{"ast_node_type":"variable","tokens":[{"end":70,"kind":"keyword","start":0,"text":"if"}]}
        if let hir::ExprKind::Index(ref base, ref index, _) = e.kind {
    fn fix_index_builtin_expr(&mut self, e: &hir::Expr<'_>) {
            // All valid indexing looks like this; might encounter non-valid indexes at this point.