Enhance exception occurred in reducer() w/ state and action

[artem-zinnatullin]

PR enhances error information with current state and action if an error happens inside reducer()'s logic in the user code.

Motivation: it lets the user easily reproduce crashes, reducer() can be just called with this state and action combination that created a crash.

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Tech details:

I went with introducing ReducerException, but I'm not super opinionated on that, if you think that we can use some existing exception type, I'm fine with that. I do however like domain-specific exceptions instead of generic ones.

Also, I had to add : Any constraints on state and action generics because otherwise Kotlin compiler didn't let me assign them to Any fields (which sounds like a compiler bug, right?). And Exceptions are not allowed to be parametrized.

[sockeqwe]

Thanks! Yeah, makes sense to add ReducerException 👍
I'm just not sure exposing state and action could leak private data like user credentials or password. You are the (paranoid 😸 ) security expert, any thoughts?
Adding Any sounds indeed strange but I have the feeling this was done on purpose by the compiler team. I think I saw some discussion around this at YouTrack but I might be wrong or confusing this with something else.

I was wondering if adding generics to ReducerException<S, A> is a good idea. Not sure if people really implement onError() in the subscription (or some other error handlers downstream) but then they should know which type of state and which type of action is used in this Rx Stream, so that they can consume this exception easily by casting I guess.

[artem-zinnatullin]

I'm just not sure exposing state and action could leak private data like user credentials or password. You are the (paranoid 😸 ) security expert, any thoughts?

data classes that contain confidential data should have custom toString() anyway, no matter if they use RxRedux or not! (there are helper projects like https://github.com/hzsweers/redacted-compiler-plugin to do that)

[sockeqwe]

Your are right 👍
Merging this in the afternoon (will set up CI for auto release new versions to maven central from CI before)