Fix Rack::Lock to set env['rack.multithread'] properly

* The original code would set the flag for the duration of
  Rack::Lock#call and then set it back when the method finished. The
  problem is that the BodyProxy could be executing code that relies on
  the state of the flag.

  This change makes sure the application *and* the body proxy see the
  expected state of the environment.

1 files changed, 14 insertions, 1 deletions

diff --git a/test/spec_lock.rb b/test/spec_lock.rb
index 4a44a0b4..099e806c 100644
--- a/test/spec_lock.rb
+++ b/test/spec_lock.rb
@@ -149,7 +149,10 @@ describe Rack::Lock do
       env['rack.multithread'].should.equal false
       [200, {"Content-Type" => "text/plain"}, %w{ a b c }]
     }, false)
-    app.call(Rack::MockRequest.env_for("/"))
+    env = Rack::MockRequest.env_for("/")
+    env['rack.multithread'].should.equal true
+    app.call(env)
+    env['rack.multithread'].should.equal true
   end
 
   should "reset original multithread flag when exiting lock" do
@@ -174,4 +177,14 @@ describe Rack::Lock do
     lambda { app.call(env) }.should.raise(Exception)
     lock.unlocked?.should.equal false
   end
+
+  should "not reset the environment while the body is proxied" do
+    proxy = Class.new do
+      attr_reader :env
+      def initialize(env) @env = env end
+    end
+    app = Rack::Lock.new lambda { |env| [200, {"Content-Type" => "text/plain"}, proxy.new(env)] }
+    response = app.call(Rack::MockRequest.env_for("/"))[2]
+    response.env['rack.multithread'].should.equal false
+  end
 end