Question

I am newbie to Rails and trying to write application with TDD and BDD.

Now in one of the models there is a validation on length of a field. There is an RSpec having an example which checks length validation of this specific field.

Here is Model class

class Section < ActiveRecord::Base

    # Validations
    validates_presence_of :name, length: { maximum: 50 }

end

and RSpec

require 'spec_helper'

describe Section do
    before do
      @section = Section.new(name:'Test')
    end

    subject { @section }

    # Check for attribute accessor methods
    it { should respond_to(:name) }


    # Sanity check, verifying that the @section object is initially valid
    it { should be_valid }

    describe "when name is not present" do
        before { @section.name = "" }
        it { should_not be_valid }
    end

    describe "when name is too long" do
      before { @section.name = "a" * 52 }
      it { should_not be_valid }
    end
end

When I rung this spec example fails with following error

....F......

Failures:

  1) Section when name is too long 
     Failure/Error: it { should_not be_valid }
       expected valid? to return false, got true
     # ./spec/models/section_spec.rb:24:in `block (3 levels) in <top (required)>'

Finished in 0.17311 seconds
11 examples, 1 failure

Am I missing something here?

Also please suggest me some references to learn how Models should be tested especially relationship using RSpec (and Shoulda).

Answer 1

The validates_presence_of method does not have length option.
You should validate length with validates_length_of method:

class Section < ActiveRecord::Base
  # Validations
  validates_presence_of :name
  validates_length_of :name, maximum: 50
end

Or use rails3 new validation syntax:

class Section < ActiveRecord::Base
  # Validations
  validates :name, presence: true, length: {maximum: 50}
end