id,summary,reporter,owner,description,type,status,milestone,component,version,severity,resolution,keywords,cc
10338,Boost.PropertyTree update to v1.56 breaks existing code,Pieter,Sebastian Redl,"Commit 4e7aa973f95b7151282ebcb77dd4cb9316fe920c (""Escape newlines and tabs in content when writing XML."") has broken my code. 
Under certain circumstances, write_xml now produces an XML that starts with:
<?xml version=\""1.0\"" encoding=\""utf-8\""?>\n&#10;<Level_2><Item>0</Item></Level_2>
which cannot be parsed by read_xml (an exception is thrown). Version 1.55 did not have this issue as it did not produce the escape sequence that read_xml chokes on.

Below I have included a unit test that reproduces the problem.



BOOST_AUTO_TEST_CASE(ReadAndWriteWithSpecialCharacters)
{
   using boost::property_tree::ptree;

   // the xml that will be turned into a ptree. Note the linefeed between Level_1 and Level_2 tags
   std::string XmlString = ""<?xml version=\""1.0\"" encoding=\""utf-8\""?><Level_1>\n<Level_2><Item>0</Item></Level_2></Level_1>"";

   std::stringstream StringStream1(XmlString);
   std::stringstream StringStream2;

   // read the xml string
   ptree Level1Tree;
   read_xml(StringStream1,Level1Tree);

   // write the sub-tree at level 1 to string stream 2 as an xml
   ptree Level2Tree = Level1Tree.get_child(""Level_1"");
   write_xml(StringStream2,Level2Tree);

   // show that the xml string has an xml declaration followed by \n&#10; (boost version 1.56)
   // or an xml declaration followed by \n\n (boost version 1.55 and earlier)
   std::string Level2XmlString = StringStream2.str();

   if (BOOST_VERSION >= 105600)
   {
      BOOST_CHECK(Level2XmlString == ""<?xml version=\""1.0\"" encoding=\""utf-8\""?>\n&#10;<Level_2><Item>0</Item></Level_2>"");
   }
   else
   {
      BOOST_CHECK(Level2XmlString == ""<?xml version=\""1.0\"" encoding=\""utf-8\""?>\n\n<Level_2><Item>0</Item></Level_2>"");
   }

   // reading the xml from string stream 2 throws an exception in boost 1.56 but not in boost 1.55
   ptree OutputTree;
   BOOST_CHECK_NO_THROW(read_xml(StringStream2,OutputTree));
}


",Bugs,closed,To Be Determined,property_tree,Boost 1.56.0,Regression,fixed,Escape sequence problem,