State is not treated as immutable

[pennersr]

The example setter and the current implementation mutate state in the versionSetter code:

(state, version) => state.app.version = version

and:

state[versionString] = state[versionString] || {};
state[versionString].version = version;

[jgkim]

Because redux and redux-persist themselves are not immutability aware, the default seems to be OK to me. If you use the immutable state, then you can use a custom version setter. I guess redux-persist-migrate do the job before transforms of redux-persist so that you can use a setter that handles the transformed and saved state.

[rt2zz]

ya that was my thinking. Immutability would be nice, but in this case it would complicate things. I am open to ideas however for how it can be simply and performantly implemented.

[ndbroadbent]

It might be nice to support Immutabile.JS and seamless-immutable out of the box. I don't think performance really matters since it's just run one time when the app is started. Checking for these libraries would only add a couple of lines of code.

[ndbroadbent]

Actually I think this should be implemented as a transform. That would make a lot more sense. Then you could just run it before the immutability transform.