Is it 100% correct to replace !!someVar with Boolean(someVar)?

Question

I am refactoring a bunch of old code and see that JSCS shows a warning about implicit type conversion for !!someVar statements.

Is it correct to replace all these im

Answer 1

Is it 100% correct to replace !!someVar with Boolean(someVar)?

No. The global Boolean variable might be overwritten/shadowed, the !! operators cannot.

Is it correct to replace all these implicit conversions with Boolean(someVar) so that nothing breaks due to this change?

Yes. If your code breaks because of this change, it should be considered already broken, and you should fix the thing that messes with Boolean instead.