[Boost-bugs] [Boost C++ Libraries] #10338: Boost.PropertyTree update to v1.56 breaks existing code

Subject: [Boost-bugs] [Boost C++ Libraries] #10338: Boost.PropertyTree update to v1.56 breaks existing code
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2014-08-10 17:52:20

#10338: Boost.PropertyTree update to v1.56 breaks existing code
-------------------------------------+---------------------------
 Reporter:  Pieter                   |      Owner:  cornedbee
     Type:  Bugs                     |     Status:  new
Milestone:  To Be Determined         |  Component:  property_tree
  Version:  Boost 1.56.0             |   Severity:  Regression
 Keywords:  Escape sequence problem  |
-------------------------------------+---------------------------
 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));
 }

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/10338>
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