Add tests to cover more complex scenarios and cross-platform cases.

[ithinkicancode]

Motivation

Currently the test cases are pretty simple. More complex scenarios should be covered. Additionally tests for other platforms (namely JS and native) should also be added to make sure behaviors on those platforms are within our expectation.

[adamgfraser]

In general we shouldn't be adding platform specific tests. We should be presenting a consistent cross platform interface and our tests should pass on all platforms. Definitely agree about more tests being great though!

[ithinkicancode]

I agree. Platform-specific tests should be avoided. That thought stemmed from that scenario I had with JS test case and our convos on Discord. But I agree that should be avoided. And at the moment, I don't think we need platform-specific tests.