test: don't use deprecated way of capturing logs

[daipom]

Background

The next td-agent will embed Ruby 3.2.

I was checking each embedded plugin and noticed that this plugin has no GitHub CI.

I added CI to my forked repository, but I found the tests are unstable on Windows and macOS.

• https://github.com/daipom/fluent-plugin-flowcounter-simple/actions/runs/4239789791

So, I created this PR first.
Following this, I would like to create a PR to add GitHub CI.

About this fix

We should use Driver::logs instead of capture_log to fix unstable tests.

capture_log is defined by this plugin here.

fluent-plugin-flowcounter-simple/test/helper.rb

Lines 12 to 28 in 5081e88

	class Test::Unit::TestCase
	def capture_log(log)
	if defined?(Fluent::Test::TestLogger) and log.is_a?(Fluent::Test::TestLogger) # v0.14
	yield
	log.out.logs.join("\n")
	else
	begin
	tmp = log.out
	log.out = StringIO.new
	yield
	return log.out.string
	ensure
	log.out = tmp
	end
	end
	end
	end

However, this is for older versions as well as the following, and this makes tests unstable.

• https://github.com/fluent/fluentd/blob/6c649d189b5cf65ccfce58f6952a31b24c775e72/lib/fluent/test/helpers.rb#L110-L122

Reproduce failing tests

Windows seems to have the highest probability of failure.

• my forked repository's CI: https://github.com/daipom/fluent-plugin-flowcounter-simple/actions/runs/4239789791
• On my Windows10 Home machine
  • Ruby 3.2
  • Each test sometimes succeeds and sometimes does not.

  $ bundle
  $ bundle exec rake
  C:/Ruby32-x64/bin/ruby.exe -w -I"lib;lib;test" C:/Ruby32-x64/lib/ruby/gems/3.2.0/gems/rake-13.0.6/lib/rake/rake_test_loader.rb "test/plugin/test_filter_flowcounter_simple.rb" "test/plugin/test_out_flowcounter_simple.rb"
  C:/Ruby32-x64/lib/ruby/gems/3.2.0/gems/bundler-2.3.0/lib/bundler/vendor/thor/lib/thor/error.rb:105: warning: constant DidYouMean::SPELL_CHECKERS is deprecated
  Calling `DidYouMean::SPELL_CHECKERS.merge!(error_name => spell_checker)' has been deprecated. Please call `DidYouMean.correct_error(error_name, spell_checker)' instead.
  C:/Ruby32-x64/lib/ruby/gems/3.2.0/gems/serverengine-2.3.1/lib/serverengine/socket_manager_win.rb:140: warning: assigned but unused variable - type
  C:/Ruby32-x64/lib/ruby/gems/3.2.0/gems/cool.io-1.7.1/lib/iobuffer_ext.so: warning: method redefined; discarding old initialize
  C:/Ruby32-x64/lib/ruby/gems/3.2.0/gems/cool.io-1.7.1/lib/iobuffer_ext.so: warning: method redefined; discarding old clear
  C:/Ruby32-x64/lib/ruby/gems/3.2.0/gems/cool.io-1.7.1/lib/iobuffer_ext.so: warning: method redefined; discarding old empty?
  C:/Ruby32-x64/lib/ruby/gems/3.2.0/gems/cool.io-1.7.1/lib/iobuffer_ext.so: warning: method redefined; discarding old write
  C:/Ruby32-x64/lib/ruby/gems/3.2.0/gems/fluentd-1.15.3-x64-mingw-ucrt/lib/fluent/plugin_helper.rb:46: warning: method redefined; discarding old inherited
  C:/Ruby32-x64/lib/ruby/gems/3.2.0/gems/fluentd-1.15.3-x64-mingw-ucrt/lib/fluent/plugin_helper.rb:46: warning: previous definition of inherited was here
  Loaded suite C:/Ruby32-x64/lib/ruby/gems/3.2.0/gems/rake-13.0.6/lib/rake/rake_test_loader
  Started
  F
  ==============================================================================================================================================================================================================================================
        assert { out.include?("count:20") }
                 |   |
                 |   false
                 ""
  C:/Users/reang/Documents/work/fluentd/fluentdPlugins/fluent-plugin-flowcounter-simple/test/plugin/test_filter_flowcounter_simple.rb:30:in `test_filter'
       27:     d = create_driver
       28:     filtered, out = filter(d, msgs)
       29:     assert_equal msgs, filtered
    => 30:     assert { out.include?("count:20") }
       31:   end
       32:
       33:   private
  ==============================================================================================================================================================================================================================================....
  Finished in 0.5054875 seconds.
  ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------5 tests, 9 assertions, 1 failures, 0 errors, 0 pendings, 0 omissions, 0 notifications
  ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------9.89 tests/s, 17.80 assertions/s
  Command failed with status (1): [ruby -w -I"lib;lib;test" C:/Ruby32-x64/lib/ruby/gems/3.2.0/gems/rake-13.0.6/lib/rake/rake_test_loader.rb "test/plugin/test_filter_flowcounter_simple.rb" "test/plugin/test_out_flowcounter_simple.rb" ]
  
  Tasks: TOP => default => test
  (See full trace by running task with --trace)

[kou]

Could you improve the title of this pull request something like test: don't use deprecated capture_log?

[daipom]

Could you improve the title of this pull request something like test: don't use deprecated capture_log?

Thanks! That is more specific and easy to understand. Fixed.

[daipom]

I just rebased this branch to the latest master.

[daipom]

I thought that capture_log was the method of Fluentd, but it was wrong.

• https://github.com/fluent/fluentd/blob/6c649d189b5cf65ccfce58f6952a31b24c775e72/lib/fluent/test/helpers.rb#L110-L122

This method is defined by this plugin in helper.rb.

fluent-plugin-flowcounter-simple/test/helper.rb

Lines 12 to 28 in 5081e88

	class Test::Unit::TestCase
	def capture_log(log)
	if defined?(Fluent::Test::TestLogger) and log.is_a?(Fluent::Test::TestLogger) # v0.14
	yield
	log.out.logs.join("\n")
	else
	begin
	tmp = log.out
	log.out = StringIO.new
	yield
	return log.out.string
	ensure
	log.out = tmp
	end
	end
	end
	end

But this is very similar to the Fluentd method and should not be used.

I changed the title a little, and also fixed the helper.rb.

[daipom]

I have removed unnecessary codes from test/helper.rb.

[kou]

+1

[daipom]

Thanks for your review!