Question

I have a model with a relationship like this:

class Category < ActiveRecord::Base
 has_many :items
end

class Item < ActiveRecord::Base
  belongs_to :category
  before_save :default_values
  validates_presence_of :header

  def default_values
    if self.category.cat_is_enabled==true
      self.is_enabled=true
    end
  end
end

I’d like to just check the validates_presence_of with:

require ‘spec_helper’

describe Item do
  pending "add some examples to (or delete) #{__FILE__}"
  it "should have a header value" do
    mi=Item.create(:header => "").should_not be_valid
  end
end

but I get an error on this for “undefined method `cat_is_enabled’ for nil:NilClass”. How would I turn off default values? Is there a better way to test validations?

thx

Answer 1

Here’s an idea:

Code

class ActiveRecord::Base
  def self.without_callback(callback, &block)
    method = self.send(:instance_method, callback)
    self.send(:remove_method, callback)
    self.send(:define_method, callback) {true}
    yield
    self.send(:remove_method, callback)
    self.send(:define_method, callback, method)
  end
end 

Usage

Item.without_callback(:before_save) do
    mi = Item.create(:header => "").should_not be_valid
end

Credit: article from Intridea.