Preserve redirect_url query parameters for transparent redirect.

NEWS.md

@@ -3,6 +3,8 @@
 * Braintree::Transaction.void updates the existing sale transaction instead of
   creating a new transaction of type Braintree::Transaction::Status::Voided
 
+* Preserve `redirect_url` query parameters for transparent redirect (#36)
+
 # 0.2.1
 * Fake refunds via `Braintree::Transaction.refund` and
   `Braintree::CreditCard.refund`.

lib/fake_braintree/redirect.rb

@@ -32,7 +32,10 @@ def confirm
     private
 
     def uri
-      URI.parse(@transparent_data['redirect_url']).merge("?#{base_query}&hash=#{hash(base_query)}")
+      uri = URI.parse(@transparent_data['redirect_url'])
+      merged_query = [uri.query, base_query].compact.join('&')
+      uri.query = "#{merged_query}&hash=#{hash(merged_query)}"
+      uri
     end
 
     def base_query

spec/fake_braintree/transparent_redirect_spec.rb

@@ -15,6 +15,19 @@
       params[:kind].should_not be_nil
     end
 
+    it "preserves redirect_url query parameters" do
+      redirect_url = 'http://example.com/redirect_path?preserve=me'
+
+      response = post_transparent_redirect(
+        :create_customer_data,
+        :redirect_url => redirect_url,
+        :customer => build_customer_hash
+      )
+
+      params = parse_redirect(response)
+      params[:preserve].should == 'me'
+    end
+
     it 'rejects submissions without transparent redirect data' do
       response = post_transparent_redirect_without_data
       response.code.should == '422'