Add our reporter after other formatters added

[JuanitoFatas]

Paired with @matthewd.

@matthewd and I had this originally inside the before(:suite) block:

config.before(:suite) do
  if config.formatters.empty?
    config.add_formatter config.default_formatter
  end
  config.add_formatter RSpec::Buildkite::Insights::Reporter
end

but actually I found that in before(:suite), there are always config.formatters, so it is not necessary to add the default_formatter (those 3 if lines).

The problem of adding our reporter before the before(:suite) is that it is too early. The RSpec.config.formatters will be:

[RSpec::Buildkite::Insights::Reporter, RSpec::Core::Formatters::DeprecationFormatter, RSpec::Core::Formatters::FallbackMessageFormatter]

and RSpec does not do the magic of adding a doc formatter because it sees we already got a RSpec::Buildkite::Insights::Reporter and think it can report output.

While adding our reporter inside the before(:suite). The RSpec.config.formatters will be:

[RSpec::Core::Formatters::DocumentationFormatter, RSpec::Core::Formatters::DeprecationFormatter, RSpec::Buildkite::Insights::Reporter]

Because the spec_helper.rb from people’s app already done, config.formatters that is capable of reporting output should already exist. Adding our reporter then put us in the formatters array to report results, but the documentation formatter (or other user-sepecified formatter) will handle the output to Terminal for us 😉