Hey there! I use this tool to manage the state of my application in local storage. Recently I have been receiving issues about weird behaviours in my app, and I couldn't really detect the reason for them, until someone was able to give me a step-by-step guide on how to reproduce it, with a sample data. In my app, the user can provide JSON data in a text editor interface, which I store in local storage as a string. Whenever the app is restarted, the JSON string is serialized to null. After digging through the code to check if I am indeed resetting the value to null, I realized the null value was actually an Invalid Date object.

Here's a sample string:

{
  "BIRTHDAY": "1999-12-01T06:23:22.886Z"
}

It turns out, that the dateReviver simply tests for a match in the provided string with a date regex and if found, it instantiates the entire string as a Date object. As you can see from the example string above, while there is indeed a date sub string matching a date regex, the string itself is not a date and so reviving it as a date is a wrong assumption. At the least, the regex should check that only the date string is found and it isn't part of a larger string. Setting restoreDates to false fixed the issue for me.

Also, I don't think enabling the dateReviver should be the default case for this. It seems to only be useful in specific cases. It's already known that once an object is serialized to JSON (to be stored), it loses all its dynamic properties, and so one would expect the date to be a string, and only if required, should the restoreDates be true.