* FIX: Don't diplay character reference in HTML diffs
Before this change, HTML escaping was done before splitting text into
tokens, so token splitter saw literals like "'", and split them as
it was normal text into parts into ["&", "#", "39", ";"]. This caused
diff to display character references, as those tokens used separate
HTML tags to display their insertion/deletion status.
* Avoid making one element arrays while generating diffs
Since rspec-rails 3, the default installation creates two helper files:
* `spec_helper.rb`
* `rails_helper.rb`
`spec_helper.rb` is intended as a way of running specs that do not
require Rails, whereas `rails_helper.rb` loads Rails (as Discourse's
current `spec_helper.rb` does).
For more information:
https://www.relishapp.com/rspec/rspec-rails/docs/upgrade#default-helper-files
In this commit, I've simply replaced all instances of `spec_helper` with
`rails_helper`, and renamed the original `spec_helper.rb`.
This brings the Discourse project closer to the standard usage of RSpec
in a Rails app.
At present, every spec relies on loading Rails, but there are likely
many that don't need to. In a future pull request, I hope to introduce a
separate, minimal `spec_helper.rb` which can be used in tests which
don't rely on Rails.
