* lib/rexml/encoding.rb (REXML::Encoding#encoding=): store @encoding

  a String which means the name of the encoding.
  this partially revert r29646.

* lib/rexml/document.rb: follow above.

* lib/rexml/output.rb: ditto.

* lib/rexml/parsers/baseparser.rb: ditto.

* lib/rexml/source.rb: ditto.

* lib/rexml/xmldecl.rb: ditto.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@31008 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

7 files changed, 26 insertions, 43 deletions

diff --git a/lib/rexml/document.rb b/lib/rexml/document.rb
index 68a744d9e5..790a1c78db 100644
--- a/lib/rexml/document.rb
+++ b/lib/rexml/document.rb
@@ -184,7 +184,7 @@ module REXML
     #   that IE's limited abilities can handle.  This hack inserts a space
     #   before the /> on empty tags.  Defaults to false
     def write( output=$stdout, indent=-1, transitive=false, ie_hack=false )
-      if xml_decl.encoding != ::Encoding::UTF_8 && !output.kind_of?(Output)
+      if xml_decl.encoding != 'UTF-8' && !output.kind_of?(Output)
         output = Output.new( output, xml_decl.encoding )
       end
       formatter = if indent > -1
diff --git a/lib/rexml/encoding.rb b/lib/rexml/encoding.rb
index 3e7bdfb6aa..d1d5172841 100644
--- a/lib/rexml/encoding.rb
+++ b/lib/rexml/encoding.rb
@@ -1,8 +1,9 @@
 module REXML
   module Encoding
-    # ID ---> Encoding object
+    # ID ---> Encoding name
     attr_reader :encoding
     def encoding=(encoding)
+      encoding = encoding.name if encoding.is_a?(Encoding)
       if encoding.is_a?(String)
         original_encoding = encoding
         encoding = find_encoding(encoding)
@@ -11,35 +12,25 @@ module REXML
         end
       end
       return false if defined?(@encoding) and encoding == @encoding
-      if encoding and encoding != ::Encoding::UTF_8
-        @encoding = encoding
+      if encoding
+        @encoding = encoding.upcase
       else
-        @encoding = ::Encoding::UTF_8
+        @encoding = 'UTF-8'
       end
       true
     end
 
     def check_encoding(xml)
-      # We have to recognize UTF-16, LSB UTF-16, and UTF-8
+      # We have to recognize UTF-16BE, UTF-16LE, and UTF-8
       if xml[0, 2] == "\xfe\xff"
         xml[0, 2] = ""
-        ::Encoding::UTF_16BE
+        return 'UTF-16BE'
       elsif xml[0, 2] == "\xff\xfe"
         xml[0, 2] = ""
-        ::Encoding::UTF_16LE
-      else
-        if /\A\s*<\?xml\s+version\s*=\s*(['"]).*?\1
-            \s+encoding\s*=\s*(["'])(.*?)\2/mx =~ xml
-          encoding_name = $3
-          if /\Autf-16\z/i =~ encoding_name
-            ::Encoding::UTF_16BE
-          else
-            find_encoding(encoding_name)
-          end
-        else
-          ::Encoding::UTF_8
-        end
+        return 'UTF-16LE'
       end
+      xml =~ /^\s*<\?xml\s+version\s*=\s*(['"]).*?\1\s+encoding\s*=\s*(["'])(.*?)\2/m
+      return $3 ? $3.upcase : 'UTF-8'
     end
 
     def encode(string)
@@ -53,14 +44,19 @@ module REXML
     private
     def find_encoding(name)
       case name
-      when "UTF-16"
-        name = "UTF-16BE"
       when /\Ashift-jis\z/i
-        name = "Shift_JIS"
+        return "SHIFT_JIS"
       when /\ACP-(\d+)\z/
         name = "CP#{$1}"
+      when /\AUTF-8\z/i
+        return name
+      end
+      begin
+        ::Encoding::Converter.search_convpath(name, 'UTF-8')
+      rescue ::Encoding::ConverterNotFoundError
+        return nil
       end
-      ::Encoding.find(name)
+      name
     end
   end
 end
diff --git a/lib/rexml/formatters/default.rb b/lib/rexml/formatters/default.rb
index ec4149047d..574c821f96 100644
--- a/lib/rexml/formatters/default.rb
+++ b/lib/rexml/formatters/default.rb
@@ -22,7 +22,7 @@ module REXML
         case node
 
         when Document
-          if node.xml_decl.encoding != ::Encoding::UTF_8 && !output.kind_of?(Output)
+          if node.xml_decl.encoding != 'UTF-8' && !output.kind_of?(Output)
             output = Output.new( output, node.xml_decl.encoding )
           end
           write_document( node, output )
diff --git a/lib/rexml/output.rb b/lib/rexml/output.rb
index 752f6e1d40..50333ba177 100644
--- a/lib/rexml/output.rb
+++ b/lib/rexml/output.rb
@@ -10,7 +10,7 @@ module REXML
       @output = real_IO
       self.encoding = encd
 
-      @to_utf = (@encoding != ::Encoding::UTF_8)
+      @to_utf = encd != 'UTF-8'
     end
 
     def <<( content )
diff --git a/lib/rexml/parsers/baseparser.rb b/lib/rexml/parsers/baseparser.rb
index ee8b160ce5..0f1480b07d 100644
--- a/lib/rexml/parsers/baseparser.rb
+++ b/lib/rexml/parsers/baseparser.rb
@@ -248,7 +248,7 @@ module REXML
             @document_status = :after_doctype
             @source.read if @source.buffer.size<2
             md = @source.match(/\s*/um, true)
-            if @source.encoding == ::Encoding::UTF_8
+            if @source.encoding == "UTF-8"
               @source.buffer.force_encoding(::Encoding::UTF_8)
             end
           end
diff --git a/lib/rexml/source.rb b/lib/rexml/source.rb
index 227b0c56c4..112393cfd4 100644
--- a/lib/rexml/source.rb
+++ b/lib/rexml/source.rb
@@ -54,14 +54,12 @@ module REXML
     def encoding=(enc)
       return unless super
       @line_break = encode( '>' )
-      if @encoding != ::Encoding::UTF_8
+      if @encoding != 'UTF-8'
         @buffer = decode(@buffer)
         @to_utf = true
       else
         @to_utf = false
-        if @buffer.respond_to? :force_encoding
-          @buffer.force_encoding ::Encoding::UTF_8
-        end
+        @buffer.force_encoding ::Encoding::UTF_8
       end
     end
 
diff --git a/lib/rexml/xmldecl.rb b/lib/rexml/xmldecl.rb
index 81d3057732..361e4b7106 100644
--- a/lib/rexml/xmldecl.rb
+++ b/lib/rexml/xmldecl.rb
@@ -109,20 +109,9 @@ module REXML
     end
 
     private
-    def normalized_encoding_name(_encoding)
-      if _encoding == ::Encoding::UTF_16BE
-        "UTF-16"
-      else
-        return _encoding.name
-      end
-    end
-
     def content(enc)
       rv = "version='#@version'"
-      if @writeencoding || enc.to_s !~ /\Autf-8\z/i
-        encoding_name = normalized_encoding_name(enc)
-        rv << " encoding='#{encoding_name}'"
-      end
+      rv << " encoding='#{enc}'" if @writeencoding || enc !~ /utf-8/i
       rv << " standalone='#@standalone'" if @standalone
       rv
     end