Fix broken spec for issue 453 and change documentation

Author: Mikel Lindsaar

CHANGELOG.rdoc

@@ -1,5 +1,7 @@
 == HEAD
 
+* Fix failing spec Issue 453 on Ruby 1.9.3
+
 == Version 2.4.4 - Wed Mar 14 22:44:00 +1100 2012 Mikel Lindsaar <mikel@reinteractive.net>
 
 * Fix security vulnerability allowing command line exploit when using file delivery method

lib/mail/version_specific/ruby_1_8.rb

@@ -80,7 +80,10 @@ def Ruby18.q_value_decode(str)
       match = str.match(/\=\?(.+)?\?[Qq]\?(.+)?\?\=/m)
       if match
         encoding = match[1]
-        str = Encodings::QuotedPrintable.decode(match[2].gsub(/_/, '=20'))
+        string = match[2].gsub(/_/, '=20')
+        # Remove trailing = if it exists in a Q encoding
+        string = string.sub(/\=$/, '')
+        str = Encodings::QuotedPrintable.decode(string)
       end
       str
     end

lib/mail/version_specific/ruby_1_9.rb

@@ -68,7 +68,10 @@ def Ruby19.q_value_decode(str)
       match = str.match(/\=\?(.+)?\?[Qq]\?(.+)?\?\=/m)
       if match
         encoding = match[1]
-        str = Encodings::QuotedPrintable.decode(match[2].gsub(/_/, '=20'))
+        string = match[2].gsub(/_/, '=20')
+        # Remove trailing = if it exists in a Q encoding
+        string = string.sub(/\=$/, '')
+        str = Encodings::QuotedPrintable.decode(string)
         str.force_encoding(fix_encoding(encoding))
       end
       decoded = str.encode("utf-8", :invalid => :replace, :replace => "")

spec/mail/encodings_spec.rb

@@ -609,6 +609,12 @@
         b.should eq expected
       end
 
+      it "should unquote Shift_JIS QP with trailing =" do
+        a = "=?Shift_JIS?Q?=93=FA=96{=8C=EA=?="
+        b = Mail::Encodings.unquote_and_convert_to(a, 'utf-8')
+        b.should eq "日本語"
+      end
+
       it "should unquote multiple strings in the middle of the text" do
         a = "=?Shift_JIS?Q?=93=FA=96{=8C=EA=?= <a@example.com>, =?Shift_JIS?Q?=93=FA=96{=8C=EA=?= <b@example.com>"
         b = Mail::Encodings.unquote_and_convert_to(a, 'utf-8')