Return an empty string for Request#host if HTTP_HOST and SERVER_NAME are both missing

2 files changed, 6 insertions, 1 deletions

diff --git a/lib/rack/request.rb b/lib/rack/request.rb
index 4c4cf61a..248ce18d 100644
--- a/lib/rack/request.rb
+++ b/lib/rack/request.rb
@@ -65,7 +65,7 @@ module Rack
 
     def host
       # Remove port number.
-      (@env["HTTP_HOST"] || @env["SERVER_NAME"]).gsub(/:\d+\z/, '')
+      (@env["HTTP_HOST"] || @env["SERVER_NAME"]).to_s.gsub(/:\d+\z/, '')
     end
 
     def script_name=(s); @env["SCRIPT_NAME"] = s.to_s             end
diff --git a/test/spec_rack_request.rb b/test/spec_rack_request.rb
index 81f05eba..facbe753 100644
--- a/test/spec_rack_request.rb
+++ b/test/spec_rack_request.rb
@@ -37,6 +37,11 @@ context "Rack::Request" do
     req = Rack::Request.new \
       Rack::MockRequest.env_for("/", "SERVER_NAME" => "example.org:9292")
     req.host.should.equal "example.org"
+
+    env = Rack::MockRequest.env_for("/")
+    env.delete("SERVER_NAME")
+    req = Rack::Request.new(env)
+    req.host.should.equal ""
   end
 
   specify "can parse the query string" do