Fix Object.assign example about clean-code-javascript HOT 6 CLOSED

@rkichenama that example does not work because config has already mutated when the 'overrides' are applied:

let config = { key: 'override' }
Object.assign(config, { key: 'default' }, config)
console.log(config.key) // default

Hence the need for an additional Object.assign.

@kwelch that option is equivalent to the non-mutating version I specified - the defaults are already in a new object, so merging them into another new object is redundant.

Anyway, looks like this was fixed in d00ca4c with @kwelch's version.

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Sorry if I'm overthinking it, but I find it rather confusing to provide the example of object mutation in a procedural style, while advising to favor functional programming over imperative programming.

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If the purpose is to mutate config to add defaults but keep changes, then the example should be

function createMenu(config) {
  Object.assign(
    config, // object to merge changes into
    {
      title: 'Foo',
      body: 'Bar',
      buttonText: 'Baz',
      cancellable: true
    }, // defaults
    config // overrides
);
}

createMenu({ title: 'Not Foo' });

IMHO, I think this is the case since there is no return and we are dealing with objects, passed by reference.

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I would say the best option would be to maintain the passed in parameter and create a new object all together that use defaults then user param.

function createMenu(options) {
  let config = Object.assign({}, {
      title: 'Foo',
      body: 'Bar',
      buttonText: 'Baz',
      cancellable: true
    }, // defaults
    options // overrides
  );
}

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@connec I agree ours are the same, I just prefer not editing parameters if you are attempting to be functional.

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