Test for the new exception of delegate_missing_to

[colorfulfool]

A follow-up to the change to delegate_missing_to made in #30084.

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[rafaelfranca]

Based on @matthewd's comment in the original PR, can you change the implementation to only check for nil if super raises NoMethodError?

[colorfulfool]

Done. I didn't go this way initially because the code turns out not pretty. Is there a better way to write it?

[rafaelfranca]

You can remove the begin here.

[rafaelfranca]

This method should be private, and starts with _ to avoid conflicts with the methods in the including class.

[gsamokovarov]

Should we extract the method at all, we're still monkey patching a core object here. Any pollution counts.

[rafaelfranca]

Yeah, I don't think it is necessary. begin/end inside that else is good enough.

[rafaelfranca]

I think that is fine

[colorfulfool]

Is delegate_missing_to meant to be used multiple times on the same class? If not, I can eliminate most of _delegation_error_if_target_nil arguments.

I'd say it isn't, because you can instead do

delegate_missing_to :person_responsible

def person_responsible
  president || chief || captain
end

[rafaelfranca]

It is not, because only the last call is going to be used.

[rafaelfranca]

I think we can go with the version without the private method just to avoid polluting the caller more

[rafaelfranca]

This is amazing. Thank you for doing this.