lint: avoid TypeError on non-Hash-like response headers lint-headerhash

According to SPEC (and check_headers), Response headers need only
respond to #each.  Thus, check_hijack_response should rely on
Rack::Utils::HeaderHash if it wishes to access the headers in a
hash-like fashion.

2 files changed, 12 insertions, 0 deletions

diff --git a/lib/rack/lint.rb b/lib/rack/lint.rb
index 338f7f09..1bc2127f 100644
--- a/lib/rack/lint.rb
+++ b/lib/rack/lint.rb
@@ -500,6 +500,11 @@ module Rack
     ## It is also possible to hijack a response after the status and headers
     ## have been sent.
     def check_hijack_response(headers, env)
+
+      # this check uses headers like a hash, but the spec only requires
+      # headers respond to #each
+      headers = Rack::Utils::HeaderHash.new(headers)
+
       ## In order to do this, an application may set the special header
       ## <tt>rack.hijack</tt> to an object that responds to <tt>call</tt>
       ## accepting an argument that conforms to the <tt>rack.hijack_io</tt>
diff --git a/test/spec_lint.rb b/test/spec_lint.rb
index f824113f..fb60b7ef 100644
--- a/test/spec_lint.rb
+++ b/test/spec_lint.rb
@@ -231,6 +231,13 @@ describe Rack::Lint do
                        [200, {"Foo-Bar" => "one\ntwo\nthree", "Content-Length" => "0", "Content-Type" => "text/plain" }, []]
                      }).call(env({}))
     }.should.not.raise(Rack::Lint::LintError)
+
+    # non-Hash header responses should be allowed
+    lambda {
+      Rack::Lint.new(lambda { |env|
+                       [200, [%w(Content-Type text/plain), %w(Content-Length 0)], []]
+                     }).call(env({}))
+    }.should.not.raise(TypeError)
   end
 
   should "notice content-type errors" do