Enforce spec file names have _spec.rb suffix

[eliotsykes]

Specs without _spec.rb suffix will not be run by bare bin/rspec (no path)

# spec/support/spec_file_name_enforcer.rb
RSpec.configure do |config|
  config.before(:suite) do

    files_without_spec_suffix = Dir.glob('spec/**/*').select do |filename|
      File.file?(filename) && 
        !filename.match(/_spec\.rb\z/) &&
        !filename.match(%r{\Aspec/(support|factories|mailers/previews)/}) &&
        !filename.match(%r{\Aspec/(spec_helper\.rb|rails_helper\.rb|examples\.txt)\z})
    end

    if files_without_spec_suffix.any?
      raise 'Spec files need _spec.rb suffix: ' + files_without_spec_suffix.join(', ')
    end
  end
end