Module: MasonTestHelper

Defined in:
lib/mason_test_helper.rb

Overview

Mix this module into Test::Unit::TestCase to have access to these test helpers when using Test::Unit.

Here’s an example of how you can use these helper methods:

def test_basic_document
  before_html = %Q{
    <!DOCTYPE html
    PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" 
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
    <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
      <head>
        <title>Testing Rack::SexChange</title>
      </head>
      <body>
        Hi, Mom!
      </body>
    </html>
  }
  expected_html = %Q{
    <!DOCTYPE html
    PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" 
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
    <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
      <head>
        <title>Testing Rack::SexChange</title>
      </head>
      <body>
        Hi, Dad!
      </body>
    </html>
  }
  after_html = process_html(before_html, Rack::SexChange)
  assert_html_equal expected_html, after_html
end

And here’s an example of how you’d mix these helper methods into Test::Unit::TestCase:

require 'test/unit'
require 'rubygems'
require 'plastic_test_helper'

module Test
  module Unit
    class TestCase

      include MasonTestHelper

    end
  end
end

Instance Method Summary collapse

Instance Method Details

#assert_html_equal(expected_html_string, actual_html_string) ⇒ Object

this convenience method makes it easy to test changes to HTML strings



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# File 'lib/mason_test_helper.rb', line 81

def assert_html_equal(expected_html_string, actual_html_string)
  # Nokogiri does not preserve the same whitespace between tags when
  # it processes HTML.  This means we can't do a simple string comparison.
  # However, if we run both the expected HTML string and the actual HTML
  # string through Nokogiri, then the whitespace will be changed in
  # the same way and we can do a simple string comparison.
  expected = Nokogiri::HTML(expected_html_string).to_html
  actual = Nokogiri::HTML(actual_html_string).to_html
  preamble = "\n"
  preamble =  "*****************************************************\n"
  preamble << "* The actual HTML does not match the expected HTML. *\n"
  preamble << "* The differences are highlighted below.            *\n"
  preamble << "*****************************************************\n"
  message = preamble.magenta
  message << Diffy::Diff.new(expected, actual).to_s(:color)
  assert_block(message) { expected == actual }
end

#process_html(html, middleware_class, options = {}) ⇒ Object

This takes care of the “plumbing” involved in testing your middleware. All you have to provide is an input HTML string, the class of your middleware (not the name of your class or an object, but the class itself), and finally some optional options to use when instantiating your middleware class.

This method will run the input HTML string through the middleware and return the resulting HTML string (the body of the middleware’s response).

Examples:

resulting_html = process_html(input_html, Rack::Linkify)
resulting_html = process_html(input_html, Rack::Linkify, :twitter => true)



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# File 'lib/mason_test_helper.rb', line 73

def process_html(html, middleware_class, options={})
  app = lambda { |env| [200, {'Content-Type' => 'text/html'}, [html]] }
  app2 = middleware_class.new(app, options)
  Rack::MockRequest.new(app2).get('/', :lint => true).body
end