Re: [Boost-users] [test] Unexpected Exceptions

Subject: Re: [Boost-users] [test] Unexpected Exceptions
From: Florian Winter (fw_at_[hidden])
Date: 2009-11-23 03:44:28

Hi,

Gennadiy Rozental wrote:
> Florian Winter <fw <at> motama.com> writes:
>
>   
>> Hi,
>>
>> What is the intended behavior of Boost.Test if an unexpected exception
>> is thrown? Example:
>>
>>   void do_not_throw() throw() {
>>     throw "unexpected";
>>   }
>>
>> Some of my applications using Boost.Test seem exit with an error code of
>> 0 (successful) if an unexpected exception is thrown. Is this the
>> intended behavior?
>>     
>
> What compiler are you using?
>   
The problem has been observed with GCC 4.3.1. I am using Boost version
1.35.0, which is pretty old...

Also, my actual test case is more complex. It involves shared libraries
and Boost.Test being built in a custom way, so you shouldn't expect to
be able to reproduce the problem using only the code snippet I provided
above.

(I am also aware that the code snippet does not make any sense. In a
"real" unit test, the exception is thrown deeper in the stack hierarchy
below either a throw() function or the main function of a thread. This
is of course a bug in my software, and I would like to detect this bug
by a unit test, which requires that the unit test fails in case of an
unexpected exception)

Before I provide more information, I would like to know what Boost.Test
is _expected_ to do in the case of unexpected exceptions, so I know if
I'm actually seeing a bug or expected behavior. In my test cases, I see
output similar to the following when an unexpected exception is thrown:

-----
Running 1 test case...
terminate called after throwing an instance of 'const char*'

*** No errors detected
-----

and the process exits with a result value of 0. This looks like
Boost.Test is "catching" the error (probably using set_unexpected),
because otherwise, the process would not exit with a result value of 0.
> It seems that MSVC for example does not follow standard here:
> http://msdn.microsoft.com/en-us/library/7twc8dwy(VS.80).aspx
>   
How? What is the problem with MSVC and set_unexpected, and what are the
consequences for the behavior of Boost.Test?

Regards,
Florian