Remove ParametersMatcher from Invocation#call_description

[wasabigeek]

This is a somewhat odd usage of ParametersMatcher, and I think unnecessarily couples it to Invocation#call_description.

I've chosen to duplicate the mocha_inspect logic for now because it seemed possible for them to work differently e.g. Invocation should never contain matchers (right?).

Does this look fine to you @floehopper?

[floehopper]

This is a somewhat odd usage of ParametersMatcher, and I think unnecessarily couples it to Invocation#call_description.

I've chosen to duplicate the mocha_inspect logic for now because it seemed possible for them to work differently e.g. Invocation should never contain matchers (right?).

Does this look fine to you @floehopper?

@wasabigeek

I feel slightly uncomfortable with the amount of duplicated code, but if this is going to make it easier to refactor the parameter matching code then I can probably live with it. It would help me to know if there's something specific that this change unlocks?

[wasabigeek]

It mainly allows Invocation and ParametersMatcher to have different APIs - currently ParametersMatcher#initialize needs an array of args or Matchers, which Invocation#arguments can fit into. But I'm hoping that Invocation can have separate #positional_arguments and #keyword_arguments (see #544), and don't want to expose a public #arguments method just to fit into ParametersMatcher's API.

We might even be able to build the descriptions completely from #positional_arguments and #keyword_arguments, which would change the logic here and make it no longer duplicated 👍

[wasabigeek]

I think it's also worth mentioning that duplication notwithstanding, this removes a fair amount of indirection:

• Invocation#arguments passes an Array of objects into ParametersMatcher#initialize
• ParametersMatcher#mocha_inspect will first convert that Array into an Array of ParameterMatchers::Equals with the original object as the underlying value (my assumption here is that Invocation#arguments would not include any matchers instances, so all elements would be converted to ParameterMatchers::Equals.)
• Array#mocha_inspect will then call ParameterMatchers::Equals#mocha_inspect, which then calls mocha_inspect on the underlying value

This change would call mocha_inspect on the original objects immediately instead.

[floehopper]

@wasabigeek A couple of quick things:

1. I've just belatedly enabled PR builds on CircleCI - I only recently realised we lost this capability when we moved from TravisCI and only even more recently realised I could enable it in the CircleCI settings - so I apologise for having made you setup CircleCI on your own fork. Please feel free to open new PRs if that would make things simpler to explain.

2. @nitishr has just submtted Use Ruby v1.9 features #547 which (amongst other things) uses Rubocop auto-correct to move to the default Style/HashSyntax style which is ruby19, i.e. "forces use of the 1.9 syntax when hashes have all symbols for keys". I thought the pervasive nature of this change might cause you issues and so I've proposed holding off on it for now.

[floehopper]

@wasabigeek Thanks for explaining your motivations so clearly. That all makes sense to me. I'll get this merged shortly.