Allow lower case escapes in URI

See RFC 2396 2.4.1
Closes #1857

Author: ericmj

lib/elixir/lib/uri.ex

@@ -137,6 +137,7 @@ defmodule URI do
   def decode(<<>>), do: <<>>
 
   defp hex2dec(n) when n in ?A..?F, do: n - ?A + 10
+  defp hex2dec(n) when n in ?a..?f, do: n - ?a + 10
   defp hex2dec(n) when n in ?0..?9, do: n - ?0
 
   defp check_plus(?+), do: 32

lib/elixir/test/elixir/uri_test.exs

@@ -155,7 +155,7 @@ defmodule URITest do
       port_uri = URI.parse("http://[#{addr}]:2222/")
       assert port_uri.host == addr
       assert port_uri.port == 2222
-      
+
       userinfo_port_uri = URI.parse("http://user:pass@[#{addr}]:2222/")
       assert userinfo_port_uri.host == addr
       assert userinfo_port_uri.userinfo == "user:pass"
@@ -176,4 +176,9 @@ defmodule URITest do
     assert to_string(URI.parse("http://google.com?q=lol")) == "http://google.com?q=lol"
     assert to_string(URI.parse("http://google.com?q=lol#omg")) == "http://google.com?q=lol#omg"
   end
+
+  test :escape do
+    assert URI.decode("%2f%41%4a%55") == "/AJU"
+    assert URI.decode("%2F%41%4A%55") == "/AJU"
+  end
 end