[Rails] RSpecのリファクタリング ref: http://qiita.com/kidachi_/items/ec184deb106e4e5c90c3

application_helper.rb

module ApplicationHelper
  # ページごとの完全なタイトルを返却
  def full_title(page_title)
    base_title = "Ruby on Rails Tutorial Sample App"
    if page_title.empty?
      base_title
    else
      "#{base_title} | #{page_title}"
    end
  end
end

application_helper_spec.rb

require 'spec_helper'

describe ApplicationHelper do

  describe "full_title" do
    it "should include the page title" do
      expect(full_title("foo")).to match(/foo/)
    end

    it "should include the base title" do
      expect(full_title("foo")).to match(/^Ruby on Rails Tutorial Sample App/)
    end

    it "should not include a bar for the home page" do
      expect(full_title("")).not_to match(/\|/)
    end
  end
end

file1.txt

describe "Static pages" do
  describe "Home page" do
  end
end

file2.txt

it "should have the h1 'Sample App'" do
  visit root_path
  page.should have_selector('h1', text: 'Sample App')
end

file7.txt

let(:variable)    { 'hoge' }
# 値’hoge’を持つ変数variableが使えるようになる。

file8.txt

describe "Static pages" do
  subject { page }

  shared_examples_for "fuga" do
    it { should have_content(variable1) }
    it { should have_title(full_title(variable2)) }
  end
  ~

file9.txt

  describe "Home page" do
    let(:variable1)    { 'Sample App' }
    let(:variable2) { '' }
    it_should_behave_like "fuga"
  end

static_pages_spec.rb

require 'spec_helper'

describe "Static pages" do

  subject { page }

  shared_examples_for "all static pages" do
    it { should have_content(heading) }
    it { should have_title(full_title(page_title)) }
  end

  describe "Home page" do
    before { visit root_path }
    let(:heading)    { 'Sample App' }
    let(:page_title) { '' }

    it_should_behave_like "all static pages"
    it { should_not have_title('| Home') }
  end

  describe "About page" do
    before { visit about_path }
    let(:heading) { 'About' }
    let(:page_title) { 'About' }

    it_should_behave_like "all static pages"
  end