How to Begin to Develop Ruby Core

1. The secrets of CRuby ecosystem How to Begin to Develop Ruby Core Hiroshi SHIBATA / GMO PEPABO inc. 2016.09.24 Euruko 2016

2. Chief Engineer Hiroshi SHIBATA @hsbt https://www.hsbt.org

3. self.introduce => { name: “SHIBATA Hiroshi”, nickname: “hsbt”, title: “Chief engineer at GMO Pepabo, Inc.”, commit_bits: [“ruby”, “rake”, “rubygems”, “rdoc”, “psych”, “syck”, “ruby- build”, “railsgirls”, “railsgirls-jp”, …], sites: [“hsbt.org”, “ruby-lang.org”, “rubyci.org”, “railsgirls.com”, “railsgirls.jp”], }

4. https://pepabo.com CEO(@kentarow) and CTO(@kentaro) support me

5. What’s (C)Ruby? 1.

6. Variation of Ruby Interpreter Implementation: • Ruby(MRI, CRuby) • JRuby • Rubinius • Opal ISO/IEC 30170:2012: • CRuby • mruby

7. Basis of CRuby and YARV “ Throughout most of this book we’ll learn about the original, standard implementation of Ruby, known as Matz’s Ruby Interpreter (MRI) after Yukihiro Matsumoto, who invented Ruby in 1993.” Ruby Under a Microscope, p.4 “ With Ruby 1.9, Koichi Sasada and the Ruby core team introduced Yet Another Ruby Virtual Machine (YARV), which actually executes your Ruby code.” Ruby Under a Microscope, p.33 Ruby 1.8 Ruby 1.9

8. Ruby Committer Heroku • Matz • ko1 • n0kada $ cat ~svn/.ssh/authorized_keys | awk '{print $5}' | sort | uniq | wc -l 93 Total 91 people + 2 bot MoneyForward • shyouhei Full-time commiters

9. Branch maintainers trunk known as 2.4 nurse: Release manager 2.3 nagachika: Stable branch maintainer 2.2, 2.1 unak: Old stable branch maintainer

10. Linux •akr •normalperson •n0kada and others Windows •unak •n0kada Platform maintainers BSD •nurse Solaris •ngoto OS X •n0kada •mrkn

11. Ruby Core Maintenance scope policy Language core features including security Yukihiro Matsumoto (matz) Ruby VM(YARV) Koichi Sasada (ko1) Core classes Ruby Commiters

12. Ruby Core Maintenance Policy Standard Libraries Each maintainers Bundled Libraries(default/bundled gems) Hiroshi SHIBATA(hsbt), Nobuyoshi Nakada(nobu) Documentation Zachary Scott(zzak)

13. *.ruby-lang.org www.ruby-lang.org Official Website of Ruby language. It’s hosted by Heroku. We welcomed to translate contribution. see http://github.com/ruby/www.ruby-lang.org svn.ruby-lang.org Main repository of Ruby source. bugs.ruby-lang.org Official issue tracker of Ruby. It’s hosted by Heroku

14. *.ruby-lang.org ftp.ruby-lang.org Site of distribute official package docs.ruby-lang.org Hosted document generated from RDoc and rubima project.

15. CDN Our site and package distribution were supported by fastly. • www.ruby-lang.org • cache.ruby-lang.org Statistics of our CDN: • Access ratio: USA: 37.9%, EU: 17.8%, Asia: 39.0%, Others: 5.3% • Bandwidth: 6181 GB/month • Requests: 12,296,848 req/month = 4 req/sec

16. What does mean “ofﬁcial”? “official” means “Matz controllable” Un-controllable examples: • ruby-doc.org • rubygems.org • bundler.io • rvm/rbenv/chruby

17. Licenses of Ruby language • 2-clause BSDL • Ruby License see details of `COPYING` ﬁle in ruby source code.

18. Ruby is OSS

19. Do submit your patch to OSS 2.

20. Contributing of OSS People say: “Contributing to OSS is easy! Please write some documentation and submit a patch!” You say: “Okay! I will contribute new documentation for Ruby!”

21. Documentation is hard • No-one knows the true behavior of OSS • Only author knows that. • Documentation is tedious work :bow: Because documentation is valuable work.

22. Testing and Running are easy I always start code reading with the following commands I pick out `before_script` and `script` code from .travis.yml and invoke it. For example: $ git clone https://github.com/some/gems $ cd gems $ less .travis.yml $ bundle install $ rake spec $ rake spec:plugins

23. In the case of ruby You will get… $ git clone https://github.com/ruby/ruby $ cd ruby $ less .travis.yml

24. .travis.yml in ruby/ruby before_script: - "uname -a" - "uname -r" - "rm -fr .ext autom4te.cache" - "echo $TERM" - "make -f common.mk BASERUBY=ruby MAKEDIRS='mkdir -p' srcdir=. update-config_files" - "autoconf" - "mkdir config_1st config_2nd" - "./configure -C --disable-install-doc --with-gcc=$CC $CONFIG_FLAG" - "cp -pr config.status .ext/include config_1st" - "make reconfig" - "cp -pr config.status .ext/include config_2nd" - "diff -ru config_1st config_2nd" - "make after-update BASERUBY=ruby" - "make -s $JOBS" - "make update-rubyspec" script: - "make test TESTOPTS=--color=never" - "make test-all TESTOPTS='-q -j3 --color=never --job-status=normal'" - "make test-rubyspec MSPECOPT=-fm"

25. How to contribute to OSS Ruby

26. Do submit your patch to ruby core 1. Write code :) 2. Run tests 3. Open bugs.ruby-lang.org and create new account 4. Open https://bugs.ruby-lang.org/projects/ruby-trunk/issues/new 5. Attach your code and write description of your proposal 6. Press “submit”

27. Do submit your patch to ruby core 1. Write code :) 2. Run tests 3. Open bugs.ruby-lang.org and create new account 4. Open https://bugs.ruby-lang.org/projects/ruby-trunk/issues/new 5. Attach your code and write description of your proposal 6. Press “submit”

28. Test ruby language 3.

29. Start to test Ruby language $ git clone https://github.com/ruby/ruby $ cd ruby $ autoconf $ ./conﬁgure —disable-install-doc $ make -j $ make check You can invoke language tests with the following instructions:

30. % make check TESTS=‘-j4’ (snip) PASS all 1010 tests exec ./miniruby -I./lib -I. -I.ext/common ./tool/runruby.rb --extout=.ext -- --disable-gems "./bootstraptest/runner.rb" --ruby="ruby --disable-gems" ./KNOWNBUGS.rb 2016-06-18 15:42:02 +0900 Driver is ruby 2.4.0dev (2016-06-18 trunk 55440) [x86_64-darwin15] Target is ruby 2.4.0dev (2016-06-18 trunk 55440) [x86_64-darwin15] last_commit=* test/rubygems/test_gem_installer.rb: Fixed broken test with extension build. https://github.com/rubygems/rubygems/pull/1645 KNOWNBUGS.rb PASS 0 No tests, no problem test succeeded Run options: "--ruby=./miniruby -I./lib -I. -I.ext/common ./tool/runruby.rb --extout=.ext -- --disable-gems" # Running tests: Finished tests in 2.513254s, 87.9338 tests/s, 177.4592 assertions/s. 221 tests, 446 assertions, 0 failures, 0 errors, 0 skips ruby -v: ruby 2.4.0dev (2016-06-18 trunk 55440) [x86_64-darwin15] Run options: "--ruby=./miniruby -I./lib -I. -I.ext/common ./tool/runruby.rb --extout=.ext -- --disable-gems" --excludes-dir=./test/excludes --name=!/ memory_leak/ --exclude=/testunit/ --exclude=/minitest/ -j4 # Running tests: [ 89/803] 4625=test_bigdecimal 4626=test_table 4627=test_encodings 4628=test_bug_reporter

31. common.mk • check/check-ruby • btest/btest-ruby • test-basic/test-knownbug • test-testframework • test • test-all • test-almost • test-ruby • test-rubyspec

32. make test • btest-ruby • snip for next slides • test-basic • invoke `basictest/runner.rb` with target ruby • test-knownbug • invoke `KNOWNBUGS.rb` • It’s empty a lot of the time.

33. make btest-ruby % ls bootstraptest pending.rb runner.rb* test_attr.rb test_autoload.rb test_block.rb test_class.rb test_eval.rb test_exception.rb test_finalizer.rb test_flip.rb test_flow.rb test_fork.rb test_gc.rb test_io.rb test_jump.rb test_literal.rb test_literal_suffix.rb test_load.rb test_marshal.rb test_massign.rb test_method.rb test_objectspace.rb test_proc.rb test_string.rb test_struct.rb test_syntax.rb test_thread.rb What’s `bootstraptest/runner.rb` ? • load test files and invoke them • define assertion methods like àssert_equal` etc.

34. `cat bootstraptest/test_class.rb` assert_equal 'true', %q( class C; end Object.const_deﬁned?(:C) ) assert_equal 'Class', %q( class C; end C.class ) (snip) assert_equal 'Class', %q( class A; end class C < A; end C.class ) (snip) assert_equal 'M', %q( module M; end M.name ) (snip) assert_equal 'A::B', %q( class A; end class A::B; end A::B )

35. test-basic a, = nil; test_ok(a == nil) a, = 1; test_ok(a == 1) a, = []; test_ok(a == nil) (snip) def r; return *[]; end; a = r(); test_ok(a == []) def r; return *[1]; end; a = r(); test_ok(a == [1]) def r; return *[nil]; end; a = r(); test_ok(a == [nil]) (snip) f = lambda { |a, b=42, *c| [a,b,c] } test_ok(f.call(1 ) == [1,42,[ ]] ) test_ok(f.call(1,43 ) == [1,43,[ ]] ) test_ok(f.call(1,43,44) == [1,43,[44]] ) (snip)

36. These are for Developer of VM/GC/Syntax/etc

37. make test-all test-all invokes test files under the `test` directory. test-all has some options for testing: • make test-all TESTS=“logger” • test only files under `test/logger` • make test-all TESTS=“-j4” • it make parallel execution with 4 processes.

38. cat `test/ruby/test_array.rb` % cat test/ruby/test_array.rb # coding: US-ASCII require 'test/unit' class TestArray < Test::Unit::TestCase (snip) def test_percent_i assert_equal([:foo, :bar], %i[foo bar]) assert_equal([:""foo"], %i["foo]) end def test_0_literal assert_equal([1, 2, 3, 4], [1, 2] + [3, 4]) assert_equal([1, 2, 1, 2], [1, 2] * 2) assert_equal("1:2", [1, 2] * ":") (snip)

39. cat `test/logger/test_logger.rb` % cat test/logger/test_logger.rb # coding: US-ASCII require 'test/unit' require 'logger' require 'tempﬁle' class TestLogger < Test::Unit::TestCase (snip) def test_add logger = Logger.new(nil) logger.progname = "my_progname" assert(logger.add(INFO)) log = log_add(logger, nil, "msg") assert_equal("ANY", log.severity) assert_equal("my_progname", log.progname) (snip)

40. cat `test/-ext-/array/test_resize.rb` % cat ext/-test-/array/resize/resize.c #include "ruby/ruby.h" static VALUE ary_resize(VALUE ary, VALUE len) { rb_ary_resize(ary, NUM2LONG(len)); return ary; } void Init_resize(void) { rb_deﬁne_method(rb_cArray, "__resize__", ary_resize, 1); } require 'test/unit' require '-test-/array/resize' class TestArray < Test::Unit::TestCase class TestResize < Test::Unit::TestCase def test_expand feature = '[ruby-dev:42912]' ary = [*1..10] ary.__resize__(10) assert_equal(10, ary.size, feature) assert_equal([*1..10], ary, feature) ary.__resize__(100) assert_equal(100, ary.size, feature) (snip)

41. These are for “you”

42. make check make check depends on the following definitions: • main • build encodings and extensions. • test • test-testframework • run tests for `testunit` and `minitest` • test-almost • run tests under `test` excluding `testunit` and `minitest`

43. test-unit/minitest

44. Why separated the test framework? The following libraries uses minitest directly in Ruby 2.3: • rubygems • rdoc Other libraries uses test-unit. rubygems and rdoc are developed at github.com/rubygems/rubygems and github.com/rdoc/rdoc. We need to support these libraries and their tests.

45. How to merge upstream from others I merged upstream into ruby/ruby periodically using following instructions. ruby and rubygems guarantee to work to test and code each other. it’s the same situation for ruby and rdoc $ git clone https://github.com/ruby/ruby $ git clone https://github.com/rubygems/rubygems $ cd ruby $ rm -rf lib/rubygems test/rubygtems lib/rubygems.rb $ cp -rf ../../rubygems/rubygems/lib/rubygems ./lib $ cp -rf ../../rubygems/rubygems/lib/rubygems.rb ./lib $ cp -rf ../../rubygems/rubygems/test/rubygems ./test $ git checkout lib/rubygems/LICENSE.txt

46. backport is hard rubygems still supports Ruby 1.8. % g show a34fb569e41cd87866e644d92a9df4be89b3cad2 test/rubygems/test_gem_package.rb commit a34fb569e41cd87866e644d92a9df4be89b3cad2 Author: Eric Hodel <drbrain@segment7.net> (snip) --- test/rubygems/test_gem_package.rb +++ test/rubygems/test_gem_package.rb @@ -638,7 +638,7 @@ class TestGemPackage < Gem::Package::TarTestCase e.message io end - tf.close! + tf.close! if tf.respond_to? :close! end def test_verify_empty

47. ruby/spec

48. RubySpec Q. What’s rubyspec? A. RubySpec is an executable specification for the Ruby programming language. “Matz's Ruby Developers Don't Use RubySpec and It's Hurting Ruby” http://rubini.us/2014/12/31/matz-s-ruby-developers-don-t-use-rubyspec/ “ruby/spec” is not a “specification”. It’s actually a set of “test”. The only real ruby specification is inside of Matz :)

49. make test-rubyspec CRuby has `make update-rubyspec` and `make test-rubyspec` tasks. •`make update-rubyspec` • pulls ruby/rubyspec and ruby/mspec into the spec directory. •`make test-rubyspec` • invokes mspec with the ruby binary and the latest rubyspecs.

50. cat spec/rubyspec/core/string/append_spec.rb % cat spec/rubyspec/core/string/concat_spec.rb require File.expand_path('../../../spec_helper', __FILE__) require File.expand_path('../ﬁxtures/classes', __FILE__) require File.expand_path('../shared/concat', __FILE__) describe "String#<<" do it_behaves_like :string_concat, :<< it_behaves_like :string_concat_encoding, :<< end % cat spec/rubyspec/core/string/shared/concat.rb describe :string_concat, shared: true do it "concatenates the given argument to self and returns self" do str = 'hello ' str.send(@method, 'world').should equal(str) str.should == "hello world" end (snip) Please check details: https://github.com/ruby/spec

51. rubyspec and mspec We approved new or updated examples at github.com/ruby/spec. @headius wrote: “So nice to see RubySpec getting a steady stream of Ruby 2.3 specs.” https://twitter.com/headius/status/667793518098673664 A lot of contributors submitted new specs for Ruby 2.3 and 2.4 features.

52. test coverage % make update-coverage updating simplecov ... remote: Counting objects: 90, done. (snip) updating simplecov-html ... updating doclie … % COVERAGE=1 make test-all TESTS=webrick I added a coverage task using simplecov You can get coverage results for `webrick` under the coverage directory.

53. Please contribute tests to ruby $ git clone https://github.com/ruby/ruby $ cd ruby $ autoconf $ ./conﬁgure —disable-install-doc $ make -j $ make check You can invoke focused tests with coverage: $ COVERAGE=1 make test-all TESTS=“logger” $ open coverage/index.html You can code new tests or update existing tests. and submit it.

54. Ruby (language) testing is so easy

55. How request Ruby core 4.

56. Feature request • We need to focus “Use case” than “function”. • We need to attach patch to feature request. • We need Matz approval.

57. Acceptable requests without usecase • Symmetrical: `Array#shift`, `Array#unshift` • POSIX Socket.gethostbyname • [BUG] [SEGV]

58. Bug report • We need minimum reproduction code • We need to describe expected/unexpected behavior • We need to attach crash log • We need to try different version of ruby

59. Issue tracker Our official tracker is “bugs.ruby-lang.org” Mailing list integration •https://github.com/ruby/redmine_* •This behavior is same as github Continuous Upgrade Ruby and Rails to latest version.

60. Redmine vs GitHub github.com/ruby/ruby is ok for ruby core team [CAUTION] If you hope to ask new feature to Matz, You need to submit bugs.ruby-lang.org . Matz is only available on redmine. Why Ruby does not use GitHub? • GitHub is proprietary service • ruby committers do not have problem with redmine • We start to consider issue of “Why Ruby does not use Git”

61. Monthly Developer Meeting We hope to increase to transparency for Ruby development process. One of our challenges is “Developer Meeting”. It’s open discussion time for feature and issue of Ruby every months. [ruby-core:69550]: https://bugs.ruby-lang.org/projects/ruby/wiki/ DevelopersMeeting20150728Japan

62. Gemiﬁcation for stdlib • We extract old or un-maintain status stdlibs like net-telnet, xmlrpc, tk to bundled gems. • These are extracted under the https://github.com/ruby/ . And shipped on rubygems.org • Date, CGI, Readline are also extracted at the future(It’s my ideas). • OpenSSL is also extracted default gems. You can update it separated ruby core releases same as rubygems, rdoc, bigdecimal

63. How develop Ruby core 5.

64. Ruby CI

65. What’s Ruby CI Ruby CI is a CI results collector for alternative platforms • http://rubyci.org • https://github.com/nurse/rubyci • https://github.com/ruby/chkbuild Ruby CI goal is entirely supports all of Ruby platform. We can detect a lot of build fails using Ruby CI. It has 2 or 3 versions every linux distribution and BSD, Windows, OS X, Solaris Environments.

66. How to add a new server You can add your server to rubyci.org Requirements: • not yet supported platforms. • ex. linux with ARM, *BSD, icc with OSX, Windows • periodically running every day • It must be possible to access to AWS S3 You should check the following commands on your server $ git clone https://github.com/akr/chkbuild $ cd chkbuild $ ruby start-build

67. Version number and release cycle We plan to release every christmas. • 2.1.0: 2013/12/25 • 2.2.0: 2014/12/25 • 2.3.0: 2015/12/25 • 2.4.0: 2016/12/25(TBD)

68. Ruby core backport model trunk ruby_2_1 ruby_2_0_0 trunk ruby_2_1 ruby_2_0_0 We backport fixes to stable branch from trunk. We do not merge fixes to trunk from stable branch

69. Release management We will release new version of Ruby at “Release Day” by @narse There is no exception to this rule. • If we have incompletion issue or feature, we will revert it. • If we don’t have enough discussion for some issue, we don’t merge or implement it into new version of ruby. • If we found some regression, we need to fix it or revert to related code or issue.

70. Security release We have “security@ruby-lang.org” for security report. We received buffer overflow, memory leak, escape string etc etc… We hard to fix and release these security issue. so all of release maintainer are volunteer work. Our release delayed by preparing new releases of stable and old stable version.

71. HackerOne We’ve been use https://hackerone.com/ruby It has bounty program provided by IBB. We accepts to security report via hackerone too.

72. Conclusion

73. CRuby secrets •Who develop CRuby •Where is ofﬁcial resource of CRuby •How to develop CRuby •What is important of feature request in CRuby •When release new version of CRuby and…

74. Why use Ruby?

75. “Ruby is designed to make programmers happy.”