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: buildinfo_test.go
    path of file: ./repos/gccrs/libgo/go/debug/buildinfo
    
    the code of the file until where you have to start completion: // Copyright 2021 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 buildinfo_test

import (
	"bytes"
	"debug/buildinfo"
	"flag"
	"internal/testenv"
	"os"
	"os/exec"
	"path"
	"path/filepath"
	"regexp"
	"runtime"
	"strings"
	"testing"
)

var flagAll = flag.Bool("all", false, "test all supported GOOS/GOARCH platforms, instead of only the current platform")

// TestReadFile confirms that ReadFile can read build information from binaries
// on supported target platforms. It builds a trivial binary on the current
// platforms (or all platforms if -all is set) in various configurations and
// checks that build information can or cannot be read.
func TestReadFile(t *testing.T) {
	if testing.Short() {
		t.Skip("test requires compiling and linking, which may be slow")
	}
	testenv.MustHaveGoBuild(t)

	type platform struct{ goos, goarch string }
	platforms := []platform{
		{"aix", "ppc64"},
		{"darwin", "amd64"},
		{"darwin", "arm64"},
		{"linux", "386"},
		{"linux", "amd64"},
		{"windows", "386"},
		{"windows", "amd64"},
	}
	runtimePlatform := platform{runtime.GOOS, runtime.GOARCH}
	haveRuntimePlatform := false
	for _, p := range platforms {
		if p == runtimePlatform {
			haveRuntimePlatform = true
			break
		}
	}
	if !haveRuntimePlatform {
		platforms = append(platforms, runtimePlatform)
	}

	buildWithModules := func(t *testing.T, goos, goarch string) string {
		dir := t.TempDir()
		gomodPath := filepath.Join(dir, "go.mod")
		gomodData := []byte("module example.com/m\ngo 1.18\n")
		if err := os.WriteFile(gomodPath, gomodData, 0666); err != nil {
			t.Fatal(err)
		}
		helloPath := filepath.Join(dir, "hello.go")
		helloData := []byte("package main\nfunc main() {}\n")
		if err := os.WriteFile(helloPath, helloData, 0666); err != nil {
			t.Fatal(err)
		}
		outPath := filepath.Join(dir, path.Base(t.Name()))
		cmd := exec.Command("go", "build", "-o="+outPath)
		cmd.Dir = dir
		cmd.Env = append(os.Environ(), "GO111MODULE=on", "GOOS="+goos, "GOARCH="+goarch)
		stderr := &bytes.Buffer{}
		cmd.Stderr = stderr
		if err := cmd.Run(); err != nil {
			t.Fatalf("failed building test file: %v\n%s", err, stderr.Bytes())
		}
		return outPath
	}

	buildWithGOPATH := func(t *testing.T, goos, goarch string) string {
		gopathDir := t.TempDir()
		pkgDir := filepath.Join(gopathDir, "src/example.com/m")
		if err := os.MkdirAll(pkgDir, 0777); err != nil {
			t.Fatal(err)
		}
		helloPath := filepath.Join(pkgDir, "hello.go")
		helloData := []byte("package main\nfunc main() {}\n")
		if err := os.WriteFile(helloPath, helloData, 0666); err != nil {
			t.Fatal(err)
		}
		outPath := filepath.Join(gopathDir, path.Base(t.Name()))
		cmd := exec.Command("go", "build", "-o="+outPath)
		cmd.Dir = pkgDir
		cmd.Env = append(os.Environ(), "GO111MODULE=off", "GOPATH="+gopathDir, "GOOS="+goos, "GOARCH="+goarch)
		stderr := &bytes.Buffer{}
		cmd.Stderr = stderr
		if err := cmd.Run(); err != nil {
			t.Fatalf("failed building test file: %v\n%s", err, stderr.Bytes())
		}
		return outPath
	}

	damageBuildInfo := func(t *testing.T, name string) {
		data, err := os.ReadFile(name)
		if err != nil {
			t.Fatal(err)
		}
		i := bytes.Index(data, []byte("\xff Go buildinf:"))
		if i < 0 {
			t.Fatal("Go buildinf not found")
		}
		data[i+2] = 'N'
		if err := os.WriteFile(name, data, 0666); err != nil {
			t.Fatal(err)
		}
	}

	goVersionRe := regexp.MustCompile("(?m)^go\t.*\n")
	buildRe := regexp.MustCompile("(?m)^build\t.*\n")
	cleanOutputForComparison := func(got string) string {
		// Remove or replace anything that might depend on the test's environment
		// so we can check the output afterward with a string comparison.
		// We'll remove all build lines except the compiler, just to make sure
		// build lines are included.
		got = goVersionRe.ReplaceAllString(got, "go\tGOVERSION\n")
		got = buildRe.ReplaceAllStringFunc(got, func(match string) string {
			if strings.HasPrefix(match, "build\t-compiler=") {
				return match
			}
			return ""
		})
		return got
	}

	cases := []struct {
		name    string
		build   func(t *testing.T, goos, goarch string) string
		want    string
		wantErr string
	}{
		{
			name: "doesnotexist",
			build: func(t *testing.T, goos, goarch string) string {
				return "doesnotexist.txt"
			},
			wantErr: "doesnotexist",
		},
		{
			name: "empty",
			build: func(t *testing.T, _, _ string) string {
				dir := t.TempDir()
				name := filepath.Join(dir, "empty")
				if err := os.WriteFile(name, nil, 0666); err != nil {
					t.Fatal(err)
				}
				return name
			},
			wantErr: "unrecognized file format",
		},
		{
			name:  "valid_modules",
			build: buildWit
    
func TestReadFile(t *testing.T) {
	if testing.Short() {
		t.Skip("test requires compiling and linking, which may be slow")
	}
	testenv.MustHaveGoBuild(t)

	type platform struct{ goos, goarch string }
	platforms := []platform{
		{"aix", "ppc64"},
		{"darwin", "amd64"},
		{"darwin", "arm64"},
		{"linux", "386"},
		{"linux", "amd64"},
		{"windows", "386"},
		{"windows", "amd64"},
	}
	runtimePlatform := platform{runtime.GOOS, runtime.GOARCH}
	haveRuntimePlatform := false
	for _, p := range platforms {
		if p == runtimePlatform {
			haveRuntimePlatform = true
			break
		}
	}
	if !haveRuntimePlatform {
		platforms = append(platforms, runtimePlatform)
	}

	buildWithModules := func(t *testing.T, goos, goarch string) string {
		dir := t.TempDir()
		gomodPath := filepath.Join(dir, "go.mod")
		gomodData := []byte("module example.com/m\ngo 1.18\n")
		if err := os.WriteFile(gomodPath, gomodData, 0666); err != nil {
			t.Fatal(err)
		}
		helloPath := filepath.Join(dir, "hello.go")
		helloData := []byte("package main\nfunc main() {}\n")
		if err := os.WriteFile(helloPath, helloData, 0666); err != nil {
			t.Fatal(err)
		}
		outPath := filepath.Join(dir, path.Base(t.Name()))
		cmd := exec.Command("go", "build", "-o="+outPath)
		cmd.Dir = dir
		cmd.Env = append(os.Environ(), "GO111MODULE=on", "GOOS="+goos, "GOARCH="+goarch)
		stderr := &bytes.Buffer{}
		cmd.Stderr = stderr
		if err := cmd.Run(); err != nil {
			t.Fatalf("failed building test file: %v\n%s", err, stderr.Bytes())
		}
		return outPath
	}

	buildWithGOPATH := func(t *testing.T, goos, goarch string) string {
		gopathDir := t.TempDir()
		pkgDir := filepath.Join(gopathDir, "src/example.com/m")
		if err := os.MkdirAll(pkgDir, 0777); err != nil {
			t.Fatal(err)
		}
		helloPath := filepath.Join(pkgDir, "hello.go")
		helloData := []byte("package main\nfunc main() {}\n")
		if err := os.WriteFile(helloPath, helloData, 0666); err != nil {
			t.Fatal(err)
		}
		outPath := filepath.Join(gopathDir, path.Base(t.Name()))
		cmd := exec.Command("go", "build", "-o="+outPath)
		cmd.Dir = pkgDir
		cmd.Env = append(os.Environ(), "GO111MODULE=off", "GOPATH="+gopathDir, "GOOS="+goos, "GOARCH="+goarch)
		stderr := &bytes.Buffer{}
		cmd.Stderr = stderr
		if err := cmd.Run(); err != nil {
			t.Fatalf("failed building test file: %v\n%s", err, stderr.Bytes())
		}
		return outPath
	}

	damageBuildInfo := func(t *testing.T, name string) {
		data, err := os.ReadFile(name)
		if err != nil {
			t.Fatal(err)
		}
		i := bytes.Index(data, []byte("\xff Go buildinf:"))
		if i < 0 {
			t.Fatal("Go buildinf not found")
		}
		data[i+2] = 'N'
		if err := os.WriteFile(name, data, 0666); err != nil {
			t.Fatal(err)
		}
	}

	goVersionRe := regexp.MustCompile("(?m)^go\t.*\n")
	buildRe := regexp.MustCompile("(?m)^build\t.*\n")
	cleanOutputForComparison := func(got string) string {
		// Remove or replace anything that might depend on the test's environment
		// so we can check the output afterward with a string comparison.
		// We'll remove all build lines except the compiler, just to make sure
		// build lines are included.
		got = goVersionRe.ReplaceAllString(got, "go\tGOVERSION\n")
		got = buildRe.ReplaceAllStringFunc(got, func(match string) string {
			if strings.HasPrefix(match, "build\t-compiler=") {
				return match
			}
			return ""
		})
		return got
	}

	cases := []struct {
		name    string
		build   func(t *testing.T, goos, goarch string) string
		want    string
		wantErr string
	}{
		{
			name: "doesnotexist",
			build: func(t *testing.T, goos, goarch string) string {
				return "doesnotexist.txt"
			},
			wantErr: "doesnotexist",
		},
		{
			name: "empty",
			build: func(t *testing.T, _, _ string) string {
				dir := t.TempDir()
				name := filepath.Join(dir, "empty")
				if err := os.WriteFile(name, nil, 0666); err != nil {
					t.Fatal(err)
				}
				return name
			},
			wantErr: "unrecognized file format",
		},
		{
			name:  "valid_modules",
			build: buildWithModules,
			want: "go\tGOVERSION\n" +
				"path\texample.com/m\n" +
				"mod\texample.com/m\t(devel)\t\n" +
				"build\t-compiler=gc\n",
		},
		{
			name: "invalid_modules",
			build: func(t *testing.T, goos, goarch string) string {
				name := buildWithModules(t, goos, goarch)
				damageBuildInfo(t, name)
				return name
			},
			wantErr: "not a Go executable",
		},
		{
			name:  "valid_gopath",
			build: buildWithGOPATH,
			want: "go\tGOVERSION\n" +
				"path\texample.com/m\n" +
				"build\t-compiler=gc\n",
		},
		{
			name: "invalid_gopath",
			build: func(t *testing.T, goos, goarch string) string {
				name := buildWithGOPATH(t, goos, goarch)
				damageBuildInfo(t, name)
				return name
			},
			wantErr: "not a Go executable",
		},
	}

	for _, p := range platforms {
		p := p
		t.Run(p.goos+"_"+p.goarch, func(t *testing.T) {
			if p != runtimePlatform && !*flagAll {
				t.Skipf("skipping platforms other than %s_%s because -all was not set", runtimePlatform.goos, runtimePlatform.goarch)
			}
			for _, tc := range cases {
				tc := tc
				t.Run(tc.name, func(t *testing.T) {
					t.Parallel()
					name := tc.build(t, p.goos, p.goarch)
					if info, err := buildinfo.ReadFile(name); err != nil {
						if tc.wantErr == "" {
							t.Fatalf("unexpected error: %v", err)
						} else if errMsg := err.Error(); !strings.Contains(errMsg, tc.wantErr) {
							t.Fatalf("got error %q; want error containing %q", errMsg, tc.wantErr)
						}
					} else {
						if tc.wantErr != "" {
							t.Fatalf("unexpected success; want error containing %q", tc.wantErr)
						}
						got := info.String()
						if clean := cleanOutputForComparison(string(got)); got != tc.want && clean != tc.want {
							t.Fatalf("got:\n%s\nwant:\n%s", got, tc.want)
						}
					}
				})
			}
		})
	}
}