Throw the first seen stream error in writeToStream

[dotboris]

Fixes #30

This makes it so that if the stream we're writing to emit's an error, we interrupt reading the iterator and throw an error.

This makes a somewhat reasonable assumption about stream. It assumes that we're pretty much done with the stream once it emits it's first error.

Technically speaking this is not 100% true when it comes to node since a writable stream can still work and process data even if it has already emitted an error. Also, node streams can emit as many errors as they want.

I think that this is still a reasonable approach. Fail-fast is generally speaking a good idea. On top of what node streams will crash the process on their first unhandled error which is similar behaviour.

[dotboris]

I'm currently testing this with the example I posted in #30 and it doesn't really work as it should.

[reconbot]

ha! beat me to it! What do you think of our two approaches? #34

[dotboris]

@reconbot I like your approach better. I solves some of the problems that I've been hitting when testing with the example script.

[reconbot]

I like your tests better than mine, but I like my approach better because we'll never wait for a drain event after an error has occurred. If you want to interoperate my fix and docs with your tests I'd happily merge.

[dotboris]

@reconbot I'll do exactly that

[dotboris]

@reconbot here you go

• I took your documentation and Promise.race approach
• I kept my tests
• I removed the listener before doing the last error check
• I added an error check at every instance of the loop so that we stop reading the iterator as soon as possible

[reconbot]

👏