You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: change_ident_test.go
    path of file: ./repos/expr/test/patch
    
    the code of the file until where you have to start completion: package patch_test

import (
	"testing"

	"github.com/stretchr/testify/require"

	"github.com/expr-lang/expr"
	"github.com/expr-lang/expr/ast"
	"github.com/expr-lang/expr/vm
    
func (changeIdent) Visit(node *ast.Node) {
	id, ok := (*node).(*ast.IdentifierNode)
	if !ok {
		return
	}
	if id.Value == "foo" {
		// A correct way to patch the node:
		//
		//	newNode := &ast.IdentifierNode{Value: "bar"}
		//	ast.Patch(node, newNode)
		//
		// But we can do it in a wrong way:
		id.Value = "bar"
	}
}