unittest::crash_or_die - Execute a code block and exit with exit code 3 if nest does not crash
{ code } [string] crash_or_die -> -
{add_dd} (add_dd) crash_or_die -> success
{add} crash_or_die -> quit
The procedure tests that the code block crashes nest. An example
is a call of operator add_dd in a situation where the operand stack is empty.
add_dd does not check whether the operand stack contains enough data, no exception
is raised. Therefore, the assertion in the C++ implementation of add_dd that the
operand stack contains at least 2 elements fails and nest terminates with the exit
code statusdict::exitcodes::abort. This is the desired behavior and therefore
crash_or_die reports success. There are several alternative and undesired behaviors
of the code block in question. add_dd may raise a StackUnderflow error, return without
raising an error, or crash because of a segmentation fault. This is not the expected behavior
and therefore crash_or_die reports a problem. Like failbutnocrash_or_die, crash_or_die
survives a crash of the code block by probing the code block in a separate nest instance
and inspecting the result. The procedure uses the symbolic exit codes defined in
statusdict::exitcodes, abort is one of them.
This test does not work if nest is compiled with the NDEBUG flag set and it is not
safe to just test for a crash because nest may become inconsistent without crashing.
Therefore, crah_or_die always reports success if the NDEBUG flag is set.
This function will quit nest (exit code 3) if the code does NOT crash nest
with exit code abort. It will print an error message to cerr, too.
SLI-2.0
Diesmann
090209
/var/www/debian/nest/nest-simulator-2.20.0/lib/sli/unittest.sli