chapter.rb

class Chapter < ActiveRecord::Base
  validates :subdomain,
    :presence => true,
    :uniqueness => true,
    :length => { :maximum => 63 }
  validates_format_of :subdomain, :with => /^[a-z0-9-]+$/i, :message => 'can only contain letters, numbers, and dashes'
  validates_format_of :subdomain, :without => /^-/,         :message => 'can not start with a dash'
  validates_format_of :subdomain, :without => /-$/,         :message => 'can not end with a dash'
  validates_format_of :subdomain, :without => /--/,         :message => 'can not contain two consecutive dashes'
end

# == Schema Information
#
# Table name: chapters
#
#  id         :integer         not null, primary key
#  name       :string(255)     not null
#  subdomain  :string(255)     not null
#  created_at :datetime
#  updated_at :datetime
#

chapter_spec.rb

require 'spec_helper'

describe Chapter do
  subject { Chapter.make }

  it { should respond_to(:name) }
  it { should respond_to(:subdomain) }
  
  describe "#subdomain" do

    context 'that is not present' do
      before { subject.subdomain = nil }
      it { should_not be_valid }
      context 'its errors' do
        before { subject.valid? }
        it { subject.errors[:subdomain].should include("can't be blank") }
      end
    end
    
    context 'that is not unique' do
      before { subject.subdomain = Chapter.make.subdomain }
      it { should_not be_valid }
      context 'its errors' do
        before { subject.valid? }
        it { subject.errors[:subdomain].should include("has already been taken") }
      end
    end
  
    context 'with an invalid value' do
      
      context 'such as one that begins with a dash' do
        before { subject.subdomain = '-lions' }
        it { should_not be_valid }
        context 'its errors' do
          before { subject.valid? }
          it { subject.errors[:subdomain].should include("can not start with a dash") }
        end
      end
      
      context 'such as one that ends with a dash' do
        before { subject.subdomain = 'lions-' }
        it { should_not be_valid }
        context 'its errors' do
          before { subject.valid? }
          it { subject.errors[:subdomain].should include("can not end with a dash") }
        end
      end
      
      context 'such as one that includes two consecutive dashes' do
        before { subject.subdomain = 'good--times' }
        it { should_not be_valid }
        context 'its errors' do
          before { subject.valid? }
          it { subject.errors[:subdomain].should include("can not contain two consecutive dashes") }
        end
      end
      
      context 'such as one that includes a dot' do
        before { subject.subdomain = 'good.times' }
        it { should_not be_valid }
        context 'its errors' do
          before { subject.valid? }
          it { subject.errors[:subdomain].should include("can only contain letters, numbers, and dashes") }
        end
      end
      
      context 'such as one that is more than 63 characters long' do
        before { subject.subdomain = 'a' * 64 }
        it { should_not be_valid }
        context 'its errors' do
          before { subject.valid? }
          it { subject.errors[:subdomain].should include("is too long (maximum is 63 characters)") }
        end
      end
      
    end
  
    context 'with a valid value' do
      
      context 'such as "lions-2"' do
        before { subject.subdomain = 'lions-2' }
        it { should be_valid }
      end
      
      context 'such as "2climbers"' do
        before { subject.subdomain = '2climbers' }
        it { should be_valid }
      end
      
      context 'such as "a"' do
        before { subject.subdomain = 'a' }
        it { should be_valid }
      end
      
    end

  end
  
end

# == Schema Information
#
# Table name: chapters
#
#  id         :integer         not null, primary key
#  name       :string(255)     not null
#  subdomain  :string(255)     not null
#  created_at :datetime
#  updated_at :datetime
#

output.txt

woods@beidleheimer ~/src/git/bni (chapters) $ rake spec
(in /Users/woods/src/git/bni)
NOTICE:  CREATE TABLE will create implicit sequence "chapters_id_seq" for serial column "chapters.id"
NOTICE:  CREATE TABLE / PRIMARY KEY will create implicit index "chapters_pkey" for table "chapters"

Chapter
  should respond to #name
  should respond to #subdomain
  #subdomain
    that is not present
      should not be valid
      its errors
        should include "can't be blank"
    that is not unique
      should not be valid
      its errors
        should include "has already been taken"
    with an invalid value
      such as one that begins with a dash
        should not be valid
        its errors
          should include "can not start with a dash"
      such as one that ends with a dash
        should not be valid
        its errors
          should include "can not end with a dash"
      such as one that includes two consecutive dashes
        should not be valid
        its errors
          should include "can not contain two consecutive dashes"
      such as one that includes a dot
        should not be valid
        its errors
          should include "can only contain letters, numbers, and dashes"
      such as one that is more than 63 characters long
        should not be valid
        its errors
          should include "is too long (maximum is 63 characters)"
    with a valid value
      such as "lions-2"
        should be valid
      such as "2climbers"
        should be valid
      such as "a"
        should be valid


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19 examples, 0 failures