Add two, admittedly contrived, examples that test
edge cases of the vm module.
They demonstrate that the if statements `if (maybe_rv.IsEmpty())` and
`if (maybe_prop_attr.IsNothing())` in the GetterCallback
and the QueryCallback are observable.
Both GetterCallback and QueryCallback
explicitly check the global_proxy() if a property is
not found on the sandbox. In these tests, the explicit check
inside the callback yields different results than deferring the
check until after the callback. The check is deferred, if the
callbacks do not intercept, i.e., if args.GetReturnValue().Set() is
not called.
PR-URL: https://github.com/nodejs/node/pull/11265
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
