gorm/preload_test.go

package gorm_test

import "testing"

func getPreloadUser(name string) *User {
	return getPreparedUser(name, "Preload")
}

func checkUserHasPreloadData(user User, t *testing.T) {
	u := getPreloadUser(user.Name)
	if user.BillingAddress.Address1 != u.BillingAddress.Address1 {
		t.Error("Failed to preload user's BillingAddress")
	}

	if user.ShippingAddress.Address1 != u.ShippingAddress.Address1 {
		t.Error("Failed to preload user's ShippingAddress")
	}

	if user.CreditCard.Number != u.CreditCard.Number {
		t.Error("Failed to preload user's CreditCard")
	}

	if user.Company.Name != u.Company.Name {
		t.Error("Failed to preload user's Company")
	}

	if len(user.Emails) != len(u.Emails) {
		t.Error("Failed to preload user's Emails")
	} else {
		var found int
		for _, e1 := range u.Emails {
			for _, e2 := range user.Emails {
				if e1.Email == e2.Email {
					found++
					break
				}
			}
		}
		if found != len(u.Emails) {
			t.Error("Failed to preload user's email details")
		}
	}
}

func TestPreload(t *testing.T) {
	user1 := getPreloadUser("user1")
	DB.Save(user1)

	preloadDB := DB.Where("role = ?", "Preload").Preload("BillingAddress").Preload("ShippingAddress").
		Preload("CreditCard").Preload("Emails").Preload("Company")
	var user User
	preloadDB.Find(&user)
	checkUserHasPreloadData(user, t)

	user2 := getPreloadUser("user2")
	DB.Save(user2)

	user3 := getPreloadUser("user3")
	DB.Save(user3)

	var users []User
	preloadDB.Find(&users)

	for _, user := range users {
		checkUserHasPreloadData(user, t)
	}

	var users2 []*User
	preloadDB.Find(&users2)

	for _, user := range users2 {
		checkUserHasPreloadData(*user, t)
	}

	var users3 []*User
	preloadDB.Preload("Emails", "email = ?", user3.Emails[0].Email).Find(&users3)

	for _, user := range users3 {
		if user.Name == user3.Name {
			if len(user.Emails) != 1 {
				t.Errorf("should only preload one emails for user3 when with condition")
			}
		} else if len(user.Emails) != 0 {
			t.Errorf("should not preload any emails for other users when with condition")
		}
	}
}