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README.md

@@ -12,6 +12,7 @@ about using shoulda with Test::Unit.
 
 Matchers to test associations:
 
+```ruby
 describe Post do
   it { should belong_to(:user) }
   it { should have_many(:tags).through(:taggings) }
@@ -20,11 +21,13 @@ Matchers to test associations:
 describe User do
   it { should have_many(:posts) }
 end
+```
 
 ## ActiveModel Matchers
 
 Matchers to test validations and mass assignments:
 
+```ruby
 describe Post do
   it { should validate_uniqueness_of(:title) }
   it { should validate_uniqueness_of(:title).scoped_to(:user_id, :category_id) }
@@ -40,11 +43,13 @@ Matchers to test validations and mass assignments:
   it { should ensure_inclusion_of(:age).in_range(1..100) }
   it { should_not allow_mass_assignment_of(:password) }
 end
+```
 
 ## ActionController Matchers
 
 Matchers to test common patterns:
 
+```ruby
 describe PostsController, "#show" do
   context "for a fictional user" do
     before do
@@ -57,19 +62,23 @@ Matchers to test common patterns:
     it { should_not set_the_flash }
   end
 end
+```
 
 ## Independent Matchers
 
 Matchers to test non-Rails-dependent code:
 
+```ruby
 describe Human do
   it { should delegate_method(:work).to(:robot) }
 end
+```
 
 ## Installation
 
 In Rails 3 and Bundler, add the following to your Gemfile:
 
+```ruby
 group :test do
   gem "shoulda-matchers"
 end
@@ -79,6 +88,7 @@ In Rails 3 and Bundler, add the following to your Gemfile:
 group :development, :test do
   gem "rspec-rails"
 end
+```
 
 Shoulda will automatically include matchers into the appropriate example groups.