1[/ 2 / Copyright (c) 2015 Boost.Test contributors 3 / 4 / Distributed under the Boost Software License, Version 1.0. (See accompanying 5 / file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) 6 /] 7 8[section:boost_test_universal_macro BOOST_TEST: universal and general purpose assertions] 9 10The __UTF__ provides an almost unique interface to a great range of test-case scenarios, through the __BOOST_TEST__ 11macro. The general form of `BOOST_TEST` is the following: 12 13 BOOST_TEST(statement); 14 BOOST_TEST_<level>(statement, optional_modifiers) 15 16An example of use might be the following: 17 18[bt_example boost_test_macro_overview..BOOST_TEST overview..run-fail] 19 20The major features of this tool are: 21 22* a great flexibility for `statement` which may be almost anything: full expression composed by several operations are supported 23 and handled, 24* an extended reporting capability in case of failure: not only `BOOST_TEST` reports the location of the failure and a copy of `statement` itself, 25 but also the values of the operands that permits a rapid identification of the issues related to the failed assertion, 26* the possibility to control better the behavior or the reports of the checks, in particular: 27 28 * floating point comparison: the tolerance may be provided, either using the `BOOST_TEST` 29 directly with `optional_modifiers`, or with /decorators/ (see [link boost_test.testing_tools.extended_comparison.floating_point here] 30 for more details), 31 * container/collection comparisons: different operations for comparison are provided out of the box for comparing collection of 32 elements (default, per-element, lexicographic), with extended diagnostic on failures (covered in 33 [link boost_test.testing_tools.extended_comparison.collections this] section), 34 * string comparison: C-strings operands are automatically detected and the comparisons are performed as if `std::string` objects 35 were used, 36 * optional failure message, 37 * bitwise comparison, providing extended diagnostic in case of failure 38 39[warning To get all the functionalities of `BOOST_TEST` family of assertions, a C++11 capable compiler is required, especially 40 supporting the `auto` and `decltype` keywords and the variadic macros. The documentation focuses on these set of compilers. 41 For compilers not supporting all the features of `BOOST_TEST`, the macro `BOOST_TEST_MACRO_LIMITED_SUPPORT`.] 42 43[#boost_test_statement_overloads][h3 Complex statements] 44`BOOST_TEST` provides an enhanced reporting capability: additional details of the failing operands and operations are provided in the log, 45as shown on the example below: 46 47[bt_example boost_test_macro3..BOOST_TEST enhanced reporting..run-fail] 48 49`BOOST_TEST` parses the `statement` and constructs an expression out of it. `statement` may be a complex expressions 50containing almost any of the overloadable operators in C++: 51 52[table 53 [[Class of operation][operators]] 54 [[binary comparisons][`==`, `!=`, `<`, `>`, `<=`, `>=`]] 55 [[arithmetic compositions][`+`, `-`, `*`, `/`, `%`]] 56 [[bitwise compositions][`|`, `&`, `^`, `<<`, `>>`]] 57 [[assignments][`=`, `+=`, `-=`, `*=`, `/=`, `%=`, `<<=`, `>>=`, `&=`, `^=`, `|=`]] 58] 59 60`statement` is evaluated and cast to `bool`, as if it would appear as argument to an `if` statement: this is the result of the assertion 61 62[h3 Uniform reporting] 63This tool is provided in three variants corresponding to the corresponding 64[link boost_test.testing_tools.tools_assertion_severity_level severity levels]. These three levels of assertions are 65reported into the test log and output, as described in details in the section. The granularity of the 66report depends on the current [link boost_test.utf_reference.rt_param_reference.log_level log level] and 67[link boost_test.utf_reference.rt_param_reference.report_level report level]. 68 69[#boost_test_statement_limitations][h3 Limitations & workaround] 70There are a few constructions that are however unsupported, but adding an extra bracket usually solves that: 71 72* statements containing ternary conditions: those statement should be surrounded by parenthesis as they cannot be overloaded 73* statements containing commas: those statements will be intercepted by the preprocessor 74* compound statements containing any logical composition `||`, `&&`. Those are disabled intentionally and should be surrounded 75 by parenthesis 76 77 BOOST_TEST((true || false)); 78 79 The full details are given in [link boost_test.testing_tools.internal_details this section]. 80 81[bt_example boost_test_macro_workaround..BOOST_TEST limitation and workaround..run] 82 83 84[endsect] [/ boost_test_universal_macro] 85