Use request cookie jar as basis for response.

Refactor response cookie handling to use our new Request#cookie_jar.
Instead of creating a jar from scratch, make a copy of the request's
cookie jar and populate it with any additional cookies from the response
headers.

Also refactor the redirection code to use this cookie jar, which solves
the question of how to handle cookies from the original request.

lib/restclient/abstract_response.rb

@@ -39,11 +39,20 @@ module RestClient
       history
     end
 
-    # Hash of cookies extracted from response headers
+    # Hash of cookies extracted from response headers.
+    #
+    # NB: This will return only cookies whose domain matches this request, and
+    # may not even return all of those cookies if there are duplicate names.
+    # Use the full cookie_jar for more nuanced access.
+    #
+    # @see #cookie_jar
+    #
+    # @return [Hash]
+    #
     def cookies
       hash = {}
 
-      cookie_jar.cookies.each do |cookie|
+      cookie_jar.cookies(@request.uri).each do |cookie|
         hash[cookie.name] = cookie.value
       end
 
@@ -57,7 +66,7 @@ module RestClient
     def cookie_jar
       return @cookie_jar if @cookie_jar
 
-      jar = HTTP::CookieJar.new
+      jar = @request.cookie_jar.dup
       headers.fetch(:set_cookie, []).each do |cookie|
         jar.parse(cookie, @request.uri)
       end
@@ -185,10 +194,8 @@ module RestClient
       new_args[:headers] = request.headers
       new_args[:max_redirects] = request.max_redirects - 1
 
-      # TODO: figure out what to do with original :cookie, :cookies values
-      new_args[:headers]['Cookie'] = HTTP::Cookie.cookie_value(
-        cookie_jar.cookies(new_args.fetch(:url)))
-
+      # pass through our new cookie jar
+      new_args[:cookies] = cookie_jar
 
       # prepare new request
       new_req = Request.new(new_args)

spec/helpers.rb

@@ -16,7 +16,7 @@ module Helpers
 
   def request_double(url: 'http://example.com', method: 'get')
     double('request', url: url, uri: URI.parse(url), method: method,
-           user: nil, password: nil,
+           user: nil, password: nil, cookie_jar: HTTP::CookieJar.new,
            redirection_history: nil, args: {url: url, method: method})
   end
 end

spec/unit/abstract_response_spec.rb

@@ -92,7 +92,8 @@ describe RestClient::AbstractResponse, :include_helpers do
     it 'handles cookies when URI scheme is implicit' do
       net_http_res = double('net http response')
       net_http_res.should_receive(:to_hash).and_return('set-cookie' => ['session_id=1; path=/'])
-      request = double(url: 'example.com', uri: URI.parse('http://example.com'), method: 'get')
+      request = double(url: 'example.com', uri: URI.parse('http://example.com'),
+                       method: 'get', cookie_jar: HTTP::CookieJar.new)
       response = MyAbstractResponse.new(net_http_res, request)
       response.cookie_jar.should be_a HTTP::CookieJar
 

spec/unit/response_spec.rb

@@ -120,10 +120,13 @@ describe RestClient::Response, :include_helpers do
       RestClient::Request.execute(:url => 'http://some/resource', :method => :get).body.should eq 'Qux'
     end
 
-    it 'does not keep cookies across domains' do
-      stub_request(:get, 'http://some/resource').to_return(:body => '', :status => 301, :headers => {'Set-Cookie' => 'Foo=Bar', 'Location' => 'http://new/resource', })
-      stub_request(:get, 'http://new/resource').with(:headers => {'Cookie' => ''}).to_return(:body => 'Qux')
-      RestClient::Request.execute(:url => 'http://some/resource', :method => :get).body.should eq 'Qux'
+    it 'respects cookie domains on redirect' do
+      stub_request(:get, 'http://some.example.com/').to_return(:body => '', :status => 301,
+        :headers => {'Set-Cookie' => 'Foo=Bar', 'Location' => 'http://new.example.com/', })
+      stub_request(:get, 'http://new.example.com/').with(
+        :headers => {'Cookie' => 'passedthrough=1'}).to_return(:body => 'Qux')
+
+      RestClient::Request.execute(:url => 'http://some.example.com/', :method => :get, cookies: [HTTP::Cookie.new('passedthrough', '1', domain: 'new.example.com', path: '/')]).body.should eq 'Qux'
     end
 
     it "doesn't follow a 301 when the request is a post" do