Merge pull request sporkmonger#387 from isqad/master

fix: avoid some allocations of strings

lib/addressable/uri.rb

@@ -82,7 +82,7 @@ module NormalizeCharacterClasses
       "wais" => 210,
       "ldap" => 389,
       "prospero" => 1525
-    }
+    }.freeze
 
     ##
     # Returns a URI object based on the parsed string.
@@ -472,7 +472,11 @@ def self.unencode(uri, return_type=String, leave_encoded='')
       uri = uri.dup
       # Seriously, only use UTF-8. I'm really not kidding!
       uri.force_encoding("utf-8")
-      leave_encoded = leave_encoded.dup.force_encoding("utf-8")
+
+      unless leave_encoded.empty?
+        leave_encoded = leave_encoded.dup.force_encoding("utf-8")
+      end
+
       result = uri.gsub(/%[0-9a-f]{2}/iu) do |sequence|
         c = sequence[1..3].to_i(16).chr
         c.force_encoding("utf-8")
@@ -563,7 +567,11 @@ def self.normalize_component(component, character_class=
           end.flatten.join('|')})"
         end
 
-        character_class = /[^#{character_class}]#{leave_re}/
+        character_class = if leave_re
+                            /[^#{character_class}]#{leave_re}/
+                          else
+                            /[^#{character_class}]/
+                          end
       end
       # We can't perform regexps on invalid UTF sequences, but
       # here we need to, so switch to ASCII.
@@ -1123,6 +1131,7 @@ def host
     # @return [String] The host component, normalized.
     def normalized_host
       return nil unless self.host
+
       @normalized_host ||= begin
         if !self.host.strip.empty?
           result = ::Addressable::IDNA.to_ascii(
@@ -1142,7 +1151,9 @@ def normalized_host
         end
       end
       # All normalized values should be UTF-8
-      @normalized_host.force_encoding(Encoding::UTF_8) if @normalized_host
+      if @normalized_host && !@normalized_host.empty?
+        @normalized_host.force_encoding(Encoding::UTF_8)
+      end
       @normalized_host
     end