Add RewindableInput wrapper to fix issues with middleware that impolitely eat up non-rewindable input

1 files changed, 37 insertions, 0 deletions

diff --git a/actionpack/test/controller/request/url_encoded_params_parsing_test.rb b/actionpack/test/controller/request/url_encoded_params_parsing_test.rb
index 26a4538ca6..b162796e5b 100644
--- a/actionpack/test/controller/request/url_encoded_params_parsing_test.rb
+++ b/actionpack/test/controller/request/url_encoded_params_parsing_test.rb
@@ -150,8 +150,45 @@ class UrlEncodedParamsParsingTest < ActionController::IntegrationTest
     assert_parses expected, query
   end
 
+  test "passes through rack middleware and parses params" do
+    with_muck_middleware do
+      assert_parses({ "a" => { "b" => "c" } }, "a[b]=c")
+    end
+  end
+
+  # The lint wrapper is used in integration tests
+  # instead of a normal StringIO class
+  InputWrapper = Rack::Lint::InputWrapper
+
+  test "passes through rack middleware and parses params with unwindable input" do
+    InputWrapper.any_instance.stubs(:rewind).raises(Errno::ESPIPE)
+    with_muck_middleware do
+      assert_parses({ "a" => { "b" => "c" } }, "a[b]=c")
+    end
+  end
 
   private
+    class MuckMiddleware
+      def initialize(app)
+        @app = app
+      end
+
+      def call(env)
+        req = Rack::Request.new(env)
+        req.params # Parse params
+        @app.call(env)
+      end
+    end
+
+    def with_muck_middleware
+      original_middleware = ActionController::Dispatcher.middleware
+      middleware = original_middleware.dup
+      middleware.use MuckMiddleware
+      ActionController::Dispatcher.middleware = middleware
+      yield
+      ActionController::Dispatcher.middleware = original_middleware
+    end
+
     def with_test_routing
       with_routing do |set|
         set.draw do |map|