Implements more asserts and reading testcases from json files

[halemmerich]

This is mostly a base for discussion in https://forum.espruino.com/conversations/395324/ and extends the runapptests.js by @gfwilliams .

[halemmerich]

I think this is now ok to merge. It is only missing a merged espruino/EspruinoAppLoaderCore#61 and the update of core to pull the change into this repo.

[bobrippling]

Thanks - I've merged #3410 which brings in those app loader core changes. Will leave to @gfwilliams to approve with this being a reasonably central change.

Unrelated / for another time, but I wonder whether we attempt to run the app tests as part of CI, wdyt?

[gfwilliams]

This looks great - thanks for your work on it!

[halemmerich]

Unrelated / for another time, but I wonder whether we attempt to run the app tests as part of CI, wdyt?

I think that would be great. Don't know if we would hit some github limits when we get to a substantial amount of tests, but generally that should be a good idea.

[gfwilliams]

Yes, I think at some point it'd be great to enable these. At least when it's just a few apps it's not going to be a huge amount of extra CPU use.