允许空白上应该validate_uniqueness_of

Question

使用早该，任何想法有这个测试时，如何让空：

should validate_uniqueness_of(:email) 

感谢。

Answer 1

should allow_value(" ").for(:email) 
should allow_value(nil).for(:email) 

Answer 2

也许

should validate_uniqueness_of(:email, :allow_blank => true) 

Answer 3

我已经想通了！ validate_uniqueness_of依赖于当前正在数据库第一条记录上测试的属性的值。因此，如果数据库中的第一条记录恰好为空，或者该属性为nul，则测试将始终发出如下错误：“Failure/Error：it {should validate_uniqueness_of（：customer_number）.case_insensitive.scoped_to（：user_id）}当customer_number被设置为零，没有错误时，预期的错误包括“已经被采用”。

那么我们如何解决这个问题呢？确保删除所有现有记录，并且第一条记录包含属性的填充值。

型号：

validates_uniqueness_of :customer_number, :scope => :user_id, :case_sensitive => false, :allow_blank => true, :allow_nil => true 

型号规格：

describe 'Validation' do 

    it { should allow_value('').for(:customer_number) } 

    describe 'When a user exists with the same customer_number and user' do 
    before(:each) do 
     Customer.destroy_all 
     # Saving a single customer to validate uniqueness. 
     @existing = Factory(:customer, :customer_number => 'test') # If you leave customer_number blank here the matcher will check if it can save a new record with a blank customer_number which is possible since we allow blanks. So make sure your first record has a filled in value!! 
    end 

    subject do 
     Factory.build(:customer) 
    end 

    it { should validate_uniqueness_of(:customer_number).case_insensitive.scoped_to(:user_id) } 
    end 
end 

希望这澄清了一些人的问题:)