fix style

native/core/src/execution/datafusion/planner.rs

@@ -1493,7 +1493,7 @@ impl PhysicalPlanner {
 
     fn convert_count_to_if(
         &self,
-        children: &Vec<Expr>,
+        children: &[Expr],
         schema: Arc<Schema>,
     ) -> Result<Arc<dyn PhysicalExpr>, ExecutionError> {
         assert!(!children.is_empty(), "Children should not be empty");
@@ -1533,12 +1533,12 @@ impl PhysicalPlanner {
         partition_by: &[Arc<dyn PhysicalExpr>],
         sort_exprs: &[PhysicalSortExpr],
     ) -> Result<Arc<dyn WindowExpr>, ExecutionError> {
-        let (mut window_func_name, mut window_args): (String, Vec<Arc<dyn PhysicalExpr>>) =
-            (String::new(), Vec::new());
+        let window_func_name: String;
+        let window_args: Vec<Arc<dyn PhysicalExpr>>;
         if let Some(func) = &spark_expr.built_in_window_function {
             match &func.expr_struct {
                 Some(ExprStruct::ScalarFunc(f)) => {
-                    window_func_name.clone_from(&f.func);
+                    window_func_name = f.func.clone();
                     window_args = f
                         .args
                         .iter()