Validating boolean value in Rspec and Rails

Question

I'm pretty confused how to validate boolean values in Rspec and Rails. I understand everything except for false and nil are taken as true in Ruby. But when I use MySQL with Rails, it uses 1 for true and 0 for false (if my understanding is correct).

I have the following model spec. I'd like to test boolean value for superuser attribute.

• How can I write specs here?
• How can I write implementation code here?

• Are my specs and implementation code specific to a specific database (like MySQL and PostgreSQL)?

  require 'spec_helper'
  describe User do
    before(:each) do
      @valid_attributes = {
        :username => "mike",
        :password => "super_encryped_password",
        :email => "[email protected]",
        :superuser => true
      }  
    end
  
  
    it "should create a new instance given valid attributes" do
      User.create!(@valid_attributes)
    end
  
  
    it "should have true or false for superuser" do
      @valid_attributes[:superuser] = "hello"
      User.new(@valid_attributes).should have(1).error_on(:superuser)
    end
  end
  

Answer 1

I guess you want "should have true or false for superuser" to fail. But if you want it to fail, you should add a validation in the user:

validate :superuser_boolean

def superuser_boolean
  errors.add(:superuser, "Should be a boolean") if !superuser.is_a?(TrueClass) && !superuser.is_a?(FalseClass)
end

Answer 2

Basing off jordini's answer:

def superuser_boolean
  errors.add(:superuser, "Should be a boolean") if [true, false].include?(superuser)
end

No ugly is_a checks, just a simple include?.

Answer 3

Hi there.

def boolean?(val)
  !!val == val
end

Include it in your spec_helper or extend rspec with be_boolean.

Answer 4

One important thing is that ActiveRecord does typecasting behind the scenes, so you do not have to worry about how your database stores boolean values. You even need not validate that a field is boolean, as long as you set that field as boolean when preparing your migration. You may want to make sure the field is not nil though, with a validates_presence_of :superuser declaration in your model class.