add test for bind error size

Signed-off-by: Runji Wang <[email protected]>

src/binder/error.rs

@@ -195,6 +195,15 @@ mod tests {
 
     use super::*;
 
+    #[test]
+    fn test_bind_error_size() {
+        assert_eq!(
+            std::mem::size_of::<BindError>(),
+            std::mem::size_of::<usize>(),
+            "the size of BindError should be one pointer"
+        );
+    }
+
     #[test]
     fn test_highlight_sql() {
         let sql = "SELECT * FROM table WHERE id = 1";