base.Fatalf("go: %s already exists", gowork)
	}

	goV := gover.Local() // Use current Go version by default
	wf := new(modfile.WorkFile)
	wf.Syntax = new(modfile.FileSyntax)
	wf.AddGoStmt(goV)
	workUse(ctx, gowork, wf, args)
	modload.WriteWorkFile(gowork, wf)

	w = 0
	for _, r := range f.Replace {
		if r.Old.Path != "" {
			f.Replace[w] = r
			w++
		}
	}
	f.Replace = f.Replace[:w]

	f.Syntax.Cleanup()
}

func (f *WorkFile) AddGoStmt(version string) error {
	if !GoVersionRE.MatchString(version) {
		return fmt.Errorf("invalid language version %q", version)
	}
	if f.Go == nil {
		stmt := &Line{Token: []string{"go", version}}
		f.Go = &Go{

}

func mustHaveCompleteRequirements() bool {
	return cfg.BuildMod != "mod" && !inWorkspaceMode()
}

// addGoStmt adds a go directive to the go.mod file if it does not already
// include one. The 'go' version added, if any, is the latest version supported
// by this toolchain.
func addGoStmt(modFile *modfile.File, mod module.Version, v string) {
	if modFile.Go != nil && modFile.Go.Version != "" {
		return
	}

	if err != nil {
		base.Fatalf("go: errors parsing %s:\n%s", base.ShortPath(gowork), err)
	}

	if *editGo == "none" {
		workFile.DropGoStmt()
	} else if *editGo != "" {
		if err := workFile.AddGoStmt(*editGo); err != nil {
			base.Fatalf("go: internal error: %v", err)
		}
	}
	if *editToolchain == "none" {
		workFile.DropToolchainStmt()
	} else if *editToolchain != "" {

	}

	if *editModule != "" {
		modFile.AddModuleStmt(*editModule)
	}

	if *editGo == "none" {
		modFile.DropGoStmt()
	} else if *editGo != "" {
		if err := modFile.AddGoStmt(*editGo); err != nil {
			base.Fatalf("go: internal error: %v", err)
		}
	}
	if *editToolchain == "none" {
		modFile.DropToolchainStmt()
	} else if *editToolchain != "" {

	w = 0
	for _, r := range f.Retract {
		if r.Low != "" || r.High != "" {
			f.Retract[w] = r
			w++
		}
	}
	f.Retract = f.Retract[:w]

	f.Syntax.Cleanup()
}

func (f *File) AddGoStmt(version string) error {
	if !GoVersionRE.MatchString(version) {
		return fmt.Errorf("invalid language version %q", version)
	}
	if f.Go == nil {
		var hint Expr