Boost C++ Libraries

...one of the most highly regarded and expertly designed C++ library projects in the world. — Herb Sutter and Andrei Alexandrescu, C++ Coding Standards

This is the documentation for an old version of Boost. Click here to view this page for the latest version.

`BOOST_<level>_THROW`

BOOST_WARN_THROW(expression, exception_type);
BOOST_CHECK_THROW(expression, exception_type);
BOOST_REQUIRE_THROW(expression, exception_type);

These assertions validate that the execution of expression raises an expected exception, which means an exception of the supplied exception_type type or of any child type.

If expression raises an unexpected exception, this exception is not caught by BOOST_<level>_THROW assertion and might propagate to the test body. If not caught at all, the framework will catch it and terminate the test case with the status failed.
If expression does not raise any exception, the the assertion fails.

	Warning
	the assertion catches only the expected exceptions.

	Tip
	It is possible to test for complex expressions with the use of constructs such as `do { /* ... */} while(0)` block.

Example: BOOST_<level>_THROW usage

Code
#define BOOST_TEST_MODULE example #include <boost/test/included/unit_test.hpp> class my_exception{}; BOOST_AUTO_TEST_CASE( test ) { int i = 0; BOOST_CHECK_THROW( i++, my_exception ); }

Output
> example Running 1 test case... test.cpp(11): error in "test": exception my_exception is expected *** 1 failures is detected in test suite "example"

See also:

BOOST_<level>_NO_THROW
Exception correctness section