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        <h1>Advanced Testing</h1><p>This guide will show you new ways of testing.
By referring to this guide, you will be able to:</p>
<ul>
<li>Understand test doubles</li>
<li>Write unit tests with rspec</li>
<li>Write integration tests with capybara</li>
<li>Manipulate time in your tests</li>
<li>Stub out calls to Web Services efficiently</li>
<li>Test the javascript frontend of your app</li>
</ul>

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              Chapters
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            <ol class="chapters">
<li><a href="#rspec">rspec</a>

<ul>
<li><a href="#a-simple-spec">A simple spec</a></li>
<li><a href="#example-model-spec">Example Model Spec</a></li>
<li><a href="#example-feature-spec">Example Feature Spec</a></li>
<li><a href="#kinds-of-tests">Kinds of Tests</a></li>
</ul></li>
<li><a href="#cucumber">Cucumber</a>

<ul>
<li><a href="#step-definitions">Step Definitions</a></li>
</ul></li>
<li><a href="#test-doubles">Test Doubles</a></li>
<li><a href="#testing-web-servcies">Testing Web Servcies</a></li>
<li><a href="#testing-time">Testing Time</a>

<ul>
<li><a href="#first-solution-write-your-own-matcher">First solution: write your own matcher:</a></li>
<li><a href="#second-solution-timecop">Second Solution: Timecop</a></li>
</ul></li>
<li><a href="#testing-javascript">Testing Javascript</a>

<ul>
<li><a href="#phantom-example">Phantom Example</a></li>
<li><a href="#phantom-in-rspec">Phantom in rspec</a></li>
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<li><a href="#example-app">Example App</a></li>
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<p class='slide_break_block'><a class='slide_break' id='slide-0' href='slides_advanced_testing.html#/0'>◻</a></p>
<h2 id="rspec"><a class="anchorlink" href="#rspec"><span>1</span> rspec</a></h2><p>Rspec is the second testing framework that is commonly used
with Ruby on Rails projects. According to <a href="https://www.ruby-toolbox.com/categories/testing_frameworks">ruby-toolbox.com</a>
it is used more often than the (built in) Minitest.</p><p>Rspec replaces minitest in all aspects of rails, including in scaffolds.</p><p>The first things you hav to know to get started:</p>
<ul>
<li>tests are found in <code>spec/*</code> (not <code>test/*</code>)</li>
<li>to run one test use <code>rspec &lt;filename&gt;</code> or <code>rspec &lt;filename&gt;:&lt;linenumber&gt;</code> on the command line</li>
<li>to run all tests use <code>rake spec</code></li>
</ul>
<p>(yes, sometimes you need the <code>r</code> in rspec, and other times you leave it out.)</p></div>
<div class='slide'>
<p class='slide_break_block'><a class='slide_break' id='slide-1' href='slides_advanced_testing.html#/1'>◻</a></p>
<h3 id="a-simple-spec"><a class="anchorlink" href="#a-simple-spec"><span>1.1</span> A simple spec</a></h3><p>A file can contain multiple test. You use <code>describe</code> and <code>it</code> to
structure the file. The arguments for <code>describe</code> and <code>it</code> are
used to describe the test in case of failure:</p><div class="interstitial code">
<pre><code class="highlight ruby"><span class="n">describe</span> <span class="no">Game</span> <span class="k">do</span>
  <span class="n">describe</span> <span class="s2">"#score"</span> <span class="k">do</span>
    <span class="n">it</span> <span class="s2">"returns 0 for all gutter games"</span> <span class="k">do</span>
      <span class="n">game</span> <span class="o">=</span> <span class="no">Game</span><span class="p">.</span><span class="nf">new</span>
      <span class="mi">20</span><span class="p">.</span><span class="nf">times</span> <span class="p">{</span> <span class="n">game</span><span class="p">.</span><span class="nf">roll</span><span class="p">(</span><span class="mi">0</span><span class="p">)</span> <span class="p">}</span>
      <span class="n">game</span><span class="p">.</span><span class="nf">score</span><span class="p">.</span><span class="nf">should</span> <span class="o">==</span> <span class="mi">0</span>
    <span class="k">end</span>
  <span class="k">end</span>
<span class="k">end</span>
</code></pre>
<button class="clipboard-button" data-clipboard-text="describe Game do
  describe &quot;#score&quot; do
    it &quot;returns 0 for all gutter games&quot; do
      game = Game.new
      20.times { game.roll(0) }
      game.score.should == 0
    end
  end
end
">Copy</button>
</div>
<p>The message when this test fails reads:</p><div class="interstitial code">
<pre><code class="highlight ruby"><span class="no">Failures</span><span class="p">:</span>

  <span class="mi">1</span><span class="p">)</span> <span class="no">Game</span><span class="c1">#score returns 0 for all gutter games</span>
     <span class="no">Failure</span><span class="o">/</span><span class="no">Error</span><span class="p">:</span> <span class="n">game</span><span class="p">.</span><span class="nf">score</span><span class="p">.</span><span class="nf">should</span> <span class="o">==</span> <span class="mi">0</span>
       <span class="ss">expected: </span><span class="mi">0</span>
            <span class="ss">got: </span><span class="mi">1</span> <span class="p">(</span><span class="n">using</span> <span class="o">==</span><span class="p">)</span>
     <span class="c1"># ./x_spec.rb:15:in `block (3 levels) in &lt;top (required)&gt;'</span>
</code></pre>
<button class="clipboard-button" data-clipboard-text="Failures:

  1) Game#score returns 0 for all gutter games
     Failure/Error: game.score.should == 0
       expected: 0
            got: 1 (using ==)
     # ./x_spec.rb:15:in `block (3 levels) in <top (required)>'
">Copy</button>
</div>
<p>It is a convention to actually use the Class under test as
the argument of <code>describe</code>.</p><p>Inside the test you can use ruby and rails. Instead of minitest's assertions
you formulate expectations with "should" (outdated) or "expect" (current):</p><div class="interstitial code">
<pre><code class="highlight ruby"><span class="n">game</span><span class="p">.</span><span class="nf">score</span><span class="p">.</span><span class="nf">should</span> <span class="o">==</span> <span class="mi">0</span>
<span class="n">expect</span><span class="p">(</span><span class="n">game</span><span class="p">.</span><span class="nf">score</span><span class="p">).</span><span class="nf">to</span> <span class="n">eq</span><span class="p">(</span><span class="mi">0</span><span class="p">)</span>
</code></pre>
<button class="clipboard-button" data-clipboard-text="game.score.should == 0
expect(game.score).to eq(0)
">Copy</button>
</div>
<p>There are two ways of writing matchers:</p><div class="interstitial code">
<pre><code class="highlight ruby"><span class="n">foo</span><span class="p">.</span><span class="nf">should</span> <span class="o">==</span> <span class="n">bar</span>
<span class="n">foo</span><span class="p">.</span><span class="nf">should</span> <span class="n">eq</span><span class="p">(</span><span class="n">bar</span><span class="p">)</span>       <span class="n">expect</span><span class="p">(</span><span class="n">foo</span><span class="p">).</span><span class="nf">to</span> <span class="n">eq</span><span class="p">(</span><span class="n">bar</span><span class="p">)</span>
<span class="n">foo</span><span class="p">.</span><span class="nf">should_not</span> <span class="n">eq</span><span class="p">(</span><span class="n">bar</span><span class="p">)</span>   <span class="n">expect</span><span class="p">(</span><span class="n">foo</span><span class="p">).</span><span class="nf">not_to</span> <span class="n">eq</span><span class="p">(</span><span class="n">bar</span><span class="p">)</span>
<span class="n">foo</span><span class="p">.</span><span class="nf">should</span> <span class="n">be</span> <span class="o">&lt;</span> <span class="mi">10</span>       <span class="n">expect</span><span class="p">(</span><span class="n">foo</span><span class="p">).</span><span class="nf">to</span> <span class="n">be</span> <span class="o">&lt;</span> <span class="mi">10</span>

<span class="s2">"a string"</span><span class="p">.</span><span class="nf">should_not</span> <span class="o">=~</span> <span class="sr">/a regex/</span>
<span class="n">expect</span><span class="p">(</span><span class="s2">"a string"</span><span class="p">).</span><span class="nf">not_to</span> <span class="n">match</span><span class="p">(</span><span class="sr">/a regex/</span><span class="p">)</span>

<span class="nb">lambda</span> <span class="p">{</span> <span class="n">do_something</span> <span class="p">}.</span><span class="nf">should</span> <span class="n">raise_error</span><span class="p">(</span><span class="no">SomeError</span><span class="p">)</span>
<span class="n">expect</span> <span class="p">{</span> <span class="n">something</span> <span class="p">}.</span><span class="nf">to</span> <span class="n">raise_error</span><span class="p">(</span><span class="no">SomeError</span><span class="p">)</span>
</code></pre>
<button class="clipboard-button" data-clipboard-text="foo.should == bar
foo.should eq(bar)       expect(foo).to eq(bar)
foo.should_not eq(bar)   expect(foo).not_to eq(bar)
foo.should be < 10       expect(foo).to be < 10

&quot;a string&quot;.should_not =~ /a regex/
expect(&quot;a string&quot;).not_to match(/a regex/)

lambda { do_something }.should raise_error(SomeError)
expect { something }.to raise_error(SomeError)
">Copy</button>
</div>
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<div class='slide'>
<p class='slide_break_block'><a class='slide_break' id='slide-2' href='slides_advanced_testing.html#/2'>◻</a></p>
<h3 id="example-model-spec"><a class="anchorlink" href="#example-model-spec"><span>1.2</span> Example Model Spec</a></h3><div class="interstitial code">
<pre><code class="highlight ruby"><span class="n">describe</span> <span class="no">Post</span> <span class="k">do</span>
  <span class="n">context</span> <span class="s2">"with 2 or more comments"</span> <span class="k">do</span>
    <span class="n">it</span> <span class="s2">"orders them in reverse chronologically"</span> <span class="k">do</span>
      <span class="n">post</span> <span class="o">=</span> <span class="no">Post</span><span class="p">.</span><span class="nf">create!</span>
      <span class="n">comment1</span> <span class="o">=</span> <span class="n">post</span><span class="p">.</span><span class="nf">comments</span><span class="p">.</span><span class="nf">create!</span><span class="p">(</span><span class="ss">:body</span> <span class="o">=&gt;</span> <span class="s2">"first comment"</span><span class="p">)</span>
      <span class="n">comment2</span> <span class="o">=</span> <span class="n">post</span><span class="p">.</span><span class="nf">comments</span><span class="p">.</span><span class="nf">create!</span><span class="p">(</span><span class="ss">:body</span> <span class="o">=&gt;</span> <span class="s2">"second comment"</span><span class="p">)</span>
      <span class="n">post</span><span class="p">.</span><span class="nf">reload</span><span class="p">.</span><span class="nf">comments</span><span class="p">.</span><span class="nf">should</span> <span class="o">==</span> <span class="p">[</span><span class="n">comment2</span><span class="p">,</span> <span class="n">comment1</span><span class="p">]</span>
    <span class="k">end</span>
  <span class="k">end</span>
<span class="k">end</span>
</code></pre>
<button class="clipboard-button" data-clipboard-text="describe Post do
  context &quot;with 2 or more comments&quot; do
    it &quot;orders them in reverse chronologically&quot; do
      post = Post.create!
      comment1 = post.comments.create!(:body => &quot;first comment&quot;)
      comment2 = post.comments.create!(:body => &quot;second comment&quot;)
      post.reload.comments.should == [comment2, comment1]
    end
  end
end
">Copy</button>
</div>
</div>
<div class='slide'>
<p class='slide_break_block'><a class='slide_break' id='slide-3' href='slides_advanced_testing.html#/3'>◻</a></p>
<h3 id="example-feature-spec"><a class="anchorlink" href="#example-feature-spec"><span>1.3</span> Example Feature Spec</a></h3><div class="interstitial code">
<pre><code class="highlight ruby"><span class="n">feature</span> <span class="s2">"Widget management"</span> <span class="k">do</span>
  <span class="n">scenario</span> <span class="s2">"User creates a new widget"</span> <span class="k">do</span>
    <span class="n">visit</span> <span class="s2">"/widgets/new"</span>
    <span class="n">fill_in</span> <span class="s2">"Name"</span><span class="p">,</span> <span class="ss">:with</span> <span class="o">=&gt;</span> <span class="s2">"My Widget"</span>
    <span class="n">click_button</span> <span class="s2">"Create Widget"</span>
    <span class="n">page</span><span class="p">.</span><span class="nf">should</span> <span class="n">have_text</span><span class="p">(</span><span class="s2">"Widget was created."</span><span class="p">)</span>
  <span class="k">end</span>
<span class="k">end</span>
</code></pre>
<button class="clipboard-button" data-clipboard-text="feature &quot;Widget management&quot; do
  scenario &quot;User creates a new widget&quot; do
    visit &quot;/widgets/new&quot;
    fill_in &quot;Name&quot;, :with => &quot;My Widget&quot;
    click_button &quot;Create Widget&quot;
    page.should have_text(&quot;Widget was created.&quot;)
  end
end
">Copy</button>
</div>
</div>
<div class='slide'>
<p class='slide_break_block'><a class='slide_break' id='slide-4' href='slides_advanced_testing.html#/4'>◻</a></p>
<h3 id="kinds-of-tests"><a class="anchorlink" href="#kinds-of-tests"><span>1.4</span> Kinds of Tests</a></h3>
<ul>
<li>Model specs</li>
<li>Controller specs</li>
<li>View specs</li>
<li>Helper specs</li>
<li>Mailer specs</li>
<li>Routing specs</li>
<li>Request specs</li>
<li>Feature specs</li>
</ul>
</div>
<div class='slide'>
<p class='slide_break_block'><a class='slide_break' id='slide-5' href='slides_advanced_testing.html#/5'>◻</a></p>
<h2 id="cucumber"><a class="anchorlink" href="#cucumber"><span>2</span> Cucumber</a></h2><p><img src="images/cucumber-1.png" alt=""></p><p><img src="images/cucumber-2.png" alt=""></p></div>
<div class='slide'>
<p class='slide_break_block'><a class='slide_break' id='slide-6' href='slides_advanced_testing.html#/6'>◻</a></p>
<h3 id="step-definitions"><a class="anchorlink" href="#step-definitions"><span>2.1</span> Step Definitions</a></h3><p>the magic behind cucumber:</p><div class="interstitial code">
<pre><code class="highlight ruby"><span class="no">Given</span> <span class="sr">/the following movies exist/</span> <span class="k">do</span> <span class="o">|</span><span class="n">movies_table</span><span class="o">|</span>
  <span class="n">movies_table</span><span class="p">.</span><span class="nf">hashes</span><span class="p">.</span><span class="nf">each</span> <span class="k">do</span> <span class="o">|</span><span class="n">movie</span><span class="o">|</span>
    <span class="no">Movie</span><span class="p">.</span><span class="nf">create</span><span class="p">(</span> <span class="n">movie</span> <span class="p">)</span>
  <span class="k">end</span>
<span class="k">end</span>
<span class="no">Then</span> <span class="sr">/^the director of "([^"]*)" should be "([^"]*)"$/</span> <span class="k">do</span> <span class="o">|</span><span class="n">title</span><span class="p">,</span> <span class="n">director</span><span class="o">|</span>
  <span class="n">m</span> <span class="o">=</span> <span class="no">Movie</span><span class="p">.</span><span class="nf">find_by_title</span><span class="p">(</span> <span class="n">title</span> <span class="p">)</span>
  <span class="n">m</span><span class="p">.</span><span class="nf">should_not</span> <span class="n">be_nil</span>
  <span class="n">m</span><span class="p">.</span><span class="nf">director</span><span class="p">.</span><span class="nf">should</span> <span class="o">==</span> <span class="n">director</span>
<span class="k">end</span>
</code></pre>
<button class="clipboard-button" data-clipboard-text="Given /the following movies exist/ do |movies_table|
  movies_table.hashes.each do |movie|
    Movie.create( movie )
  end
end
Then /^the director of &quot;([^&quot;]*)&quot; should be &quot;([^&quot;]*)&quot;$/ do |title, director|
  m = Movie.find_by_title( title )
  m.should_not be_nil
  m.director.should == director
end
">Copy</button>
</div>
</div>
<div class='slide'>
<p class='slide_break_block'><a class='slide_break' id='slide-7' href='slides_advanced_testing.html#/7'>◻</a></p>
<h2 id="test-doubles"><a class="anchorlink" href="#test-doubles"><span>3</span> Test Doubles</a></h2><p>According to Meszaros(2007)</p>
<ul>
<li><strong>Test stub</strong> provide canned answers to calls made during the test</li>
<li><strong>Mock object</strong> used for verifying "indirect output" of the tested code, by first defining the expectations before the tested code is executed</li>
<li><strong>Test spy</strong> used for verifying "indirect output" of the tested code, by asserting the expectations afterwards, without having defined the expectations before the tested code is executed</li>
<li><strong>Fake object</strong> used as a simpler implementation, e.g. using an in-memory database in the tests instead of doing real database access</li>
</ul>
</div>
<div class='slide'>
<p class='slide_break_block'><a class='slide_break' id='slide-8' href='slides_advanced_testing.html#/8'>◻</a></p>
<h2 id="testing-web-servcies"><a class="anchorlink" href="#testing-web-servcies"><span>4</span> Testing Web Servcies</a></h2><p>VCR</p></div>
<div class='slide'>
<p class='slide_break_block'><a class='slide_break' id='slide-9' href='slides_advanced_testing.html#/9'>◻</a></p>
<h2 id="testing-time"><a class="anchorlink" href="#testing-time"><span>5</span> Testing Time</a></h2><div class="interstitial code">
<pre><code class="highlight ruby"><span class="n">describe</span> <span class="s2">"sets done_at"</span> <span class="k">do</span>
  <span class="n">t</span> <span class="o">=</span> <span class="no">Todoitem</span><span class="p">.</span><span class="nf">create!</span><span class="p">(</span> <span class="ss">:text</span> <span class="o">=&gt;</span> <span class="s2">"write"</span> <span class="p">)</span>
  <span class="n">t</span><span class="p">.</span><span class="nf">done</span> <span class="o">=</span> <span class="kp">true</span>
  <span class="n">t</span><span class="p">.</span><span class="nf">save!</span>
  <span class="n">t</span><span class="p">.</span><span class="nf">reload</span>
  <span class="n">t</span><span class="p">.</span><span class="nf">done_at</span><span class="p">.</span><span class="nf">should</span> <span class="o">==</span> <span class="no">Time</span><span class="p">.</span><span class="nf">now</span>
<span class="k">end</span>
</code></pre>
<button class="clipboard-button" data-clipboard-text="describe &quot;sets done_at&quot; do
  t = Todoitem.create!( :text => &quot;write&quot; )
  t.done = true
  t.save!
  t.reload
  t.done_at.should == Time.now
end
">Copy</button>
</div>
<p><img src="images/timefail-1.png" alt="time fail"></p><p><img src="images/timefail-2.png" alt="time fail"></p></div>
<div class='slide'>
<p class='slide_break_block'><a class='slide_break' id='slide-10' href='slides_advanced_testing.html#/10'>◻</a></p>
<h3 id="first-solution-write-your-own-matcher"><a class="anchorlink" href="#first-solution-write-your-own-matcher"><span>5.1</span> First solution: write your own matcher:</a></h3><div class="interstitial code">
<pre><code class="highlight ruby"><span class="c1"># in your test:</span>
<span class="n">t</span><span class="p">.</span><span class="nf">done_at</span><span class="p">.</span><span class="nf">should</span> <span class="n">be_the_same_time_as</span><span class="p">(</span> <span class="no">Time</span><span class="p">.</span><span class="nf">zone</span><span class="p">.</span><span class="nf">now</span> <span class="p">)</span>

<span class="c1"># in spec_helper.rb:</span>
<span class="no">RSpec</span><span class="o">::</span><span class="no">Matchers</span><span class="p">.</span><span class="nf">define</span> <span class="ss">:be_the_same_time_as</span> <span class="k">do</span> <span class="o">|</span><span class="n">expected</span><span class="o">|</span>
  <span class="n">match</span> <span class="k">do</span> <span class="o">|</span><span class="n">actual</span><span class="o">|</span>
    <span class="n">expected</span><span class="p">.</span><span class="nf">to_i</span> <span class="o">==</span> <span class="n">actual</span><span class="p">.</span><span class="nf">to_i</span>
  <span class="k">end</span>
  <span class="n">failure_message_for_should</span> <span class="k">do</span> <span class="o">|</span><span class="n">actual</span><span class="o">|</span>
    <span class="s2">"expected that </span><span class="si">#{</span><span class="n">actual</span><span class="si">}</span><span class="s2"> (</span><span class="si">#{</span><span class="n">actual</span><span class="p">.</span><span class="nf">to_i</span><span class="si">}</span><span class="s2"> in seconds)&nbsp;would be a the same as </span><span class="si">#{</span><span class="n">expected</span><span class="si">}</span><span class="s2"> &nbsp;(</span><span class="si">#{</span><span class="n">expected</span><span class="p">.</span><span class="nf">to_i</span><span class="si">}</span><span class="s2"> in seconds)"</span>
  <span class="k">end</span>
<span class="k">end</span>
</code></pre>
<button class="clipboard-button" data-clipboard-text="# in your test:
t.done_at.should be_the_same_time_as( Time.zone.now )

# in spec_helper.rb:
RSpec::Matchers.define :be_the_same_time_as do |expected|
  match do |actual|
    expected.to_i == actual.to_i
  end
  failure_message_for_should do |actual|
    &quot;expected that #{actual} (#{actual.to_i} in seconds)&nbsp;would be a the same as #{expected} &nbsp;(#{expected.to_i} in seconds)&quot;
  end
end
">Copy</button>
</div>
<p><img src="images/timefail-3.png" alt=""></p></div>
<div class='slide'>
<p class='slide_break_block'><a class='slide_break' id='slide-11' href='slides_advanced_testing.html#/11'>◻</a></p>
<h3 id="second-solution-timecop"><a class="anchorlink" href="#second-solution-timecop"><span>5.2</span> Second Solution: Timecop</a></h3><div class="interstitial code">
<pre><code class="highlight ruby"><span class="n">it</span> <span class="s2">"sets done_at"</span> <span class="k">do</span>
    <span class="n">t</span> <span class="o">=</span> <span class="no">Todoitem</span><span class="p">.</span><span class="nf">create!</span><span class="p">(</span> <span class="ss">:text</span> <span class="o">=&gt;</span> <span class="s2">"write"</span> <span class="p">)</span>
       <span class="no">Timecop</span><span class="p">.</span><span class="nf">freeze</span> <span class="k">do</span>
       <span class="n">t</span><span class="p">.</span><span class="nf">done</span> <span class="o">=</span> <span class="kp">true</span>
       <span class="n">t</span><span class="p">.</span><span class="nf">save!</span>
       <span class="n">t</span><span class="p">.</span><span class="nf">reload</span>
       <span class="n">t</span><span class="p">.</span><span class="nf">done_at</span><span class="p">.</span><span class="nf">should</span> <span class="o">==</span> <span class="no">Time</span><span class="p">.</span><span class="nf">now</span>
    <span class="k">end</span>
<span class="k">end</span>
</code></pre>
<button class="clipboard-button" data-clipboard-text="it &quot;sets done_at&quot; do
    t = Todoitem.create!( :text => &quot;write&quot; )
       Timecop.freeze do
       t.done = true
       t.save!
       t.reload
       t.done_at.should == Time.now
    end
end
">Copy</button>
</div>
</div>
<div class='slide'>
<p class='slide_break_block'><a class='slide_break' id='slide-12' href='slides_advanced_testing.html#/12'>◻</a></p>
<h2 id="testing-javascript"><a class="anchorlink" href="#testing-javascript"><span>6</span> Testing Javascript</a></h2><p><img src="images/jasmine.png" alt=""></p><p><img src="images/phantomjs.png" alt=""></p></div>
<div class='slide'>
<p class='slide_break_block'><a class='slide_break' id='slide-13' href='slides_advanced_testing.html#/13'>◻</a></p>
<h3 id="phantom-example"><a class="anchorlink" href="#phantom-example"><span>6.1</span> Phantom Example</a></h3><div class="interstitial code">
<pre><code class="highlight javascript"><span class="kd">var</span> <span class="nx">page</span><span class="p">;</span>
<span class="nx">page</span> <span class="o">=</span> <span class="nf">require</span><span class="p">(</span><span class="dl">"</span><span class="s2">webpage</span><span class="dl">"</span><span class="p">).</span><span class="nf">create</span><span class="p">();</span>
<span class="nx">page</span><span class="p">.</span><span class="nf">open</span><span class="p">(</span><span class="dl">"</span><span class="s2">http://localhost:3000</span><span class="dl">"</span><span class="p">,</span> <span class="kd">function</span><span class="p">(</span><span class="nx">status</span><span class="p">)</span> <span class="p">{</span>
  <span class="kd">var</span> <span class="nx">string</span><span class="p">;</span>
  <span class="nx">string</span> <span class="o">=</span> <span class="nx">page</span><span class="p">.</span><span class="nf">evaluate</span><span class="p">(</span><span class="kd">function</span><span class="p">()</span> <span class="p">{</span>
    <span class="k">return</span> <span class="nf">$</span><span class="p">(</span><span class="dl">"</span><span class="s2">h1</span><span class="dl">"</span><span class="p">).</span><span class="nf">text</span><span class="p">();</span>
  <span class="p">});</span>
  <span class="nx">console</span><span class="p">.</span><span class="nf">log</span><span class="p">(</span><span class="dl">"</span><span class="s2">Title: </span><span class="dl">"</span> <span class="o">+</span> <span class="nx">string</span><span class="p">);</span>
  <span class="k">return</span> <span class="nx">phantom</span><span class="p">.</span><span class="nf">exit</span><span class="p">();</span>
<span class="p">});</span>
</code></pre>
<button class="clipboard-button" data-clipboard-text="var page;
page = require(&quot;webpage&quot;).create();
page.open(&quot;http://localhost:3000&quot;, function(status) {
  var string;
  string = page.evaluate(function() {
    return $(&quot;h1&quot;).text();
  });
  console.log(&quot;Title: &quot; + string);
  return phantom.exit();
});
">Copy</button>
</div>
<div class="interstitial code">
<pre><code class="highlight javascript"><span class="kd">var</span> <span class="nx">page</span><span class="p">;</span>
<span class="nx">page</span> <span class="o">=</span> <span class="nf">require</span><span class="p">(</span><span class="dl">"</span><span class="s2">webpage</span><span class="dl">"</span><span class="p">).</span><span class="nf">create</span><span class="p">();</span>
<span class="nx">page</span><span class="p">.</span><span class="nf">open</span><span class="p">(</span><span class="dl">"</span><span class="s2">http://localhost:3000</span><span class="dl">"</span><span class="p">,</span> <span class="kd">function</span><span class="p">(</span><span class="nx">status</span><span class="p">)</span> <span class="p">{</span>
  <span class="kd">var</span> <span class="nx">string</span><span class="p">;</span>
  <span class="nx">string</span> <span class="o">=</span> <span class="nx">page</span><span class="p">.</span><span class="nf">evaluate</span><span class="p">(</span><span class="kd">function</span><span class="p">()</span> <span class="p">{</span>
    <span class="k">return</span> <span class="nf">$</span><span class="p">(</span><span class="dl">"</span><span class="s2">h1</span><span class="dl">"</span><span class="p">).</span><span class="nf">text</span><span class="p">();</span>
  <span class="p">});</span>
  <span class="nx">console</span><span class="p">.</span><span class="nf">log</span><span class="p">(</span><span class="dl">"</span><span class="s2">Title: </span><span class="dl">"</span> <span class="o">+</span> <span class="nx">string</span><span class="p">);</span>
  <span class="k">return</span> <span class="nx">phantom</span><span class="p">.</span><span class="nf">exit</span><span class="p">();</span>
<span class="p">});</span>
</code></pre>
<button class="clipboard-button" data-clipboard-text="var page;
page = require(&quot;webpage&quot;).create();
page.open(&quot;http://localhost:3000&quot;, function(status) {
  var string;
  string = page.evaluate(function() {
    return $(&quot;h1&quot;).text();
  });
  console.log(&quot;Title: &quot; + string);
  return phantom.exit();
});
">Copy</button>
</div>
</div>
<div class='slide'>
<p class='slide_break_block'><a class='slide_break' id='slide-14' href='slides_advanced_testing.html#/14'>◻</a></p>
<h3 id="phantom-in-rspec"><a class="anchorlink" href="#phantom-in-rspec"><span>6.2</span> Phantom in rspec</a></h3><p>with capybara and poltergeist</p></div>
<div class='slide'>
<p class='slide_break_block'><a class='slide_break' id='slide-15' href='slides_advanced_testing.html#/15'>◻</a></p>
<h2 id="example-app"><a class="anchorlink" href="#example-app"><span>7</span> Example App</a></h2><p>Clone <a href="https://github.com/web-engineering/rails-example-test-the-todo">this app</a> and try out your new testing strategies!</p><p><img src="images/sample-app-todolist.png" alt="screenshot example app"></p></div>
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