How do I correctly use C/C++
assert()in my tests?
While the assert() macro provided by the C/C++ <assert.h>/<cassert>
headers is pretty basic compared to the modern testing frameworks, it is often
adequate for simple tests and does not require any extra
dependencies.
However, using assert() correctly in tests requires some care. Specifically,
we need to make sure that the NDEBUG macro (which, if defined, disables the
assertion functionality) is not defined for our tests. The recommended way to
achieve this is to include <assert.h>/<cassert> last and undefine NDEBUG
just before that. For example:
#include <string>
#undef NDEBUG
#include <cassert>
int main ()
{
assert (std::string ("test") == "test");
}
Note that the "include <assert.h>/<cassert> last" part is important
since we still want NDEBUG to have its normal effect in other headers
that we include.