http_response: skip Date header case-insensitively

HTTP headers are compared case-insensitively, so we must filter out
the Date header case-insensitively.  Found via casual code
inspection, I doubt anybody sets a Date header in Rack apps.

1 files changed, 1 insertions, 1 deletions

diff --git a/lib/yahns/http_response.rb b/lib/yahns/http_response.rb
index 8965fd0..33ae93e 100644
--- a/lib/yahns/http_response.rb
+++ b/lib/yahns/http_response.rb
@@ -143,7 +143,7 @@ module Yahns::HttpResponse # :nodoc:
       buf = "#{response_start}#{status}\r\nDate: #{httpdate}\r\n"
       headers.each do |key, value|
         case key
-        when %r{\ADate\z}
+        when %r{\ADate\z}i
           next
         when %r{\AContent-Range\z}i
           if %r{\Abytes (\d+)-(\d+)/\d+\z} =~ value