Re: [Boost-users] Boost.Test BOOST_TEST/BOOST_REQUIRE_MESSAGE message arg problems

Subject: Re: [Boost-users] Boost.Test BOOST_TEST/BOOST_REQUIRE_MESSAGE message arg problems
From: Olaf Peter (ope-devel_at_[hidden])
Date: 2018-08-18 18:38:33

>> OK, my test_observer_fixture with overloads is ready:
>>
>> class test_observer_fixture
>> {
>> Â Â Â Â  struct test_observer : public utf::test_observer
>> Â Â Â Â  {
>> Â Â Â Â  Â Â Â  virtual void test_unit_aborted(utf::test_unit const& tu) 
>> override;
>> Â Â Â Â  Â Â Â  virtual void assertion_result(utf::assertion_result result) 
>> override;
>> Â Â Â Â  Â Â Â  // are the others required for my use case?
>> Â Â Â Â  };
>>
>>      test_observer                                    observer;
>>
>> public:
>> Â Â Â Â  test_observer_fixture();
>> Â Â Â Â  ~test_observer_fixture();
>>
>> public:
>> Â Â Â Â  void setup();
>> Â Â Â Â  void teardown();
>> };
>>
>> and get called by my BOOST_DATA_TEST_CASE. What is the prefered way 
>> to use this Fixture to save the test result in case of failure/abort?
>>
>>
>> BOOST_DATA_TEST_CASE( wave,
>> Â Â Â Â  utf_data::make_delayed<testsuite::dataset_loader>( 
>> "test_case/wave" ),
>> Â Â Â Â  input, expected, orig_file_name)
>> {
>> Â Â Â  ...
>> Â Â Â Â  auto [parse_ok, parse_result] = parse(input, parser, 
>> test_case_name);
>>
>> Â Â Â Â  BOOST_REQUIRE(parse_ok);
>>
>> Â Â Â Â  BOOST_TEST(parse_result == expected, btt::per_element());
>>
>> Â Â Â Â Â Â Â  ??? my_diagnostic_saving .... (orig_file_name, input, 
>> parse_result);
>> Â Â Â Â  );
>> }
>>
>> Thanks,
>> Olaf
>
> Sorry for the late answer,
>
> In the teardown, you may check if the current test had failures. You 
> can do so by accessing the global singleton "results_collector". If 
> "tc" is the current test case (that you can get with 
> "current_test_case"):
>
> test_results const& tr = results_collector.results( tc.p_id );
>
> will give you the result.
>
> If the fixture should be applied to each of the test case inside your 
> suite, you can install it like this:
>
> https://www.boost.org/doc/libs/1_67_0/libs/test/doc/html/boost_test/tests_organization/fixtures/case.html#boost_test.tests_organization.fixtures.case.fixture_for_a_complete_subtree 
>
>
> Accessing via the test result will let you check if this is a failure 
> or an abort: the BOOST_TEST_REQUIRE (BOOST_REQUIRE is deprecated) will 
> fire an abort if I remember well. Using this way to install the 
> fixture will also let you access the instance of the fixture directly 
> (see examples in the documentation).
>
Since my global testobserver works for all events which may interested 
even in the future (e.g exceptions), I have problems to apply them in my 
use case.

I've added a member function to my testobserer fixture

void test_obserer_fixture::failure_diagnostic(std::string const&, ...)Â  
which I can activate on failed tests using the events I've got from 
utf::observer::assertion_result()

Now, in file test_main.cpp I have:
-----------------------------------------
#define BOOST_TEST_MODULE "Test Suite"
#include <boost/test/included/unit_test.hpp>
#include <testsuite/test_observer_fixture.hpp>

using test_observer_fixture = testsuite::test_observer_fixture;
BOOST_TEST_GLOBAL_FIXTURE(test_observer_fixture);
-----------------------------------------

and in (I have several)Â  concrete test case file:
------------------------------------------
#include <boost/test/unit_test.hpp>
#include <boost/test/output_test_stream.hpp>
#include <testsuite/test_observer_fixture.hpp>
...
BOOST_AUTO_TEST_SUITE( my_testsuite )

BOOST_DATA_TEST_CASE( failure_test,...
 Â Â Â  ...,
 Â Â Â  input, expected, test_case_name)
{
...
}
-------------------------------------------

and I can see/log:
# assertion failed: failure_test/test_case/_0

But how to access the global fixture now?

I've changed the test case to:
------------------------------------------
...
BOOST_DATA_TEST_CASE_F(test_observer_fixture, failure_test,
 Â Â Â  ...,
 Â Â Â  input, expected, test_case_name)
{
 Â Â Â  ...
 Â Â Â  failure_diagnostic(...);
}
-------------------------------------------

Boost.Test ships a BOOST_DATA_TEST_CASE_F() macro for this case, which 
is a 'local' fixture, each time constructed and destroyed which is 
expensive - so  I like the idea of a global fixture to save to 
filesystem. Even I've installed it as global one too the events are 
doubled... but I can see that the test observer shows the test status 
followed by the call to failure_diagnostic - so the concept works.

To reduce it: How can I access a member function of global fixture on a 
compilation unit layout shown above.

Thanks,
Olaf