id	summary	reporter	owner	description	type	status	milestone	component	version	severity	resolution	keywords	cc
12540	Provide customisation point for printing types in tests	Tony Lewis <TonyELewis@…>	Raffi Enficiaud	"AFAIU (from doc ""Logging user defined types""), the current design gives users two options for handling output for their types in tests:
 * Provide `operator<<`
 * Prevent printing with `BOOST_TEST_DONT_PRINT_LOG_VALUE()`

...and all types must be printed.

I suggest that this is to rigid. For some types, users may not want to provide a global `operator<<`, or they may have already provided an `operator<<` or they may not own the type.

For these reasons, I think it would be better if Boost Test provided an explicit customization point that defaulted to calling `operator<<` but that could be overridden by the user to explictly control the Test printing without affecting `operator<<`.

In fact, I think `boost::test_tools::tt_detail::print_log_value` is already close to serving this purpose and perhaps it needs little more than being made part of the public interface and documented.

Thanks for all your work.


PS ""D4381: Suggested Design for Customization Points"" may be relevant here."	Feature Requests	closed	Boost 1.64.0	test	Boost 1.61.0	Optimization	fixed	test,customization,customisation,output,print,stream,insertion operator,print_log_value,BOOST_TEST_DONT_PRINT_LOG_VALUE