Do not log symbols using util.inspect

Question

I have this object which has some symbols properties on it:

{
  foo: 'bar',
  [Symbol(raw.json.bytes)]: 13,
  [Symbol(raw.json.str)]: '{"foo":"bar"}'
} 

now, I added those symbol properties myself, so maybe I can change how I add them using Object.defineProperty. Is there some way to prevent logging the symbols either:

1. using an option to util.inspect(v, opts)
2. Or by using Object.defineProperty?

Either way I am using util.inspect() to stringify the object, and my preference is to pass it an option to not log non-enumerable properties or what not.

Answer 1

You can do it if the showHidden option is set to false (default) by using non-enumerable symbols.

To do this, define symbols the following way:

Object.defineProperty(obj, symbol, {
  enumerable: false,  //that matters!
  configurable: true, //or false
  writable: true,     //or false
  value: value
})

Properties defined like this (not necessarily symbols¹) will not be included in util.inspect calls if the showHidden option is false.

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^{1: Defining non-enumerable non-symbol properties has the side effect of skipping them when iterating over the keys/values of an object with for..in loops, Object.keys() or Object.values(). Read more on MDN or in this SO post}