Add support for custom default controller configuration

[codebycliff]

Description

This pull request adds configuration to draper so that you can customize the default controller. According to the documentation in the README:

Configuration

Draper works out the box well, but also provides a hook for you to configure its
default functionality. For example, Draper assumes you have a base ApplicationController.
If your base controller is named something different (e.g. BaseController),
you can tell Draper to use it by adding the following to an initializer:

Draper.configure do |config|
 config.default_controller = BaseController
end

This also lays the ground work for other configuration options in the future. This work was originally inspired from the #776 by @nick-donald.

Todos

• Tests
• Documentation
• Fix state leaking from tests

Related

Issue #776
Issue #573
Pull request #776

[codebycliff]

These tests all pass every time when I run just this file. However, these last two tests cause the entire suite to fail with an error about leaking a double. Due to it being a state leaking issue, it's not a consistent test that fails. The two different errors that keep seeing are:

and

I'm not sure how to go about fixing those as I'm not super familiar with the test setup on this project. I will continue to look into it, but could use some advice if someone has some.

[codebycliff]

I was able to fix this issue. The problem was that one of the tests in the build_strategy_spec.rb was stubbing a constant that was overriding the new class definition in the spec_helper.rb. The specific test that was stubbing was able to be re-written without mocks now that the ApplicationController class is defined. I believe the way I re-wrote the test still tests for the same functionality. Somebody correct me if that's not the case. The commit is here:
a886d28

[codebycliff]

This is ready for review now if anybody wants to take a look (e.g. @varyonic @seanlinsley @syguer). I added the new functionality to the dummy application as well to increase the code coverage.

[syguer]

Looks good! 👏

[syguer]

But I wonder why draper needs to depend on Controller layer... 🤔
Of course I know, we need a context of controller. I hope we can divide its dependency someday 😄

[codebycliff]

Yes, I agree. Maybe we can extract that dependency into optional functionality. The basic decorator pattern should be able to work without the need for a view context. But, baby steps for now..

[syguer]

👍