attribute: don't convert ' and ' with {attribute_quote: :quote}

GitHub: fix GH-92

Reported by Edouard Brière. Thanks!!!

lib/rexml/attribute.rb

@@ -13,9 +13,6 @@ class Attribute
 
     # The element to which this attribute belongs
     attr_reader :element
-    # The normalized value of this attribute.  That is, the attribute with
-    # entities intact.
-    attr_writer :normalized
     PATTERN = /\s*(#{NAME_STR})\s*=\s*(["'])(.*?)\2/um
 
     NEEDS_A_SECOND_CHECK = /(<|&((#{Entity::NAME});|(#0*((?:\d+)|(?:x[a-fA-F0-9]+)));)?)/um
@@ -141,7 +138,6 @@ def to_s
       return @normalized if @normalized
 
       @normalized = Text::normalize( @unnormalized, doctype )
-      @unnormalized = nil
       @normalized
     end
 
@@ -150,10 +146,16 @@ def to_s
     def value
       return @unnormalized if @unnormalized
       @unnormalized = Text::unnormalize( @normalized, doctype )
-      @normalized = nil
       @unnormalized
     end
 
+    # The normalized value of this attribute.  That is, the attribute with
+    # entities intact.
+    def normalized=(new_normalized)
+      @normalized = new_normalized
+      @unnormalized = nil
+    end
+
     # Returns a copy of this attribute
     def clone
       Attribute.new self

test/test_attributes.rb

@@ -178,18 +178,27 @@ def test_amp_and_lf_attributes
       attr_test('name','value with LF 
 & ampersand')
     end
 
-    def test_quoting
+    def test_quote_root
       d = Document.new(%q{<a x='1' y="2"/>})
       assert_equal( %q{<a x='1' y='2'/>}, d.to_s )
       d.root.context[:attribute_quote] = :quote
       assert_equal( %q{<a x="1" y="2"/>}, d.to_s )
+    end
 
+    def test_quote_sub_element
       d = Document.new(%q{<a x='1' y="2"><b z='3'/></a>})
       assert_equal( %q{<a x='1' y='2'><b z='3'/></a>}, d.to_s )
       d.root.context[:attribute_quote] = :quote
       assert_equal( %q{<a x="1" y="2"><b z="3"/></a>}, d.to_s )
     end
 
+    def test_quote_to_s_value
+      doc = Document.new(%q{<root a="'"/>}, {attribute_quote: :quote})
+      assert_equal(%q{<root a="'"/>}, doc.to_s)
+      assert_equal("'", doc.root.attribute("a").value)
+      assert_equal(%q{<root a="'"/>}, doc.to_s)
+    end
+
     def test_ticket_127
       doc = Document.new
       doc.add_element 'a', { 'v' => 'x & y' }