Broken with Hashie >= 3.0.0

[KOBA789]

Hashie >= 3.0.0 Mash::respond_to? always returns true when given method name ending with "!", "?", "_", "=".
Ref: hashie/hashie@5ac8516#diff-167a475bc5a73269819928a9da362073R190

It breaks this garage's code:
https://github.com/cookpad/garage/blob/master/lib/garage/representer.rb#L159

Garage assumes instance of Hashie::Mash to be a instance including Garage::Representer.
As a result of it, it fails at here with a message "NoMethodError: undefined method `params' for Hashie::Mash:Class ".

I suggest specifying Hashie < 3.0.0 in gemspec.

[taiki45]

I think specifying Hashie < 3.0.0 has bad side, that garage gem restricts users to use Hashie 3.0.0 above.

The one of alternatives is not checking the value responds to represent! but checking the value includes Garage::Representer. Because the value must respond to params= and partial= and more, checking againt represent! is not enought.

I think alternative plan is reasonable. How do you think?

[luvtechno]

We are facing this issue in our garage app, where hashie 3.4.3 is used.

The one of alternatives is not checking the value responds to represent! but checking the value includes Garage::Representer. Because the value must respond to params= and partial= and more, checking againt represent! is not enought.

This sounds good to me -- we are monkey patching as such and going to test with our app.

cc/ @creasty