Testing with RSpec

[ixti]

Seen recent addition to docs and recalled that recently we've done this in our specs (I don't think that one should stub logger when it's possible to not to):

require "semantic_logger"

module LoggableTesting
  class Appender < SemanticLogger::Subscriber
    include Singleton

    attr_reader :events

    def initialize
      super
      @events = []
    end

    def log(event)
      @events << event
      true
    end

    def flush
      @events.clear
      true
    end

    def close
      flush
      self
    end
  end

  def captured_log_events
    Appender.instance.events.dup
  end
end

RSpec.configure do |config|
  config.include LoggableTesting

  config.before(:suite) { SemanticLogger.sync! }

  config.before do
    LoggableTesting::Appender.instance.flush
    SemanticLogger.add_appender(appender: LoggableTesting::Appender.instance)
  end

  config.after do
    SemanticLogger.remove_appender(LoggableTesting::Appender.instance)
  end
end

With this approach we can do:

it "logs error" do
  Rails.logger.info("tada!")

  expect(captured_log_events).to include(have_attributes(
    name:    "Rails",
    level:   :info,
    message: "tada"
  ))
end