From 474d9d643661bdc0eeb09c58d3629e7cfe3e7324 Mon Sep 17 00:00:00 2001
From: Richard Chien <stdrc@outlook.com>
Date: Wed, 10 Jan 2024 13:26:25 +0800
Subject: [PATCH] add ut for `range_except`

Signed-off-by: Richard Chien <stdrc@outlook.com>
---
 .../src/window_function/state/range_utils.rs  | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/src/expr/core/src/window_function/state/range_utils.rs b/src/expr/core/src/window_function/state/range_utils.rs
index 256eb1ce1227a..d0dd07f223041 100644
--- a/src/expr/core/src/window_function/state/range_utils.rs
+++ b/src/expr/core/src/window_function/state/range_utils.rs
@@ -123,6 +123,25 @@ mod tests {
 
     use super::*;
 
+    #[test]
+    fn test_range_except() {
+        fn test(a: Range<usize>, b: Range<usize>, expected: impl IntoIterator<Item = usize>) {
+            let (l, r) = range_except(a, b);
+            let set = l.into_iter().chain(r).collect::<HashSet<_>>();
+            assert_eq!(set, expected.into_iter().collect())
+        }
+
+        test(0..0, 0..0, []);
+        test(0..1, 0..1, []);
+        test(0..1, 0..2, []);
+        test(1..2, 0..2, []);
+        test(0..2, 0..1, [1]);
+        test(0..2, 1..2, [0]);
+        test(0..5, 2..3, [0, 1, 3, 4]);
+        test(2..5, 1..3, [3, 4]);
+        test(2..5, 4..5, [2, 3]);
+    }
+
     #[test]
     fn test_range_diff() {
         fn test(