belongs_to association should respect association's collection_path

[keegangroth]

fixes #513

[zacharywelch]

We need each association in the list of <HerModel>.associations to include a path. The documentation states this will default to /{class_name}.pluralize/{id} for belongs_to though I agree it should be resource_path or collection_path depending on the type of association.

[keegangroth]

ok I guess that means extracting and generalizing the path building logic from fetch. I'll give it a try when I get a chance

[zacharywelch]

@keegangroth after further thought I'm more inclined to accept a default path of nil on belongs_to 👍 Long term we might want to refactor .associations to resemble something like ActiveRecord::Reflection 😅

Until then, defaulting to nil would have the following, expected behavior on belongs_to associations: use path if provided, otherwise build_request_path would default to resource_path. We'd also need to update the docs for belongs_to (maybe remove the defaults to... language)

@edtjones see any issues here?

[keegangroth]

sounds good, I was not seeing a good way to get at the relevant information where the option defaults were being set. Will have a go at updating the docs.

[zacharywelch]

thanks @keegangroth 🎩 🎉