[boost] [test] Broken header (via indirect #includes)

From: Daryle Walker (darylew_at_[hidden])
Date: 2008-07-13 16:50:17

I was fixing up a test file, and the compilation failed complaining  
that "'type' is not a member of 'boost'" within the innards of a  
"BOOST_AUTO_TEST_CASE_TEMPLATE" line.  I figured out that the error  
was referring to the obscure boost::type class template in "boost/ 
type.hpp".  I included that file, and then the compiler complained  
saying that "'template_test_case_gen' is not a member of  
'boost::unit_test::ut_detail'."  Doing a multiple-file search, I  
realized the true problem.

1. BOOST_AUTO_TEST_CASE_TEMPLATE is #defined in "boost/test/ 
unit_test_suite.hpp"
2. This template depends on boost::type and  
boost::unit_test::ut_detail::template_test_case_gen
3. template_test_case_gen is defined in "boost/test/ 
test_case_template.hpp", which happens to #include "boost/type.hpp"
4. Neither of the appropriate headers are directly #included in  
"unit_test_suite.hpp"
5. I guess that one or both headers were indirectly #included in  
"unit_test_suite.hpp", but that indirect header purged the headers I  
needed, and the author _forgot_ that another header was counting on  
the old indirect #include.

I worked around the problem for now by directly #including "boost/ 
test/test_case_template.hpp" in my test file.

But I shouldn't have to do this.

Worse, this has happened before with Boost.Test, in regards to the  
floating point comparison tests.  Those test macros called a function  
that wasn't in the same header, nor #included; i.e. the user has to  
add an extra #include for the floating-point test macros to work.   
The floating-point incident was a deliberate design decision, but I  
guess that my problem here was caused by accident.

The point: DIRECTLY #include everything a macro needs in that macro's  
header.  I'm sick & tired of hunting all the extra headers I need.   
Worse, I'll have to re-hunt when my test program craps out if/when  
the author re-arranges all the macros & headers.

My point [5] is only a guess because I wasted two hours searching the  
trac/subversion site for where & when the author broke the build.  I  
didn't find it, and I figured that I shouldn't have to.

When you fix this, let me know so I can remove the extra #include  
from my test file.

(Apologies in advance if the real problem is that my subversion  
working copy is severely fried.)

-- 
Daryle Walker
Mac, Internet, and Video Game Junkie
darylew AT hotmail DOT com