Capture and section state not reported correctly with manual exception handling followed by unhandled exception

[cschreib]

This is a bit of a niche edge case, but following changes in #178 (unreleased, so only affecting the main branch), the following doesn't behave as expected:

For captures:

try {
    int i = 1;
    CAPTURE(i);
    throw std::runtime_error("bad 1");
} catch (...) {
}

throw std::runtime_error("bad 2");

For sections:

try {
    SNITCH_SECTION("section 1") {
        throw std::runtime_error("bad 1");
    }
} catch (...) {
}

throw std::runtime_error("bad 2");

In both cases, the unhandled exception "bad 2" will be reported with the capture/section information of "bad 1".

This will only occur if no snitch macro is encountered between the two throw. So, for example, the following works again as expected:

try {
    int i = 1;
    CAPTURE(i);
    throw std::runtime_error("bad 1");
} catch (...) {
}

// If there is a capture...
int j = 2;
CAPTURE(j);
// ... or a check
CHECK(1 == 2);
// ... or a section
SECTION("subsection 1") { /* ... */ }
// ... then the reported information will be accurate again for unhandled exceptions.

throw std::runtime_error("bad 2");

[cschreib]

Following #183, the problem can now be solved by adding a call to snitch::notify_exception_handled() like so:

try {
    int i = 1;
    CAPTURE(i);
    throw std::runtime_error("bad 1");
} catch (...) {
    snitch::notify_exception_handled();
}

throw std::runtime_error("bad 2");

To clarify, you only need this if all the following conditions are true:

• You are manually catching exceptions in your test code (i.e., you are not using one of the snitch macros for testing exceptions, but rolling your own logic).
• The code executed inside the try block uses snitch macros SECTION(), CAPTURE(), or INFO().
• The code immediately after the try/catch block:
  • can throw, and
  • is not itself inside another explicit try/catch block, and
  • does not use any snitch macro (CHECK_*(), SECTION(), etc.),
• You care that unhandled exceptions in that code are reported with exact contextual information.

This is a fairly niche case, and in most cases omitting the call to snitch::notify_exception_handled() will be fine.