t.Errorf("no error should happened when deleting company, but got %v", err)
	}

	if users[0].CompanyID != nil || users[0].Company.ID != 0 {
		t.Errorf("users[0]'s company should be deleted'")
	}

	AssertAssociationCount(t, users, "Company", 2, "After Delete")

	// Clear
	DB.Model(&users).Association("Company").Clear()
	AssertAssociationCount(t, users, "Company", 0, "After Clear")