Expose 'with default RSpec/Language config' to consumers

[smcgivern]

This helper is essential for anyone writing their own RSpec cops based on RuboCop::Cop::RSpec::Base, because it now requires a minimal config to even run the cop.

The wordy file name is because the RuboCop gem already defines rubocop/rspec/shared_contexts, and we don't want to shadow that. This means that consumers of this library who want to write a spec for a cop based on RuboCop::Cop::RSpec::Base will need something like this in spec/spec_helper.rb:

require 'rubocop/rspec/shared_contexts/default_rspec_language_config_context'

RSpec.config do |config|
  # ...
  # Add metadata as appropriate
  config.include_context 'with default RSpec/Language config'
end

This was suggested in the PR that introduced this feature: https://github.com/rubocop/rubocop-rspec/pull/956/files#r515643915

We don't enforce using alias configuration, and custom cops can continue to use their own configuration until someone decides to follow the mainstream, and would like to contribute by extracting this somewhere to lib/.

fixes #1418

Before submitting the PR make sure the following are checked:

• Feature branch is up-to-date with master (if not - rebase it).
• Squashed related commits together.
• Added tests.
• Updated documentation.
• Added an entry to the CHANGELOG.md if the new code introduces user-observable changes.
• The build (bundle exec rake) passes (be sure to run this locally, since it may produce updated documentation that you will need to commit).

[smcgivern]

Updated documentation.

I'd like to do this, but I wasn't sure where. Maybe https://github.com/rubocop/rubocop-rspec/blob/master/docs/modules/ROOT/pages/upgrade_to_version_2.adoc?

[smcgivern]

I tested this on a library we have that uses rubocop-rspec and it worked for me: https://gitlab.com/gitlab-org/ruby/gems/gitlab-styles/-/merge_requests/119#note_1092839680

[pirj]

Maybe https://github.com/rubocop/rubocop-rspec/blob/master/docs/modules/ROOT/pages/upgrade_to_version_2.adoc?

Yes, or add a section similar to RuboCop's https://docs.rubocop.org/rubocop/development.html

[pirj]

Thank you!
Appreciate if you could add some docs.

[smcgivern]

Thanks @pirj, I added some brief development documentation. (Rendered: https://github.com/smcgivern/rubocop-rspec/blob/ad674c8ee2a55a48f933a4605d9145daaa83c7ba/docs/modules/ROOT/pages/development.adoc)

I am not sure what the documentation guidelines are here, so I'm happy to take any and all suggestions there.

[bquorning]

I have renamed some of the required CI checks, which unfortunately means that you will need to rebase this branch to make CI pass.

[smcgivern]

Thanks, done.

[pirj]

Rebased and moved the changelist item up to the master section.

[tdeo]

Fixes #1418, sorry I hadn't look before opening that issue, and thans for adding this support

[tdeo]

I tried using this branch of rubocop-rspec and it works perfectly for my use-case, following the suggestions in the doc for the setup of metadata and automatic context inclusion is spot on 👌

Otherwise it seems that the CI got stuck here, maybe you can try rebasing on top of master to re-trigger it?

[smcgivern]

@tdeo thanks for trying it out!

I rebased because the CHANGELOG had conflicts, but the workflows need a maintainer to approve before they run:

[pirj]

Green!

[pirj]

@smcgivern May I ask you to rebase and make sure Changelog is in order?

[smcgivern]

@pirj sorry for the push spam, I didn't fix the CHANGELOG properly first time around. This is up to date now.

[pirj]

Thank you, @smcgivern !

[smcgivern]

Thanks @pirj! I look forward to deleting this file from our repos when this is release 😃

[pirj]

Released in 2.15.0, @smcgivern