diff --git a/Rakefile b/Rakefile
index 76f4c08..7d3dbd7 100755
--- a/Rakefile
+++ b/Rakefile
@@ -1,16 +1,12 @@
 #!/usr/bin/env rake
 
 require 'bundler/gem_tasks'
-require 'rake/testtask'
+require 'rspec/core/rake_task'
 require 'yard'
 
-Rake::TestTask.new do |test|
-  test.libs << 'lib' << 'test'
-  test.pattern = 'test/**/*_test.rb'
-  test.verbose = true
-end
+RSpec::Core::RakeTask.new(:spec)
 
-task :default => :test
+task :default => :spec
 
 namespace :doc do
   YARD::Rake::YardocTask.new do |task|
diff --git a/lib/simple_oauth/header.rb b/lib/simple_oauth/header.rb
index 5420702..60182a3 100644
--- a/lib/simple_oauth/header.rb
+++ b/lib/simple_oauth/header.rb
@@ -101,7 +101,7 @@ module SimpleOAuth
     end
 
     def url_params
-      CGI.parse(@uri.query || '').inject([]){|p,(k,vs)| p + vs.map{|v| [k, v] } }
+      CGI.parse(@uri.query || '').inject([]){|p,(k,vs)| p + vs.sort.map{|v| [k, v] } }
     end
 
     def rsa_sha1_signature
diff --git a/simple_oauth.gemspec b/simple_oauth.gemspec
index 718eabe..cf363c3 100644
--- a/simple_oauth.gemspec
+++ b/simple_oauth.gemspec
@@ -10,9 +10,8 @@ Gem::Specification.new do |gem|
   gem.summary     = gem.description
   gem.homepage    = 'https://github.com/laserlemon/simple_oauth'
 
-  gem.add_development_dependency 'minitest'
-  gem.add_development_dependency 'mocha', '~> 0.10.0'
   gem.add_development_dependency 'rake'
+  gem.add_development_dependency 'rspec', '~> 2.0'
   gem.add_development_dependency 'simplecov'
   gem.add_development_dependency 'yard'
 
diff --git a/spec/simple_oauth/header_spec.rb b/spec/simple_oauth/header_spec.rb
new file mode 100644
index 0000000..e962ad8
--- /dev/null
+++ b/spec/simple_oauth/header_spec.rb
@@ -0,0 +1,354 @@
+#  encoding: utf-8
+
+require 'spec_helper'
+
+describe SimpleOAuth::Header do
+  describe '.default_options' do
+    let(:default_options){ SimpleOAuth::Header.default_options }
+
+    it 'is different every time' do
+      SimpleOAuth::Header.default_options.should_not == default_options
+    end
+
+    it 'is used for new headers' do
+      SimpleOAuth::Header.stub(:default_options => default_options)
+      header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friendships.json', {})
+      header.options.should == default_options
+    end
+
+    it 'includes a signature method and an OAuth version' do
+      default_options[:signature_method].should_not be_nil
+      default_options[:version].should_not be_nil
+    end
+  end
+
+  describe '.encode' do
+    it 'encodes (most) non-word characters' do
+      [' ', '!', '@', '#', '$', '%', '^', '&'].each do |character|
+        encoded = SimpleOAuth::Header.encode(character)
+        encoded.should_not == character
+        encoded.should == URI.encode(character, /.*/)
+      end
+    end
+
+    it 'does not encode - . or ~' do
+      ['-', '.', '~'].each do |character|
+        encoded = SimpleOAuth::Header.encode(character)
+        encoded.should == character
+      end
+    end
+
+    def self.test_special_characters
+      it 'encodes non-ASCII characters' do
+        SimpleOAuth::Header.encode('é').should == '%C3%A9'
+      end
+
+      it 'encodes multibyte characters' do
+        SimpleOAuth::Header.encode('あ').should == '%E3%81%82'
+      end
+    end
+
+    if RUBY_VERSION >= '1.9'
+      test_special_characters
+    else
+      %w(n N e E s S u U).each do |kcode|
+        describe %(when $KCODE = "#{kcode}") do
+          original_kcode = $KCODE
+          begin
+            $KCODE = kcode
+            test_special_characters
+          ensure
+            $KCODE = original_kcode
+          end
+        end
+      end
+    end
+  end
+
+  describe '.decode' do
+    pending
+  end
+
+  describe '.parse' do
+    let(:header){ SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friends.json', {}) }
+    let(:parsed_options){ SimpleOAuth::Header.parse(header) }
+
+    it 'returns a hash' do
+      parsed_options.should be_a(Hash)
+    end
+
+    it 'includes the options used to build the header' do
+      parsed_options.reject{|k,_| k == :signature }.should == header.options
+    end
+
+    it 'includes a signature' do
+      header.options.should_not have_key(:signature)
+      parsed_options.should have_key(:signature)
+      parsed_options[:signature].should_not be_nil
+    end
+  end
+
+  describe '#initialize' do
+    let(:header){ SimpleOAuth::Header.new(:get, 'HTTPS://api.TWITTER.com:443/1/statuses/friendships.json?foo=bar#anchor', {}) }
+
+    it 'stringifies and uppercases the request method' do
+      header.method.should == 'GET'
+    end
+
+    it 'downcases the scheme and authority' do
+      header.url.should =~ %r(^https://api\.twitter\.com/)
+    end
+
+    it 'ignores the query and fragment' do
+      header.url.should =~ %r(/1/statuses/friendships\.json$)
+    end
+  end
+
+  describe '#valid?' do
+    context 'using the HMAC-SHA1 signature method' do
+      it 'requires consumer and token secrets' do
+        secrets = {:consumer_secret => 'CONSUMER_SECRET', :token_secret => 'TOKEN_SECRET'}
+        header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friends.json', {}, secrets)
+        parsed_header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friends.json', {}, header)
+        parsed_header.should_not be_valid
+        parsed_header.should be_valid(secrets)
+      end
+    end
+
+    context 'using the RSA-SHA1 signature method' do
+      it 'requires an identical private key' do
+        secrets = {:consumer_secret => rsa_private_key}
+        header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friends.json', {}, secrets.merge(:signature_method => 'RSA-SHA1'))
+        parsed_header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friends.json', {}, header)
+        expect{ parsed_header.valid? }.to raise_error(TypeError)
+        parsed_header.should be_valid(secrets)
+      end
+    end
+
+    context 'using the RSA-SHA1 signature method' do
+      it 'requires consumer and token secrets' do
+        secrets = {:consumer_secret => 'CONSUMER_SECRET', :token_secret => 'TOKEN_SECRET'}
+        header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friends.json', {}, secrets.merge(:signature_method => 'PLAINTEXT'))
+        parsed_header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friends.json', {}, header)
+        parsed_header.should_not be_valid
+        parsed_header.should be_valid(secrets)
+      end
+    end
+  end
+
+  describe '#normalized_attributes' do
+    let(:header){ SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friends.json', {}) }
+    let(:normalized_attributes){ header.send(:normalized_attributes) }
+
+    it 'returns a sorted-key, quoted-value and comma-separated list' do
+      header.stub(:signed_attributes => {:d => 1, :c => 2, :b => 3, :a => 4})
+      normalized_attributes.should == 'a="4", b="3", c="2", d="1"'
+    end
+
+    it 'url-encodes its values' do
+      header.stub(:signed_attributes => {1 => '!', 2 => '@', 3 => '#', 4 => '$'})
+      normalized_attributes.should == '1="%21", 2="%40", 3="%23", 4="%24"'
+    end
+  end
+
+  describe '#signed_attributes' do
+    it 'includes the OAuth signature' do
+      header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friends.json', {})
+      header.send(:signed_attributes).should have_key(:oauth_signature)
+    end
+  end
+
+  describe '#attributes' do
+    let(:header) do
+      options = {}
+      SimpleOAuth::Header::ATTRIBUTE_KEYS.each{|k| options[k] = k.to_s.upcase }
+      options[:other] = 'OTHER'
+      SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friendships.json', {}, options)
+    end
+    let(:attributes){ header.send(:attributes) }
+
+    it 'prepends keys with "oauth_"' do
+      attributes.keys.should be_all{|k| k.to_s =~ /^oauth_/ }
+    end
+
+    it 'excludes keys not included in the list of valid attributes' do
+      attributes.keys.should be_all{|k| k.is_a?(Symbol) }
+      attributes.should_not have_key(:oauth_other)
+    end
+
+    it 'preserves values for valid keys' do
+      attributes.size.should == SimpleOAuth::Header::ATTRIBUTE_KEYS.size
+      attributes.should be_all{|k,v| k.to_s == "oauth_#{v.downcase}" }
+    end
+  end
+
+  describe '#signature' do
+    context 'calls the appropriate signature method' do
+      specify 'when using HMAC-SHA1' do
+        header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friends.json', {}, :signature_method => 'HMAC-SHA1')
+        header.should_receive(:hmac_sha1_signature).once.and_return('HMAC_SHA1_SIGNATURE')
+        header.send(:signature).should == 'HMAC_SHA1_SIGNATURE'
+      end
+
+      specify 'when using RSA-SHA1' do
+        header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friends.json', {}, :signature_method => 'RSA-SHA1')
+        header.should_receive(:rsa_sha1_signature).once.and_return('RSA_SHA1_SIGNATURE')
+        header.send(:signature).should == 'RSA_SHA1_SIGNATURE'
+      end
+
+      specify 'when using PLAINTEXT' do
+        header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friends.json', {}, :signature_method => 'PLAINTEXT')
+        header.should_receive(:plaintext_signature).once.and_return('PLAINTEXT_SIGNATURE')
+        header.send(:signature).should == 'PLAINTEXT_SIGNATURE'
+      end
+    end
+  end
+
+  describe '#hmac_sha1_signature' do
+    it 'reproduces a successful Twitter GET' do
+      options = {
+        :consumer_key => '8karQBlMg6gFOwcf8kcoYw',
+        :consumer_secret => '3d0vcHyUiiqADpWxolW8nlDIpSWMlyK7YNgc5Qna2M',
+        :nonce => '547fed103e122eecf84c080843eedfe6',
+        :signature_method => 'HMAC-SHA1',
+        :timestamp => '1286830180',
+        :token => '201425800-Sv4sTcgoffmHGkTCue0JnURT8vrm4DiFAkeFNDkh',
+        :token_secret => 'T5qa1tF57tfDzKmpM89DHsNuhgOY4NT6DlNLsTFcuQ'
+      }
+      header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friends.json', {}, options)
+      header.to_s.should == 'OAuth oauth_consumer_key="8karQBlMg6gFOwcf8kcoYw", oauth_nonce="547fed103e122eecf84c080843eedfe6", oauth_signature="i9CT6ahDRAlfGX3hKYf78QzXsaw%3D", oauth_signature_method="HMAC-SHA1", oauth_timestamp="1286830180", oauth_token="201425800-Sv4sTcgoffmHGkTCue0JnURT8vrm4DiFAkeFNDkh", oauth_version="1.0"'
+    end
+
+    it 'reproduces a successful Twitter POST' do
+      options = {
+        :consumer_key => '8karQBlMg6gFOwcf8kcoYw',
+        :consumer_secret => '3d0vcHyUiiqADpWxolW8nlDIpSWMlyK7YNgc5Qna2M',
+        :nonce => 'b40a3e0f18590ecdcc0e273f7d7c82f8',
+        :signature_method => 'HMAC-SHA1',
+        :timestamp => '1286830181',
+        :token => '201425800-Sv4sTcgoffmHGkTCue0JnURT8vrm4DiFAkeFNDkh',
+        :token_secret => 'T5qa1tF57tfDzKmpM89DHsNuhgOY4NT6DlNLsTFcuQ'
+      }
+      header = SimpleOAuth::Header.new(:post, 'https://api.twitter.com/1/statuses/update.json', {:status => 'hi, again'}, options)
+      header.to_s.should == 'OAuth oauth_consumer_key="8karQBlMg6gFOwcf8kcoYw", oauth_nonce="b40a3e0f18590ecdcc0e273f7d7c82f8", oauth_signature="mPqSFKejrWWk3ZT9bTQjhO5b2xI%3D", oauth_signature_method="HMAC-SHA1", oauth_timestamp="1286830181", oauth_token="201425800-Sv4sTcgoffmHGkTCue0JnURT8vrm4DiFAkeFNDkh", oauth_version="1.0"'
+    end
+  end
+
+  describe '#secret' do
+    let(:header){ SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friendships.json', {}) }
+    let(:secret){ header.send(:secret) }
+
+    it 'combines the consumer and token secrets with an ampersand' do
+      header.stub(:options => {:consumer_secret => 'CONSUMER_SECRET', :token_secret => 'TOKEN_SECRET'})
+      secret.should == 'CONSUMER_SECRET&TOKEN_SECRET'
+    end
+
+    it 'URL encodes each secret value before combination' do
+      header.stub(:options => {:consumer_secret => 'CONSUM#R_SECRET', :token_secret => 'TOKEN_S#CRET'})
+      secret.should == 'CONSUM%23R_SECRET&TOKEN_S%23CRET'
+    end
+  end
+
+  describe '#signature_base' do
+    let(:header){ SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friendships.json', {}) }
+    let(:signature_base){ header.send(:signature_base) }
+
+    it 'combines the request method, URL and normalized parameters using ampersands' do
+      header.stub(:method => 'METHOD', :url => 'URL', :normalized_params => 'NORMALIZED_PARAMS')
+      signature_base.should == 'METHOD&URL&NORMALIZED_PARAMS'
+    end
+
+    it 'URL encodes each value before combination' do
+      header.stub(:method => 'ME#HOD', :url => 'U#L', :normalized_params => 'NORMAL#ZED_PARAMS')
+      signature_base.should == 'ME%23HOD&U%23L&NORMAL%23ZED_PARAMS'
+    end
+  end
+
+  describe '#normalized_params' do
+    let(:header) do
+      header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friendships.json', {})
+      header.stub(:signature_params => [['A', '4'], ['B', '3'], ['B', '2'], ['C', '1'], ['D[]', '0 ']])
+      header
+    end
+    let(:signature_params){ header.send(:signature_params) }
+    let(:normalized_params){ header.send(:normalized_params) }
+
+    it 'joins key/value pairs with equal signs and ampersands' do
+      normalized_params.should be_a(String)
+      parts = normalized_params.split('&')
+      parts.size.should == signature_params.size
+      pairs = parts.map{|p| p.split('=') }
+      pairs.should be_all{|p| p.size == 2 }
+    end
+  end
+
+  describe '#signature_params' do
+    let(:header){ SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friendships.json', {}) }
+    let(:signature_params){ header.send(:signature_params) }
+
+    it 'combines OAuth header attributes, body parameters and URL parameters into an flattened array of key/value pairs' do
+      header.stub(
+        :attributes => {:attribute => 'ATTRIBUTE'},
+        :params => {'param' => 'PARAM'},
+        :url_params => [['url_param', '1'], ['url_param', '2']]
+      )
+      signature_params.should == [
+        [:attribute, 'ATTRIBUTE'],
+        ['param', 'PARAM'],
+        ['url_param', '1'],
+        ['url_param', '2']
+      ]
+    end
+  end
+
+  describe '#url_params' do
+    it 'returns an empty array when the URL has no query parameters' do
+      header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friendships.json', {})
+      header.send(:url_params).should == []
+    end
+
+    it 'returns an array of key/value pairs for each query parameter' do
+      header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friendships.json?test=TEST', {})
+      header.send(:url_params).should == [['test', 'TEST']]
+    end
+
+    it 'sorts values for repeated keys' do
+      header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friendships.json?test=3&test=1&test=2', {})
+      header.send(:url_params).should == [['test', '1'], ['test', '2'], ['test', '3']]
+    end
+  end
+
+  describe '#rsa_sha1_signature' do
+    it 'reproduces a successful OAuth example GET' do
+      options = {
+        :consumer_key => 'dpf43f3p2l4k3l03',
+        :consumer_secret => rsa_private_key,
+        :nonce => '13917289812797014437',
+        :signature_method => 'RSA-SHA1',
+        :timestamp => '1196666512'
+      }
+      header = SimpleOAuth::Header.new(:get, 'http://photos.example.net/photos', {:file => 'vacaction.jpg', :size => 'original'}, options)
+      header.to_s.should == 'OAuth oauth_consumer_key="dpf43f3p2l4k3l03", oauth_nonce="13917289812797014437", oauth_signature="jvTp%2FwX1TYtByB1m%2BPbyo0lnCOLIsyGCH7wke8AUs3BpnwZJtAuEJkvQL2%2F9n4s5wUmUl4aCI4BwpraNx4RtEXMe5qg5T1LVTGliMRpKasKsW%2F%2Fe%2BRinhejgCuzoH26dyF8iY2ZZ%2F5D1ilgeijhV%2FvBka5twt399mXwaYdCwFYE%3D", oauth_signature_method="RSA-SHA1", oauth_timestamp="1196666512", oauth_version="1.0"'
+    end
+  end
+
+  describe '#private_key' do
+    pending
+  end
+
+  describe '#plaintext_signature' do
+    it 'reproduces a successful OAuth example GET' do
+      options = {
+        :consumer_key => 'abcd',
+        :consumer_secret => 'efgh',
+        :nonce => 'oLKtec51GQy',
+        :signature_method => 'PLAINTEXT',
+        :timestamp => '1286977095',
+        :token => 'ijkl',
+        :token_secret => 'mnop'
+      }
+      header = SimpleOAuth::Header.new(:get, 'http://host.net/resource?name=value', {:name => 'value'}, options)
+      header.to_s.should == 'OAuth oauth_consumer_key="abcd", oauth_nonce="oLKtec51GQy", oauth_signature="efgh%26mnop", oauth_signature_method="PLAINTEXT", oauth_timestamp="1286977095", oauth_token="ijkl", oauth_version="1.0"'
+    end
+  end
+end
diff --git a/test/helper.rb b/spec/spec_helper.rb
similarity index 52%
rename from test/helper.rb
rename to spec/spec_helper.rb
index b05409a..f725354 100644
--- a/test/helper.rb
+++ b/spec/spec_helper.rb
@@ -3,8 +3,6 @@ unless ENV['CI']
   SimpleCov.start
 end
 
-require 'bundler'
-Bundler.setup
-require 'test/unit'
-require 'mocha'
 require 'simple_oauth'
+
+Dir[File.expand_path('../support/**/*.rb', __FILE__)].each{|f| require f }
diff --git a/test/rsa_private_key b/spec/support/fixtures/rsa-private-key
similarity index 100%
rename from test/rsa_private_key
rename to spec/support/fixtures/rsa-private-key
diff --git a/spec/support/rsa.rb b/spec/support/rsa.rb
new file mode 100644
index 0000000..0d3f116
--- /dev/null
+++ b/spec/support/rsa.rb
@@ -0,0 +1,11 @@
+module RSAHelpers
+  PRIVATE_KEY_PATH = File.expand_path('../fixtures/rsa-private-key', __FILE__)
+
+  def rsa_private_key
+    @rsa_private_key ||= File.read(PRIVATE_KEY_PATH)
+  end
+end
+
+RSpec.configure do |config|
+  config.include RSAHelpers
+end
diff --git a/test/simple_oauth_test.rb b/test/simple_oauth_test.rb
deleted file mode 100644
index ccb8370..0000000
--- a/test/simple_oauth_test.rb
+++ /dev/null
@@ -1,309 +0,0 @@
-# -*- encoding: utf-8 -*-
-require 'helper'
-
-class SimpleOAuthTest < Test::Unit::TestCase
-  def test_default_options
-    # Default header options should change with each call due to generation of
-    # a unique "timestamp" and "nonce" value combination.
-    default_options = SimpleOAuth::Header.default_options
-    assert_not_equal default_options, SimpleOAuth::Header.default_options
-
-    SimpleOAuth::Header.stubs(:default_options).returns(default_options)
-    header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friendships.json', {})
-
-    # Given no options argument, header options defer to the default options.
-    assert_equal default_options, header.options
-
-    # Default options should include a signature method and the OAuth version.
-    assert_equal 'HMAC-SHA1', default_options[:signature_method]
-    assert_equal '1.0', default_options[:version]
-  end
-
-  def test_encode
-    # Non-word characters should be URL encoded...
-    [' ', '!', '@', '#', '$', '%', '^', '&'].each do |character|
-      encoded = SimpleOAuth::Header.encode(character)
-      assert_not_equal character, encoded
-      assert_equal URI.encode(character, /.*/), encoded
-    end
-
-    # ...except for the "-", "." and "~" characters.
-    ['-', '.', '~'].each do |character|
-      assert_equal character, SimpleOAuth::Header.encode(character)
-    end
-
-    major, minor, patch = RUBY_VERSION.split('.')
-    new_ruby = major.to_i >= 2 || major.to_i == 1 && minor.to_i >= 9
-    old_kcode = $KCODE if !new_ruby
-    begin
-      %w(n N e E s S u U).each do |kcode|
-        $KCODE = kcode if !new_ruby
-        assert_equal '%E3%81%82', SimpleOAuth::Header.encode('あ'), "Failed to correctly escape Japanese under $KCODE = #{kcode}"
-        assert_equal '%C3%A9', SimpleOAuth::Header.encode('é'), "Failed to correctly escape e+acute under $KCODE = #{kcode}"
-      end
-    ensure
-      $KCODE = old_kcode if !new_ruby
-    end
-  end
-
-  def test_decode
-    # Pending
-  end
-
-  def test_parse
-    header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friends.json', {})
-    parsed_options = SimpleOAuth::Header.parse(header)
-
-    # Parsed options should be a Hash.
-    assert_kind_of Hash, parsed_options
-
-    # Parsed options should equal the options used to build the header, along
-    # with the additional signature.
-    assert_equal header.options, parsed_options.reject{|k,v| k == :signature }
-  end
-
-  def test_initialize
-    header = SimpleOAuth::Header.new(:get, 'HTTPS://api.TWITTER.com:443/1/statuses/friendships.json#anchor', {})
-
-    # HTTP method should be an uppercase string.
-    #
-    # See: http://oauth.net/core/1.0/#rfc.section.9.1.3
-    assert_equal 'GET', header.method
-
-    # Request URL should downcase the scheme and authority parts as well as
-    # remove the query and fragment parts.
-    #
-    # See: http://oauth.net/core/1.0/#rfc.section.9.1.2
-    assert_equal 'https://api.twitter.com/1/statuses/friendships.json', header.url
-  end
-
-  def test_url
-    # Pending
-  end
-
-  def test_to_s
-    header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friends.json', {})
-    assert_equal "OAuth #{header.send(:normalized_attributes)}", header.to_s
-  end
-
-  def test_valid?
-    # When given consumer and token secrets, those secrets must be passed into
-    # the parsed header validation in order for the validity check to pass.
-    secrets = {:consumer_secret => 'CONSUMER_SECRET', :token_secret => 'TOKEN_SECRET'}
-    header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friends.json', {}, secrets)
-    parsed_header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friends.json', {}, header)
-    assert !parsed_header.valid?
-    assert parsed_header.valid?(secrets)
-
-    # Using the RSA-SHA1 signature method, the consumer secret must be a valid
-    # RSA private key. When parsing the header on the server side, the same
-    # consumer secret must be included in order for the header to validate.
-    secrets = {:consumer_secret => File.read('test/rsa_private_key')}
-    header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friends.json', {}, secrets.merge(:signature_method => 'RSA-SHA1'))
-    parsed_header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friends.json', {}, header)
-    assert_raise(TypeError){ parsed_header.valid? }
-    assert parsed_header.valid?(secrets)
-
-    # Like the default HMAC-RSA1 signature method, the PLAINTEXT method
-    # requires use of both a consumer secret and a token secret. A parsed
-    # header will not validate without these secret values.
-    secrets = {:consumer_secret => 'CONSUMER_SECRET', :token_secret => 'TOKEN_SECRET'}
-    header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friends.json', {}, secrets.merge(:signature_method => 'PLAINTEXT'))
-    parsed_header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friends.json', {}, header)
-    assert !parsed_header.valid?
-    assert parsed_header.valid?(secrets)
-  end
-
-  def test_normalized_attributes
-    header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friends.json', {})
-    header.stubs(:signed_attributes).returns(:d => 1, :c => 2, :b => 3, :a => 4)
-
-    # Should return the OAuth header attributes, sorted by name, with quoted
-    # values and comma-separated.
-    assert_equal 'a="4", b="3", c="2", d="1"', header.send(:normalized_attributes)
-
-    # Values should also be URL encoded.
-    header.stubs(:signed_attributes).returns(1 => '!', 2 => '@', 3 => '#', 4 => '$')
-    assert_equal '1="%21", 2="%40", 3="%23", 4="%24"', header.send(:normalized_attributes)
-  end
-
-  def test_signed_attributes
-    header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friends.json', {})
-    assert header.send(:signed_attributes).keys.include?(:oauth_signature)
-  end
-
-  def test_attributes
-    attribute_options = SimpleOAuth::Header::ATTRIBUTE_KEYS.inject({}){|o,a| o.merge(a => a.to_s.upcase) }
-    options = attribute_options.merge(:other => 'OTHER')
-    header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friendships.json', {}, options)
-    attributes = header.send(:attributes)
-
-    # OAuth header attributes are all to begin with the "oauth_" prefix.
-    assert attributes.all?{|k,v| k.to_s =~ /^oauth_/ }
-
-    # Custom options not included in the list of valid attribute keys should
-    # not be included in the header attributes.
-    assert !attributes.key?(:oauth_other)
-
-    # Valid attribute option values should be preserved.
-    assert_equal attribute_options.size, attributes.size
-    assert attributes.all?{|k,v| k.to_s == "oauth_#{v.downcase}" }
-  end
-
-  def test_signature
-    header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friends.json', {}, :signature_method => 'HMAC-SHA1')
-    header.expects(:hmac_sha1_signature).once.returns('HMAC_SHA1_SIGNATURE')
-    assert_equal 'HMAC_SHA1_SIGNATURE', header.send(:signature)
-
-    header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friends.json', {}, :signature_method => 'RSA-SHA1')
-    header.expects(:rsa_sha1_signature).once.returns('RSA_SHA1_SIGNATURE')
-    assert_equal 'RSA_SHA1_SIGNATURE', header.send(:signature)
-
-    header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friends.json', {}, :signature_method => 'PLAINTEXT')
-    header.expects(:plaintext_signature).once.returns('PLAINTEXT_SIGNATURE')
-    assert_equal 'PLAINTEXT_SIGNATURE', header.send(:signature)
-  end
-
-  def test_hmac_sha1_signature
-    # Reproduce an actual successful call to the Twitter API using the
-    # HMAC-SHA1 signature method, GETting a list of friends.
-    options = {
-      :consumer_key => '8karQBlMg6gFOwcf8kcoYw',
-      :consumer_secret => '3d0vcHyUiiqADpWxolW8nlDIpSWMlyK7YNgc5Qna2M',
-      :nonce => '547fed103e122eecf84c080843eedfe6',
-      #:signature_method => 'HMAC-SHA1',
-      :timestamp => '1286830180',
-      :token => '201425800-Sv4sTcgoffmHGkTCue0JnURT8vrm4DiFAkeFNDkh',
-      :token_secret => 'T5qa1tF57tfDzKmpM89DHsNuhgOY4NT6DlNLsTFcuQ'
-    }
-    successful = 'OAuth oauth_consumer_key="8karQBlMg6gFOwcf8kcoYw", oauth_nonce="547fed103e122eecf84c080843eedfe6", oauth_signature="i9CT6ahDRAlfGX3hKYf78QzXsaw%3D", oauth_signature_method="HMAC-SHA1", oauth_timestamp="1286830180", oauth_token="201425800-Sv4sTcgoffmHGkTCue0JnURT8vrm4DiFAkeFNDkh", oauth_version="1.0"'
-    header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friends.json', {}, options)
-    assert_equal successful, header.to_s
-
-    # Reproduce a successful Twitter call, POSTing a new status.
-    options.merge!(
-      :nonce => 'b40a3e0f18590ecdcc0e273f7d7c82f8',
-      :timestamp => '1286830181'
-    )
-    successful = 'OAuth oauth_consumer_key="8karQBlMg6gFOwcf8kcoYw", oauth_nonce="b40a3e0f18590ecdcc0e273f7d7c82f8", oauth_signature="mPqSFKejrWWk3ZT9bTQjhO5b2xI%3D", oauth_signature_method="HMAC-SHA1", oauth_timestamp="1286830181", oauth_token="201425800-Sv4sTcgoffmHGkTCue0JnURT8vrm4DiFAkeFNDkh", oauth_version="1.0"'
-    header = SimpleOAuth::Header.new(:post, 'https://api.twitter.com/1/statuses/update.json', {:status => 'hi, again'}, options)
-    assert_equal successful, header.to_s
-  end
-
-  def test_secret
-    header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friendships.json', {})
-    header.stubs(:options).returns(:consumer_secret => 'CONSUMER_SECRET', :token_secret => 'TOKEN_SECRET')
-
-    # Should combine the consumer and token secrets with an ampersand.
-    assert_equal 'CONSUMER_SECRET&TOKEN_SECRET', header.send(:secret)
-
-    header.stubs(:options).returns(:consumer_secret => 'CONSUM#R_SECRET', :token_secret => 'TOKEN_S#CRET')
-
-    # Should URL encode each secret value before combination.
-    assert_equal 'CONSUM%23R_SECRET&TOKEN_S%23CRET', header.send(:secret)
-  end
-
-  def test_signature_base
-    header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friendships.json', {})
-    header.stubs(:method).returns('METHOD')
-    header.stubs(:url).returns('URL')
-    header.stubs(:normalized_params).returns('NORMALIZED_PARAMS')
-
-    # Should combine HTTP method, URL and normalized parameters string using
-    # ampersands.
-    assert_equal 'METHOD&URL&NORMALIZED_PARAMS', header.send(:signature_base)
-
-    header.stubs(:method).returns('ME#HOD')
-    header.stubs(:url).returns('U#L')
-    header.stubs(:normalized_params).returns('NORMAL#ZED_PARAMS')
-
-    # Each of the three combined values should be URL encoded.
-    assert_equal 'ME%23HOD&U%23L&NORMAL%23ZED_PARAMS', header.send(:signature_base)
-  end
-
-  def test_normalized_params
-    header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friendships.json', {})
-    header.stubs(:signature_params).returns([['A', '4'], ['B', '3'], ['B', '2'], ['C', '1'], ['D[]', '0 ']])
-
-    # The +normalized_params+ string should join key=value pairs with
-    # ampersands.
-    signature_params = header.send(:signature_params)
-    normalized_params = header.send(:normalized_params)
-    parts = normalized_params.split('&')
-    pairs = parts.map{|p| p.split('=') }
-    assert_kind_of String, normalized_params
-    assert_equal signature_params.size, parts.size
-    assert pairs.all?{|p| p.size == 2 }
-
-    # The signature parameters should be sorted and the keys/values URL encoded
-    # first.
-    assert_equal signature_params.sort_by{|p| p.to_s}, pairs.map{|k, v| [URI.decode(k), URI.decode(v)]}
-  end
-
-  def test_signature_params
-    header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friendships.json', {})
-    header.stubs(:attributes).returns(:attribute => 'ATTRIBUTE')
-    header.stubs(:params).returns('param' => 'PARAM')
-    header.stubs(:url_params).returns([['url_param', '1'], ['url_param', '2']])
-
-    # Should combine OAuth header attributes, body parameters and URL
-    # parameters into an array of key value pairs.
-    signature_params = header.send(:signature_params)
-    assert_kind_of Array, signature_params
-    assert_equal [:attribute, 'param', 'url_param', 'url_param'], signature_params.map{|p| p.first}
-    assert_equal ['ATTRIBUTE', 'PARAM', '1', '2'], signature_params.map{|p| p.last}
-  end
-
-  def test_url_params
-    # A URL with no query parameters should produce empty +url_params+
-    header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friendships.json', {})
-    assert_equal [], header.send(:url_params)
-
-    # A URL with query parameters should return a hash having array values
-    # containing the given query parameters.
-    header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friendships.json?test=TEST', {})
-    url_params = header.send(:url_params)
-    assert_kind_of Array, url_params
-    assert_equal [['test', 'TEST']], url_params
-
-    # If a query parameter is repeated, the values should be sorted.
-    header = SimpleOAuth::Header.new(:get, 'https://api.twitter.com/1/statuses/friendships.json?test=1&test=2', {})
-    assert_equal [['test', '1'], ['test', '2']], header.send(:url_params)
-  end
-
-  def test_rsa_sha1_signature
-    # Sample request taken from:
-    # http://wiki.oauth.net/TestCases
-    options = {
-      :consumer_key => 'dpf43f3p2l4k3l03',
-      :consumer_secret => File.read('test/rsa_private_key'),
-      :nonce => '13917289812797014437',
-      :signature_method => 'RSA-SHA1',
-      :timestamp => '1196666512'
-    }
-    successful = 'OAuth oauth_consumer_key="dpf43f3p2l4k3l03", oauth_nonce="13917289812797014437", oauth_signature="jvTp%2FwX1TYtByB1m%2BPbyo0lnCOLIsyGCH7wke8AUs3BpnwZJtAuEJkvQL2%2F9n4s5wUmUl4aCI4BwpraNx4RtEXMe5qg5T1LVTGliMRpKasKsW%2F%2Fe%2BRinhejgCuzoH26dyF8iY2ZZ%2F5D1ilgeijhV%2FvBka5twt399mXwaYdCwFYE%3D", oauth_signature_method="RSA-SHA1", oauth_timestamp="1196666512", oauth_version="1.0"'
-    header = SimpleOAuth::Header.new(:get, 'http://photos.example.net/photos', {:file => 'vacaction.jpg', :size => 'original'}, options)
-    assert_equal successful, header.to_s
-  end
-
-  def test_private_key
-    # Pending
-  end
-
-  def plaintext_signature
-    # Sample request taken from:
-    # http://oauth.googlecode.com/svn/code/javascript/example/signature.html
-    options = {
-      :consumer_key => 'abcd',
-      :consumer_secret => 'efgh',
-      :nonce => 'oLKtec51GQy',
-      :signature_method => 'PLAINTEXT',
-      :timestamp => '1286977095',
-      :token => 'ijkl',
-      :token_secret => 'mnop'
-    }
-    successful = 'OAuth oauth_consumer_key="abcd", oauth_nonce="oLKtec51GQy", oauth_signature="efgh%26mnop", oauth_signature_method="PLAINTEXT", oauth_timestamp="1286977095", oauth_token="ijkl", oauth_version="1.0"'
-    header = SimpleOAuth::Header.new(:get, 'http://host.net/resource?name=value', {:name => 'value'}, options)
-    assert_equal successful, header.to_s
-  end
-end