Is this actually a thing?

# android

[LeoColman]

Is this actually a thing?

[ghedeon]

The OP had a specific requirement to not obfuscate data classes at all. To whitelist them in one batch, like data class is a type or something. Do you have similar restrictions?

[LeoColman]

I don't have any restriction. My app is just crashing when trying to cast a Data Class to itself. Randomly crashes

[Dico]

I think theres an alternative to proguard that works better

[Dico]

Dont quote me on that though

[Dico]

With kotlin*

[kassim]

what does “randomly crashes” mean? is it a new exception each time?
is it in a new line of the code each time?
you should make a Stack Overflow post I think

also, the alternative to Proguard from Google that perhaps Dico was referring to is called R8 (but I don’t have any info to know that its better for Kotlin or not)

[Jay]

I’m new to Android but I’ve used ProGuard before back in the J2ME days circa 2003. It’s a mature well tested project, and as far as I know it operates directly on bytecode. I’d be surprised if it contains fundamental bugs of this sort. However, I don’t know how Kotlin maps things like data classes into Java bytecode so I’m not saying it’s definitely not an issue. I’d write a minimal example to see if it’s reproducible. Doing this might help you realise an issue on your side (or prove that it’s a bug).

[LeoColman]

The random crashes is that the same line of code (a cast of a Sealed class to a Data Class that inherits it) works, unless it's an OnRestoreInstance, in which Proguard screws up and I get a class cast exception (something like a.b.c$a cannot be cast to a.b.c$b. If I add @Keep to the data class, it works

[LeoColman]

IDK if this is a bug in pro guard or if I'm doing something wrong

[kassim]

maybe check the proguard mapping file to see what the classes are
you can also decompile to see the code where it happens

[zokipirlo]

I'm using `data class`es with Proguard and don't see any problems in production.