Boost C++ Libraries

"Decorator" is a uniform mechanism for updating various attributes of the automatically registered test units. These attributes affect how the test tree is processed during the execution of the test module and include test unit description, floating-point tolerance and the number of expected failures among others. They are listed in detail in the following sections.

Test case decorators

You can apply more than one decorator to the same test unit. A list of decorators is applied to a test case by specifying it as the second argument to macro BOOST_AUTO_TEST_CASE or the third argument to macro BOOST_FIXTURE_TEST_CASE.

Example: Test unit decorators

#define BOOST_TEST_MODULE decorator_01
#include <boost/test/included/unit_test.hpp>
namespace utf = boost::unit_test;

BOOST_AUTO_TEST_CASE(test_case1, * utf::label("trivial"))
{
  BOOST_TEST(true);
}

BOOST_AUTO_TEST_CASE(test_case2,
  * utf::label("trivial")
  * utf::label("cmp")
  * utf::description("testing equality of ones"))
{
  BOOST_TEST(1 == 1);
}

> decorator_01 --run_test=@trivial
Running 2 test cases...

*** No errors detected


> decorator_01 --run_test=@cmp
Running 1 test case...

*** No errors detected

Each decorator in the list is preceded by an asterisk (*); the subsequent syntax resembles a function call and is specified in detail for each decorator. If there is more than one decorator in the list, they are concatenated with no additional separator; each asterisk indicates the beginning of a decorator. In the above example, test case test_case1 has one associated decorator: label. This means that when test units are filtered based on label, this test case will match to label "trivial". Test case test_case2 has three associated decorators: two of type label and one of type description.