This is because there's no proper way to catch panics in Rust, which
makes it hard to know _which_ test did cause the panic when this
happen. The stack trace gives little detail about this, but we can
print this information before it happens -- making it easier to
identify the culprit.
Pretty useful for debbugging. Though, on second-thoughts, this is
something we may want to review later and maybe have that done by
default for tests.
At the moment, we expects tests to unify to `bool`, and treat `false`
values as failing tests. Yet, on failures, this gives little
information about what's wrong with the test.
It'd be nice to either have better way to assert in tests, or, to
simply accept non-bool tests, and show whatever the test evaluates
to as a debug output.
KtorZ