How do I validate that two values do not equal each other in a Rails model?

Question

I have a User model, which has an email and a password field. For security, these may not be equal to each other. How can I define this in my model?

Answer 1

You can use a custom validation method to check this.

class User < ActiveRecord::Base
  # ...

  def validate
    if (self.email == self.password)
      errors.add(:password, "password cannot equal email")
      errors.add(:email, "email cannot equal password")
    end
  end
end