12 @@ mod tests {
             *genn.generate(RowCount::from(3), &mut rng).unwrap(),
             arrow_array::StringArray::from_iter_values(["user_0", "user_1", "user_2"])
         );
+
+        let mut genn = array::utf8_prefix_plus_counter("user_", true);
+        assert_eq!(
+            *genn.generate(RowCount::from(3), &mut rng).unwrap(),
+            arrow_array::LargeStringArray::from_iter_values(["user_0", "user_1", "user_2"])
+        );
     }
 
     #[test]