Clean and traverse arrays

[nunofgs]

Note: this PR introduces a BC so it will be released in 3.0.0.

Fixes #19.

[callmevlad]

👏 Thank you!

[miskiw]

I am not sure the breaking change was really necessary... but I suppose cleaning objects inside an array is what would be expected from a library with "deep" in the name.

I still think there should be an option to disable this feature (default the option to ON..since the breaking change was introduced) .. just like there are options to disable removing of empty arrays.

either way.. thanks for getting this in. Cheers

[nunofgs]

but I suppose cleaning objects inside an array is what would be expected from a library with "deep" in the name.

That's exactly the reason 😄

I still think there should be an option to disable this feature

We don't have an option to disable nested object cleaning, which is why I believe this is appropriate.

Having said that, this is a small lib so let's see what our users say. If we get requests for adding those two flags I'll gladly add them as a 3.x.x minor bump.

[miskiw]

👍

[Morriz]

Coming after 4 years to say this is problematic, and should be configurable. Imagine this:

react-json-schema-forms creates an undefined value in an array, to render it onscreen to be populated. Now this lib cleans those arrays, even though emptyArrays === false.

How can we disable this lib from cleaning arrays? I deem those as special and should not be touched...

[Morriz]

I suggest this option: cleanArrays = true, that will be used in the logic traversal for arrays like this:

    // Recurse into arrays and objects.
    if ((Array.isArray(value) && cleanArrays) || isPlainObject(value)) {
...

the way it stays backwards compatible