Add more tests

[cjihrig]

Right now, all of the "tests" are in app.c, which was originally supposed to be an example application using uvwasi. It would be great to split this up into proper tests.

[danbev]

@cjihrig Is there any special testing framework that should be used for this?

[cjihrig]

Good question. I'm not really up to speed on C testing frameworks, so I can't say I have a preference. My primary requests would be something that isn't a maintenance burden and is easy to add and remove tests.

[danbev]

I've used CUnit a little, I could create a PR and see what you think?

[cjihrig]

That would be great! From some quick googling, it doesn't look bad. Do you know if it supports Windows and all/most of the platforms where libuv runs?

[danbev]

Do you know if it supports Windows and all/most of the platforms where libuv runs?

I checked and it looks like Windows support is missing 😞 . I'll search a little more tomorrow and see if what I can find. I think that Check supports Windows so that might be an option.

[cjihrig]

Since we moved to cmake, I added some tests using cmake's built in functionality in #29.

To anyone that might read this: we still need more tests though (which is why I'm leaving this open).