test/doc/test_organization/test_suites.qbk

[/
 / Copyright (c) 2003 Boost.Test contributors
 /
 / Distributed under the Boost Software License, Version 1.0. (See accompanying
 / file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
 /]

[section:test_suite Test suite]
If you consider test cases as leaves on the test tree, the test suite can be considered as branch and the /master
test suite/ as the /root/. Unlike real trees though, our tree in many cases consists only of leaves attached
directly to the root. This is common for all test cases to reside directly in the master test suite. If you do
want to construct a hierarchical test suite structure the __UTF__ provides both manual and automated
test suite creation and registration facilities:

# Test suite with automated registration
# Manually registered test suite

In addition the __UTF__ presents a notion of the
[link boost_test.tests_organization.test_tree.master_test_suite Master test suite].
The most important reason to learn about this component is that it provides an ability to access
command line arguments supplied to a test module.

[#ref_BOOST_AUTO_TEST_SUITE][h3 Automated registration]
The solution the __UTF__ presents for automated test suite creation and registration is designed to facilitate
multiple points of definition, arbitrary test suites depth and smooth integration with automated test case creation
and registration. This facility should significantly simplify a test tree construction process in comparison with
manual explicit registration case.


The implementation is based on the order of file scope variables definitions within a single compilation unit.
The semantic of this facility is very similar to the namespace feature of C++, including support for test suite
extension. To start test suite use the macro __BOOST_AUTO_TEST_SUITE__. To end test suite use the macro
__BOOST_AUTO_TEST_SUITE_END__. The same test suite can be restarted multiple times inside the same test file or in a
different test files. In a result all test units will be part of the same test suite in a constructed test tree.

``
  BOOST_AUTO_TEST_SUITE(test_suite_name);
  BOOST_AUTO_TEST_SUITE_END();
``

Test units defined in between test suite start and end declarations become members of the test suite. A test
unit always becomes the member of the closest test suite declared. Test units declared at a test file scope
become members of the master test suite. There is no limit on depth of test suite inclusion.


This example creates a test tree that matches exactly the one created in the manual test suite registration
example.

[bt_example example12..Test suites with automated registration..run-fail]

As you can see test tree construction in this example is more straightforward and automated.

In the example below, the test suite `test_suite` consists of two parts. Their definition is remote and is separated by another
test case. In fact these parts may even reside in different test files. The resulting test tree remains the same. As
you can see from the output both `test_case1` and `test_case2` reside in the same test suite `test_suite`.

[bt_example example53..Test suite extension using automated registration facility..run-fail]

[h3 Test suites with manual registration]
To create a test suite manually you need to

# create an instance of [classref boost::unit_test::test_suite] class,
# register it in test tree, and
# populate it with test cases (or lower level test suites).

[#ref_test_case_registration][h4 Test unit registration interface]


The __UTF__ models the notion of test case container - test suite - using class [classref boost::unit_test::test_suite]. For
complete class interface reference check advanced section of this documentation. Here you should only be
interested in a single test unit registration interface:

``
  void test_suite::add( test_unit* tc, counter_t expected_failures = 0, int timeout = 0 );
``

The first parameter is a pointer to a newly created test unit. The second optional parameter -
expected_failures  - defines the number of test assertions that are expected to fail within the test unit. By
default no errors are expected.

[caution
  Be careful when supplying a number of expected failures for test suites. By default the __UTF__ calculates the
  number of expected failures in test suite as the sum of appropriate values in all test units that constitute
  it. And it rarely makes sense to change this.
]

The third optional parameter - `timeout` - defines the timeout value for the test unit. As of now the __UTF__
isn't able to set a timeout for the test suite execution, so this parameter makes sense only for test case
registration. By default no timeout is set. See the method
[memberref boost::unit_test::test_suite::add] for more details about the timeout value.

To register group of test units in one function call, the [classref boost::unit_test::test_suite `test_suite`] class provides another
[memberref boost::unit_test::test_suite::add `add`] interface covered in the advanced section of this documentation.


[#ref_BOOST_TEST_SUITE][h4 Test suite instance construction]


To create a test suite instance manually, employ the macro __BOOST_TEST_SUITE__. It hides all implementation
details and you only required to specify the test suite name:

``
  BOOST_TEST_SUITE(test_suite_name);
``

__BOOST_TEST_SUITE__ creates an instance of the class `boost::unit_test::test_suite` and returns a pointer to the
constructed instance. Alternatively you can create an instance of class `boost::unit_test::test_suite` yourself.

[caution `boost::unit_test::test_suite` instances have to be allocated on the heap and the compiler won't allow you
      to create one on the stack.
]

Newly created test suite has to be registered in a parent one using the `add` interface. Both test suite creation and
registration is performed in the test module initialization function.

The example below creates a test tree, which can be represented by the following hierarchy:

[$images/class-hier.jpg]

[bt_example example11..Manually registered test suites..run]

[endsect] [/ test suite]

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