Rails 3 custom validation and shoulda

Question

Am swinging between Shoulda and Rspec these days. I have read and played around a fair bit with RSpec but not that much with Shoulda. I find Shoulda's one line assertions easier to read and the test looks cleaner. But when I can't figure out how write a particular assertion in Shoulda I switch to RSpec. Not very happy about it though.

So here is what I did today. I wrote some custom validations for my model Course. A course has a start_date and an end_date. There are a few rules around it.

• start_date and end_date are both mandatory
• start_date cannot be later than today
• end_date cannot be before the start_date

I know there are quiet a few gems out there that could have done it for me. But coz I am new I thought it might be good idea to do it myself and learn as I go.

So this is what my model looks like

class Course < ActiveRecord::Base
  belongs_to :category
  has_many :batches, :dependent => :destroy
  accepts_nested_attributes_for :batches, :reject_if => lambda {|a| a[:code].blank?}, :allow_destroy => true
  has_and_belongs_to_many :students, :uniq => true

  validates_presence_of :name, :course_code, :total_seats
  validates_uniqueness_of :category_id, :scope => [:name, :course_code]

  validates :start_date, :presence => true, :course_start_date=>true
  validates :end_date, :presence => true, :course_end_date=>true
end

My custom validations are as follows

class CourseEndDateValidator < ActiveModel::EachValidator  
  def validate_each(object, attribute, value)
    if object.errors[attribute].blank? && object.errors[:start_date].blank?
      if value < object.start_date
        object.errors[attribute] << "cannot be later than start date"
      end
    end
  end
end

class CourseStartDateValidator < ActiveModel::EachValidator  
  def validate_each(object, attribute, value)
    if object.errors[attribute].blank?
      if value < DateTime.now.to_date
        object.errors[attribute] << "cannot be later than today"
      end
    end
  end
end

And following is my course_spec

require 'spec_helper'require 'date'

describe Course do

  context  'validations' do
    it { should validate_presence_of(:name)}
    it { should validate_presence_of(:course_code)}
    it { should validate_presence_of(:start_date)}
    it { should validate_presence_of(:end_date)}
    it { should validate_presence_of(:total_seats)}

    date = DateTime.now.to_date
    it { should allow_value(date).for(:start_date) }
    it { should_not allow_value(date - 10 ).for(:start_date) }
    it {should allow_value(date + 10).for(:end_date)}
  end

  context  'associations' do
    it { should belong_to(:category)}
    it { should have_many(:batches).dependent(:destroy)}
    it { should have_and_belong_to_many(:students) }
  end

  it " end date should not be before course start date" do
    course = FactoryGirl.build(:course, :end_date=>'2011-12-10')
    course.should be_invalid
  end
end

Now before I wrote the last "it" block using Rspec I had something like this in my validations context

context  'validations' do
    it { should validate_presence_of(:name)}
    it { should validate_presence_of(:course_code)}
    it { should validate_presence_of(:start_date)}
    it { should validate_presence_of(:end_date)}
    it { should validate_presence_of(:total_seats)}

    date = DateTime.now.to_date
    it { should allow_value(date).for(:start_date) }
    it { should_not allow_value(date - 10 ).for(:start_date) }
    it { should allow_value(date + 10).for(:end_date)}
    it { should_not allow_value(date - 10).for(:end_date)} # <-------------------
  end

And I got the following failure

Failures:

  1) Course validations
     Failure/Error: it { should_not allow_value(date - 10).for(:end_date)}
       Expected errors when end_date is set to Fri, 9 Dec 2011, got errors: ["name can't be blank (nil)", "course_code can't be blank (nil)", "total_seats can't be blank (nil)", "start_date can't be blank (nil)"]

Am not sure what am I doing wrong here. Is it my custom validation code that is not correct or I need to setup something before I run the last assertion so that start_date is not nil when testing end_date?

The validations work fine in the view. I mean I get the right validation errors depending on the kind of data I input. But am test is failing. I have been looking at this for a while now but cannot figure out what exactly am I doing wrong.

Answer 1

I think you could tackle this in one of two two ways:

Either you need to place you date = DateTime.now.to_date into to before(:each) block.

context  'validations' do
  before(:each) { date = DateTime.now.to_date }

  it { should allow_value(date).for(:start_date) }
  it { should_not allow_value(date - 10 ).for(:start_date) }
  it { should allow_value(date + 10).for(:end_date)}
  it { should_not allow_value(date - 10).for(:end_date)}
end

Or you could use the rails date helpers.

context  'validations' do
  it { should allow_value(Date.today).for(:start_date) }
  it { should_not allow_value(10.days.ago).for(:start_date) }
  it { should allow_value(10.days.from_now).for(:end_date)}
  it { should_not allow_value(10.days.ago).for(:end_date)}
end

Answer 2

@nickgrim already answered the question, but I want to add a comment. The point of describe and it is to encourage sentences that start with the words "describe" and "it". In your example, you've got this:

it " end date should not be before course start date" do
  # ...

"it end date ...." is not a sentence. Please write that as something like:

it "validates that end date should be >= start date" do