diff --git a/src/expr/core/src/window_function/call.rs b/src/expr/core/src/window_function/call.rs
index 844513bb1888a..d672872c82037 100644
--- a/src/expr/core/src/window_function/call.rs
+++ b/src/expr/core/src/window_function/call.rs
@@ -154,11 +154,7 @@ pub struct RowsFrameBounds {
     pub end: FrameBound<usize>,
 }
 
-impl FrameBoundsImpl for RowsFrameBounds {
-    fn validate(&self) -> Result<()> {
-        FrameBound::validate_bounds(&self.start, &self.end)
-    }
-
+impl RowsFrameBounds {
     /// Check if the `ROWS` frame is canonical.
     ///
     /// A canonical `ROWS` frame is defined as:
@@ -174,6 +170,12 @@ impl FrameBoundsImpl for RowsFrameBounds {
     }
 }
 
+impl FrameBoundsImpl for RowsFrameBounds {
+    fn validate(&self) -> Result<()> {
+        FrameBound::validate_bounds(&self.start, &self.end)
+    }
+}
+
 #[derive(Display, Debug, Clone, Eq, PartialEq, Hash, EnumAsInner)]
 #[display(style = "TITLE CASE")]
 pub enum FrameBound<T> {