tree 4b95d9e701d1e6db55406550754a2b7cc6bbd7ce
parent 28f174fd8310937426d2f16135cb646aadc14997
author Ilya Yanok <yanok@google.com> 1684484695 -0700
committer Copybara-Service <copybara-worker@google.com> 1684484721 -0700

Extend using run-time dummy values to Futures

If we have to create a `Future` of an unknown type, we have two
alternatives:

 1. Create a fake class implementing `Future`. This is guaranteed
    to fail if ever `await`ed, but works nice when setting
    expectations.
 2. Try to find a value for `T` at run-time and create a real
    future. That can always fail if there is no dummy for `T`.

This change tries to unite these approaches:
 - It adds `dummyValueOrNull` function that returns `null` instead
   of throwing.
 - If we need a value of type `Future<T>`, first try if we have a
   dummy value for `T`. If it works, go with the real future,
   otherwise fall back to faking.

PiperOrigin-RevId: 533386034