[ruby/cgi] Implement `CGI.url_encode` and `CGI.url_decode`

[Feature #18822]

Ruby is somewhat missing an RFC 3986 compliant escape method.

https://github.com/ruby/cgi/commit/c2729c7f33

1 files changed, 41 insertions, 8 deletions

diff --git a/lib/cgi/util.rb b/lib/cgi/util.rb
index 55e61bf984..5a5c77ac97 100644
--- a/lib/cgi/util.rb
+++ b/lib/cgi/util.rb
@@ -5,24 +5,57 @@ class CGI
   extend Util
 end
 module CGI::Util
-  @@accept_charset="UTF-8" unless defined?(@@accept_charset)
-  # URL-encode a string.
+  @@accept_charset = Encoding::UTF_8 unless defined?(@@accept_charset)
+
+  # URL-encode a string into application/x-www-form-urlencoded.
+  # Space characters (+" "+) are encoded with plus signs (+"+"+)
   #   url_encoded_string = CGI.escape("'Stop!' said Fred")
   #      # => "%27Stop%21%27+said+Fred"
   def escape(string)
     encoding = string.encoding
-    string.b.gsub(/([^ a-zA-Z0-9_.\-~]+)/) do |m|
+    buffer = string.b
+    buffer.gsub!(/([^ a-zA-Z0-9_.\-~]+)/) do |m|
       '%' + m.unpack('H2' * m.bytesize).join('%').upcase
-    end.tr(' ', '+').force_encoding(encoding)
+    end
+    buffer.tr!(' ', '+')
+    buffer.force_encoding(encoding)
   end
 
-  # URL-decode a string with encoding(optional).
+  # URL-decode an application/x-www-form-urlencoded string with encoding(optional).
   #   string = CGI.unescape("%27Stop%21%27+said+Fred")
   #      # => "'Stop!' said Fred"
-  def unescape(string,encoding=@@accept_charset)
-    str=string.tr('+', ' ').b.gsub(/((?:%[0-9a-fA-F]{2})+)/) do |m|
+  def unescape(string, encoding = @@accept_charset)
+    str = string.tr('+', ' ')
+    str = str.b
+    str.gsub!(/((?:%[0-9a-fA-F]{2})+)/) do |m|
+      [m.delete('%')].pack('H*')
+    end
+    str.force_encoding(encoding)
+    str.valid_encoding? ? str : str.force_encoding(string.encoding)
+  end
+
+  # URL-encode a string following RFC 3986
+  # Space characters (+" "+) are encoded with (+"%20"+)
+  #   url_encoded_string = CGI.escape("'Stop!' said Fred")
+  #      # => "%27Stop%21%27%20said%20Fred"
+  def escapeURIComponent(string)
+    encoding = string.encoding
+    buffer = string.b
+    buffer.gsub!(/([^a-zA-Z0-9_.\-~]+)/) do |m|
+      '%' + m.unpack('H2' * m.bytesize).join('%').upcase
+    end
+    buffer.force_encoding(encoding)
+  end
+
+  # URL-decode a string following RFC 3986 with encoding(optional).
+  #   string = CGI.unescape("%27Stop%21%27+said%20Fred")
+  #      # => "'Stop!'+said Fred"
+  def unescapeURIComponent(string, encoding = @@accept_charset)
+    str = string.b
+    str.gsub!(/((?:%[0-9a-fA-F]{2})+)/) do |m|
       [m.delete('%')].pack('H*')
-    end.force_encoding(encoding)
+    end
+    str.force_encoding(encoding)
     str.valid_encoding? ? str : str.force_encoding(string.encoding)
   end