Document and test the recursion limit

[GrosSacASac]

deepCopy and others are recursive functions, in theory the maximum call stack can be reached if the object is very deep.

Add a warning in the comments. Make manual tests to find out the limits on various engines.

[GrosSacASac]

I am not interested in implementing a user land iterative approach for performance or complexity reasons

[Raene]

Can i get an example of what is expected. e.g the object it'll take since different objects depth would give different outputs.
So how deep are we going?

[GrosSacASac]

Object of depth 1

{a:1}

Object of depth 4

{{{{a:1}}}}

The goal is to find when the depth increases too much it could crash depending on the JS engine

[GrosSacASac]

So you have to generate different inputs programmatically and call deepCopy and see if it crashes