make sure request parameters are accessible after rack throws an exception...

make sure request parameters are accessible after rack throws an exception parsing the query string [#3030 state:resolved]
Signed-off-by: NJosé Valim <jose.valim@gmail.com>

actionpack/lib/action_dispatch/http/request.rb

@@ -214,13 +214,13 @@ def session_options=(options)
 
     # Override Rack's GET method to support indifferent access
     def GET
-      @env["action_dispatch.request.query_parameters"] ||= normalize_parameters(super)
+      @env["action_dispatch.request.query_parameters"] ||= (normalize_parameters(super) || {})
     end
     alias :query_parameters :GET
 
     # Override Rack's POST method to support indifferent access
     def POST
-      @env["action_dispatch.request.request_parameters"] ||= normalize_parameters(super)
+      @env["action_dispatch.request.request_parameters"] ||= (normalize_parameters(super) || {})
     end
     alias :request_parameters :POST
 

actionpack/test/dispatch/request_test.rb

@@ -385,6 +385,18 @@ class RequestTest < ActiveSupport::TestCase
     assert_equal({"bar" => 2}, request.query_parameters)
   end
 
+  test "parameters still accessible after rack parse error" do
+    mock_rack_env = { "QUERY_STRING" => "x[y]=1&x[y][][w]=2", "rack.input" => "foo" }
+    request = nil
+    begin
+      request = stub_request(mock_rack_env) 
+      request.parameters
+    rescue TypeError => e
+      # rack will raise a TypeError when parsing this query string
+    end
+    assert_equal({}, request.parameters)
+  end
+
   test "formats with accept header" do
     request = stub_request 'HTTP_ACCEPT' => 'text/html'
     request.expects(:parameters).at_least_once.returns({})