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: idna_test.go
    path of file: ./repos/go-starter-kit/vendor/golang.org/x/text/internal/export/idna
    
    the code of the file until where you have to start completion: // Copyright 2016 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package idna

import (
	"fmt"
	"strconv"
	"strings"
	"testing"

	"golang.org/x/text/internal/gen"
	"golang.org/x/text/internal/testtext"
	"golang.org/x/text/internal/ucd"
)

func TestAllocToUnicode(t *testing.T) {
	avg := testtext.AllocsPerRun(1000, func() {
		ToUnicode("www.golang.org")
	})
	if avg > 0 {
		t.Errorf("go
    
func doTest(t *testing.T, f func(string) (string, error), name, input, want, errors string) {
	errors = strings.Trim(errors, "[]")
	test := "ok"
	if errors != "" {
		test = "err:" + errors
	}
	// Replace some of the escape sequences to make it easier to single out
	// tests on the command name.
	in := strings.Trim(strconv.QuoteToASCII(input), `"`)
	in = strings.Replace(in, `\u`, "#", -1)
	in = strings.Replace(in, `\U`, "#", -1)
	name = fmt.Sprintf("%s/%s/%s", name, in, test)

	testtext.Run(t, name, func(t *testing.T) {
		got, err := f(input)

		if err != nil {
			code := err.(interface {
				code() string
			}).code()
			if strings.Index(errors, code) == -1 {
				t.Errorf("error %q not in set of expected errors {%v}", code, errors)
			}
		} else if errors != "" {
			t.Errorf("no errors; want error in {%v}", errors)
		}

		if want != "" && got != want {
			t.Errorf(`string: got %+q; want %+q`, got, want)
		}
	})
}