Boost 1.55 property_tree INFO parser does not round-trip for \t (tab)

[brewmanz <brewmanz@…>]

Following GTest fails, as embedded tab (\t) has been expanded to a 'real tab' by write_info (note that \n, \0, \r are all escaped properly

	TEST(AdHocTest, AHT0051Boost__property_tree__info_parser_tab)
	{
		std::stringstream ss;
		std::string inputRaw, input, output, exp, act;
		boost::property_tree::ptree ptree;

		inputRaw = "key2 \"value with special characters in it {}; #\\n\\t\\\"\\r\"\n";

		ss.str(inputRaw);
		ASSERT_NO_THROW(boost::property_tree::info_parser::read_info(ss, ptree)) << "parse inputRaw";
		EXPECT_EQ(std::string("value with special characters in it {}; #\n\t\"\r"), ptree.get<std::string>("key2"));

		ss = std::stringstream();
		ASSERT_NO_THROW(boost::property_tree::info_parser::write_info(ss, ptree)) << "extract input";
		input = ss.str();

		exp = "key2 \"value with special characters in it {}; #\\n\\t\\\"\\r\"\n";
		act = input;
		EXPECT_EQ(exp.size(), act.size());
		EXPECT_EQ(exp, act);
		for (size_t ix = 0, diffs = 0; (ix < exp.size()) && (ix < act.size()) && (diffs < 5); ++ix)
		{
			if (exp[ix] != act[ix]) { ++diffs; } 
			EXPECT_EQ(exp[ix], act[ix]) << "ix=" << ix;
		}
	}