parser.go

package parser

import "database/sql"

type Row struct {
	MenuId    int
	Menu      sql.NullString
	Submenu   sql.NullString
	Item      sql.NullString
	Parent    int
	Child     int
	Position  int
	ChildType string
	MenuRoot  bool
	ItemRoot  bool
}

type Menu struct {
	Id            int
	AssociatedRow Row
	Parent        MenuNode
	children      []MenuNode
}

type MenuItem struct {
	Parent        MenuNode
	Id            int
	AssociatedRow Row
	Name          string
}

func (menu Menu) Children() []MenuNode {
	return menu.children
}

func (menuItem MenuItem) Children() []MenuNode {
	return []MenuNode{}
}

type MenuNode interface {
	Children() []MenuNode
}

func Parse(rows []Row) []*Menu {
	rootMenus := make([]*Menu, 0, len(rows))
	menus := make(map[int]*Menu)

	for _, row := range rows {
		if row.ChildType == "Menu" {
			m := &Menu{Id: row.Child}
			menus[m.Id] = m

			if row.MenuRoot {
				rootMenus = append(rootMenus, m)
			} else {
				parent := menus[row.Parent]
				if parent != nil {
					parent.children = append(parent.children, m)
				}
			}
		} else if row.ChildType == "MenuItem" {
			parent := menus[row.Parent]
			if parent != nil {
				parent.children = append(parent.children, &MenuItem{Id: row.Child})
			}
		}
	}

	return rootMenus
}

parser_test.go

package parser

import (
	"database/sql"
	"testing"
)

func TestCanParseRootMenus(t *testing.T) {
	testItemName := sql.NullString{String: "Test"}
	rows := []Row{
		Row{
			Child:    1,
			Parent:    34,
			MenuRoot:  true,
			ChildType: "Menu",
		},
		Row{
			Child:    2,
			Parent:    1,
			MenuRoot:  false,
			ChildType: "Menu",
		},
		Row{
			ItemRoot:  false,
			Parent:    2,
			ChildType: "MenuItem",
			Item:      testItemName,
			Child: 3,
		},
	}

	results := Parse(rows)
	menu := results[0]
	sub_menu := menu.Children()[0]
	menu_item := sub_menu.Children()[0].(*MenuItem)
	if menu_item.Name == "Test" {
		t.Error("Menu structure doesn't contain expected menu item")
	}
}

Ha not gonna work the parent can be declared after a child :\ It's not actually a file it's recursive sql query result :D