Improve CDATA and comment parse performance

lib/rexml/parsers/baseparser.rb

@@ -449,9 +449,7 @@ def pull_event
               end
               return [ :end_element, last_tag ]
             elsif @source.match?("!", true)
-              md = @source.match(/([^>]*>)/um)
               #STDERR.puts "SOURCE BUFFER = #{source.buffer}, #{source.buffer.size}"
-              raise REXML::ParseException.new("Malformed node", @source) unless md
               if @source.match?("--", true)
                 return [ :comment, process_comment ]
               elsif @source.match?("[CDATA[", true)
@@ -461,9 +459,9 @@ def pull_event
                 else
                   raise REXML::ParseException.new("Malformed CDATA: Missing end ']]>'", @source)
                 end
+              else
+                raise REXML::ParseException.new("Malformed node: Started with '<!' but not a comment nor CDATA", @source)
               end
-              raise REXML::ParseException.new( "Declarations can only occur "+
-                "in the doctype declaration.", @source)
             elsif @source.match?("?", true)
               return process_instruction
             else

test/parse/test_comment.rb

@@ -84,6 +84,19 @@ def test_doctype_malformed_comment_end
         DETAIL
       end
 
+      def test_after_doctype_malformed_node
+        exception = assert_raise(REXML::ParseException) do
+          parse("<a><!a")
+        end
+        assert_equal(<<~DETAIL.chomp, exception.to_s)
+          Malformed node: Started with '<!' but not a comment nor CDATA
+          Line: 1
+          Position: 6
+          Last 80 unconsumed characters:
+          a
+        DETAIL
+      end
+
       def test_after_doctype_unclosed_comment
         exception = assert_raise(REXML::ParseException) do
           parse("<a><!-->")