move check_fold_with_op function out

clippy_lints/src/methods/unnecessary_fold.rs

@@ -52,13 +52,6 @@ struct Replacement {
     has_generic_return: bool,
 }
 
-pub(super) fn check(
-    cx: &LateContext<'_>,
-    expr: &hir::Expr<'_>,
-    init: &hir::Expr<'_>,
-    acc: &hir::Expr<'_>,
-    fold_span: Span,
-) {
 fn check_fold_with_op(
     cx: &LateContext<'_>,
     expr: &hir::Expr<'_>,
@@ -121,6 +114,13 @@ fn check_fold_with_op(
     }
 }
 
+pub(super) fn check(
+    cx: &LateContext<'_>,
+    expr: &hir::Expr<'_>,
+    init: &hir::Expr<'_>,
+    acc: &hir::Expr<'_>,
+    fold_span: Span,
+) {
     // Check that this is a call to Iterator::fold rather than just some function called fold
     if !is_trait_method(cx, expr, sym::Iterator) {
         return;