test all mardown engines if available

Gemfile

@@ -34,9 +34,12 @@ gem 'slim', :group => 'slim'
 gem 'RedCloth', :group => 'redcloth'
 gem 'coffee-script', '>= 2.0', :group => 'coffee-script'
 gem 'rdoc', :group => 'rdoc'
+gem 'kramdown', :group => 'kramdown'
+gem 'maruku', :group => 'maruku'
 
 platforms :ruby do
   gem 'rdiscount', :group => 'rdiscount'
+  gem 'bluecloth', :group => 'bluecloth'
 end
 
 platforms :ruby_18, :jruby do

test/markdown_test.rb

@@ -1,10 +1,6 @@
 require File.dirname(__FILE__) + '/helper'
 
-begin
-fail LoadError, "rdiscount not available" if defined? JRuby
-require 'rdiscount'
-
-class MarkdownTest < Test::Unit::TestCase
+MarkdownTest = proc do
   def markdown_app(&block)
     mock_app do
       set :views, File.dirname(__FILE__) + '/views'
@@ -13,16 +9,32 @@ class MarkdownTest < Test::Unit::TestCase
     get '/'
   end
 
+  def assert_like(a,b)
+    pattern = /\s*\n\s*| id=['"][^"']*["']/
+    assert_equal a.strip.gsub(pattern, ""), b.strip.gsub(pattern, "")
+  end
+
+  def setup
+    Tilt.prefer engine, 'markdown', 'mkd', 'md'
+    super
+  end
+
+  it 'uses the correct engine' do
+    assert_equal engine, Tilt[:md]
+    assert_equal engine, Tilt[:mkd]
+    assert_equal engine, Tilt[:markdown]
+  end
+
   it 'renders inline markdown strings' do
     markdown_app { markdown '# Hiya' }
     assert ok?
-    assert_equal "<h1>Hiya</h1>\n", body
+    assert_like "<h1>Hiya</h1>\n", body
   end
 
   it 'renders .markdown files in views path' do
     markdown_app { markdown :hello }
     assert ok?
-    assert_equal "<h1>Hello From Markdown</h1>\n", body
+    assert_like "<h1>Hello From Markdown</h1>", body
   end
 
   it "raises error if template not found" do
@@ -31,6 +43,14 @@ class MarkdownTest < Test::Unit::TestCase
   end
 end
 
-rescue LoadError
-  warn "#{$!.to_s}: skipping markdown tests"
+# Will generate RDiscountTest, KramdownTest, etc.
+Tilt.mappings['md'].each do |t|
+  begin
+    t.new { "" }
+    klass = Class.new(Test::Unit::TestCase) { define_method(:engine) { t }}
+    klass.class_eval(&MarkdownTest)
+    Object.const_set t.name[/[^:]+(?=Template$)/] << "Test", klass
+  rescue LoadError
+    warn "#{$!}: skipping markdown tests with #{t}"
+  end
 end