RailsConf 2015 - Breaking Down the Barrier: Demystifying Contributing to Rails

http://confreaks.tv/videos/railsconf2015-breaking-down-the-barrier-demystifying-contributing-to-rails

Contributing to Rails for the first time can be terrifying. In this lab I’ll make contributing to Rails more approachable by going over the contributing guidelines and technical details you need to know. We’ll walk through traversing the source code with tools such as CTags, source_location and TracePoint. Additionally, we’ll create reproduction scripts for reporting issues and learn advanced git commands like bisect and squash. At the end of this session you’ll have the confidence to fix bugs and add features to Ruby on Rails.

Transcript

1. CLONE THE REPO Grab a USB or clone the railsconf_scripts repo from https://github.com/eileencodes/railsconf_scripts.git $ cd railsconf_scripts # mac/linux users $ bundle install --local # windows users not using a linux VM $ git checkout windows $ bundle install --local
2. BREAKING DOWN THE Demystifying Contributing to Ruby on Rails BARRIER:
3. EILEEN M. UCHITELLE Programmer at Basecamp ! eileencodes.com " @eileencodes # @eileencodes
5. Kingston, New York
6. Arya @aryadog
7. PREREQUISITES
8. GOALS
9. to Rails can be INTIMIDATING. CONTRIBUTING
10. to Rails open source can be is INTIMIDATING. CONTRIBUTING #
11. FORMAT
12. CLONE THE REPO Grab a USB or clone the railsconf_scripts repo from github.com/eileencodes/railsconf_scripts $ cd railsconf_scripts/ # mac/linux users $ bundle install --local # windows users not using a linux VM $ git checkout windows $ bundle install --local
13. ENVIRONMENT REQUIREMENTS
14. ENVIRONMENT $ Ruby version manager (rbenv, rvm, chruby) $ Ruby 2.2.2
16. % Ruby version manager (rbenv, rvm, chruby) % Ruby 2.2.2 $ Databases for Active Record $ MySQL $ PostgreSQL $ SQLite3 ENVIRONMENT
17. % Ruby version manager (rbenv, rvm, chruby) % Ruby 2.2.2 % Databases for Active Record % MySQL % PostgreSQL % SQLite3 $ Git & a GitHub Account ENVIRONMENT
18. RUNNING THE TEST SUITE
20. RUNNING TESTS $ cd actionpack $ rake test Finished in 3.237796s, 861.0796 runs/ s, 4508.3137 assertions/s.
 2788 runs, 14597 assertions, 0 failures, 0 errors, 0 skips
21. ACTIVE RECORD $ cd activerecord $ rake test:sqlite3 $ rake test:mysql2 $ rake test:mysql $ rake test:postgresql
22. $ ruby -Ilib:test path/to/test_file.rb RUN A TEST FILE
23. $ ruby -Ilib:test path/to/test_file.rb -n test_name_of_test RUN A SINGLE TEST
24. RUN A SINGLE TEST $ ARCONN=mysql2 ruby -Ilib:test path/ to/test_file.rb -n test_name_of_test
25. $ bundle exec rake TEST=path/to/ test_file.rb -n test_name RUN A SINGLE TEST
26. $ cd activerecord/ $ rake test:sqlite3 $ ruby -Ilib:test test/cases/ reflection_test.rb $ ARCONN=mysql2 ruby -Ilib:test test/ cases/reflection_test.rb -n test_columns RUNNING TESTS
27. GUIDELINES FOR OPENING AN ISSUE
28. OPENING AN ISSUE $ Be clear and include the Rails version
29. OPENING AN ISSUE % Be clear and include the Rails version $ Don’t open security issues on the issues tracker
30. security@rubyonrails.org
31. OPENING AN ISSUE % Be clear and include the Rails version % Don’t open security issues on the issues tracker $ Don’t open issues that aren’t a bug in Rails
32. OPENING AN ISSUE % Be clear and include the Rails version % Don’t open security issues on the issues tracker % Don’t open issues that aren’t a bug in Rails $ Don’t open a separate issue if you have a PR
33. OPENING AN ISSUE % Be clear and include the Rails version % Don’t open security issues on the issues tracker % Don’t open issues that aren’t a bug in Rails % Don’t open a separate issue if you have a PR $ Don’t open feature request tickets
34. OPENING AN ISSUE % Be clear and include the Rails version % Don’t open security issues on the issues tracker % Don’t open issues that aren’t a bug in Rails % Don’t open a separate issue if you have a PR % Don’t open feature request tickets % Do include a test script or application
35. Examples of executable scripts github.com/rails/rails/blob/master/ guides/bug_report_templates TEST SCRIPTS
36. $ cd railsconf_scripts/ $ open ar_script_example.rb TEST SCRIPTS
37. require 'active_record' require 'minitest/autorun' require 'logger' ActiveRecord::Base.establish_connection(adapter: 'sqlite3', database: ':memory:') ActiveRecord::Base.logger = Logger.new(STDOUT) ActiveRecord::Schema.define do create_table :projects do |t| t.string :name end end class Project < ActiveRecord::Base validates_presence_of :name end class BugTest < Minitest::Test def test_assert project = Project.create! assert_not_operator project, :valid? end end
38. require 'active_record' require 'minitest/autorun' require 'logger' ActiveRecord::Base.establish_connection(adapter: 'sqlite3', database: ':memory:') ActiveRecord::Base.logger = Logger.new(STDOUT) ActiveRecord::Schema.define do create_table :projects do |t| t.string :name end end class Project < ActiveRecord::Base validates_presence_of :name end class BugTest < Minitest::Test def test_assert project = Project.create! assert_not_operator project, :valid? end end
39. require 'active_record' require 'minitest/autorun' require 'logger' ActiveRecord::Base.establish_connection(adapter: 'sqlite3', database: ':memory:') ActiveRecord::Base.logger = Logger.new(STDOUT) ActiveRecord::Schema.define do create_table :projects do |t| t.string :name end end class Project < ActiveRecord::Base validates_presence_of :name end class BugTest < Minitest::Test def test_assert project = Project.create! assert_not_operator project, :valid? end end
40. require 'active_record' require 'minitest/autorun' require 'logger' ActiveRecord::Base.establish_connection(adapter: 'sqlite3', database: ':memory:') ActiveRecord::Base.logger = Logger.new(STDOUT) ActiveRecord::Schema.define do create_table :projects do |t| t.string :name end end class Project < ActiveRecord::Base validates_presence_of :name end class BugTest < Minitest::Test def test_assert project = Project.create! assert_not_operator project, :valid? end end
41. require 'active_record' require 'minitest/autorun' require 'logger' ActiveRecord::Base.establish_connection(adapter: 'sqlite3', database: ':memory:') ActiveRecord::Base.logger = Logger.new(STDOUT) ActiveRecord::Schema.define do create_table :projects do |t| t.string :name end end class Project < ActiveRecord::Base validates_presence_of :name end class BugTest < Minitest::Test def test_assert project = Project.create! assert_not_operator project, :valid? end end
42. require 'active_record' require 'minitest/autorun' require 'logger' ActiveRecord::Base.establish_connection(adapter: 'sqlite3', database: ':memory:') ActiveRecord::Base.logger = Logger.new(STDOUT) ActiveRecord::Schema.define do create_table :projects do |t| t.string :name end end class Project < ActiveRecord::Base validates_presence_of :name end class BugTest < Minitest::Test def test_assert project = Project.create! assert_not_operator project, :valid? end end
43. require 'active_record' require 'minitest/autorun' require 'logger' ActiveRecord::Base.establish_connection(adapter: 'sqlite3', database: ':memory:') ActiveRecord::Base.logger = Logger.new(STDOUT) ActiveRecord::Schema.define do create_table :projects do |t| t.string :name end end class Project < ActiveRecord::Base validates_presence_of :name end class BugTest < Minitest::Test def test_assert project = Project.create! assert_not_operator project, :valid? end end
44. TEST SCRIPTS $ cd railsconf_scripts/ $ bundle exec ruby ar_script_example.rb
45. GUIDELINES FOR OPENING A PULL REQUEST
46. OPENING A PR $ Open PR’s against master
47. OPENING A PR % Open PR’s against master $ We don’t accept “cosmetic changes”
48. OPENING A PR % Open PR’s against master % We don’t accept “cosmetic changes” $ Write clear and descriptive commit messages
49. Short (50 chars or less) summary of changes More detailed explanatory text, if necessary. Wrap it to about 72 characters or so. In some contexts, the first line is treated as the subject of an email and the rest of the text as the body. The blank line separating the summary from the body is critical (unless you omit the body entirely); tools like rebase can get confused if you run the two together. Further paragraphs come after blank lines. - Bullet points are okay, too - Typically a hyphen or asterisk is used for the bullet, preceded by a single space, with blank lines in between, but conventions vary here
50. OPENING A PR % Open PR’s against master % We don’t accept “cosmetic changes” % Write clear and descriptive commit messages $ Be prepared to squash your commits
51. OPENING A PR % Open PR’s against master % We don’t accept “cosmetic changes” % Write clear and descriptive commit messages % Be prepared to squash your commits $ Don’t ping constantly or litter PR’s with +1’s
53. OPENING A PR % Open PR’s against master % We don’t accept “cosmetic changes” % Write clear and descriptive commit messages % Be prepared to squash your commits % Don’t ping constantly or litter PR’s with +1’s $ We <3 documentation PR’s
54. commit 02d3a253610eaf9c80587913b366e3fa0f56b71f Author: eileencodes <eileencodes@gmail.com> Date: Sat Oct 4 11:19:37 2014 -0400 [ci skip] Clarify deletion strategies for collection proxies For detailed testing of behavior see: https://gist.github.com/eileencodes/ 5b0a2fe011dcff6203fe This shows destroy_all always destroys records and fires callbacks. It will never use nullify or delete_all delete_all's behavior varies greatly based on `hm` vs `hm:t` and deletion strategy.
55. OPENING A PR % Open PR’s against master % We don’t accept “cosmetic changes” % Write clear and descriptive commit messages % Be prepared to squash your commits % Don’t ping constantly or litter PR’s with +1’s % We <3 documentation PR’s $ Keep it simple
56. OPENING A PR % Open PR’s against master % We don’t accept “cosmetic changes” % Write clear and descriptive commit messages % Be prepared to squash your commits % Don’t ping constantly or litter PR’s with +1’s % We <3 documentation PR’s % Keep it simple $ Use Benchmark/ips
57. $ cd railsconf_scripts/ $ open benchmark_ips_example.rb BENCHMARK/IPS
58. # railsconf_scripts/benchmark_ips_example.rb require 'benchmark/ips' ARRAY = (1..100).to_a def slow ARRAY.shuffle.first end def fast ARRAY.sample end Benchmark.ips do |x| x.report('slow') { slow } x.report('fast') { fast } x.compare! end
59. # railsconf_scripts/benchmark_ips_example.rb require 'benchmark/ips' ARRAY = (1..100).to_a def slow ARRAY.shuffle.first end def fast ARRAY.sample end Benchmark.ips do |x| x.report('slow') { slow } x.report('fast') { fast } x.compare! end
60. # railsconf_scripts/benchmark_ips_example.rb require 'benchmark/ips' ARRAY = (1..100).to_a def slow ARRAY.shuffle.first end def fast ARRAY.sample end Benchmark.ips do |x| x.report('slow') { slow } x.report('fast') { fast } x.compare! end
61. # railsconf_scripts/benchmark_ips_example.rb require 'benchmark/ips' ARRAY = (1..100).to_a def slow ARRAY.shuffle.first end def fast ARRAY.sample end Benchmark.ips do |x| x.report('slow') { slow } x.report('fast') { fast } x.compare! end
62. $ bundle exec ruby benchmark_ips_example.rb Calculating ------------------------------------- slow 26.801k i/100ms fast 131.410k i/100ms ------------------------------------------------- slow 343.594k (± 5.4%) i/s - 1.715M fast 6.348M (±11.8%) i/s - 31.276M Comparison: fast: 6347552.5 i/s slow: 343594.2 i/s - 18.47x slower
63. $ cd railsconf_scripts/ $ bundle exec ruby BENCHMARK/IPS benchmark_ips_example.rb
64. OPENING A PR % Open PR’s against master % We don’t accept “cosmetic changes” % Write clear and descriptive commit messages % Be prepared to squash your commits % Don’t ping constantly or litter PR’s with +1’s % We <3 documentation PR’s % Keep it simple % Use Benchmark/ips $ Write tests
65. WORKING WITH DEPRECATIONS
66. # nodoc example from activerecord/lib/active_record/ reflection.rb:588 class HasManyReflection < AssociationReflection # :nodoc: def initialize(name, scope, options, active_record) super(name, scope, options, active_record) end def macro; :has_many; end def collection?; true; end end
67. # Deprecation from activerecord/lib/active_record/tasks/ # database_tasks.rb:207 def load_schema_for(*args) ActiveSupport::Deprecation.warn(<<-MSG.squish) This method was renamed to `#load_schema` and will be removed in the future. Use `#load_schema` instead. MSG load_schema(*args) end
68. TRAVERSING UNFAMILIAR CODE
70. # actionview/lib/action_view/template/error.rb:118 def source_location if line_number "on line ##{line_number} of " else 'in ' end + file_name end
71. SOURCE LOCATION $ cd railsconf_scripts/ $ open source_location.rb
72. class Project < ActiveRecord::Base has_many :projects end class Comment < ActiveRecord::Base belongs_to :project end class BugTest < Minitest::Test def test_delete_all post = Post.create!(title: "Post title", content: "Lots of content") comment = Comment.create!(content: "I am a comment", post_id: post.id) assert 1, post.comments.count post.comments.delete_all assert 0, post.comments.count end end
73. class Project < ActiveRecord::Base has_many :projects end class Comment < ActiveRecord::Base belongs_to :project end class BugTest < Minitest::Test def test_delete_all post = Post.create!(title: "Post title", content: "Lots of content") comment = Comment.create!(content: "I am a comment", post_id: post.id) assert 1, post.comments.count puts post.comments.method(:delete_all).source_location assert 0, post.comments.count end end
74. SOURCE LOCATION $ cd railsconf_scripts/ $ bundle exec ruby source_location.rb
75. (0.0ms) begin transaction SQL (0.1ms) INSERT INTO "comments" ("content", "post_id") VALUES (?, ?) [["content", "I am a comment"], ["post_id", 1]] (0.0ms) commit transaction (0.1ms) SELECT COUNT(*) FROM "comments" WHERE "comments"."post_id" = ? [["post_id", 1]] .../activerecord/lib/active_record/associations/ collection_proxy.rb 442 (0.0ms) SELECT COUNT(*) FROM "comments" WHERE "comments"."post_id" = ? [["post_id", 1]]
76. # activerecord/lib/active_record/associations/ collection_proxy.rb:442 def delete_all(dependent = nil) @association.delete_all(dependent) end
77. CTags # OS X $ brew install ctags # Debian-based linux $ sudo apt-get install exuberant-ctags # Red Hat-based linux $ sudo yum install ctags
78. CTags $ cd path/to/rails/ $ ctags -R .
79. CTags $ cd path/to/rails/ $ ctags -R -f .git/tags .
80. CTags Sublime: github.com/SublimeText/CTags TextMate: github.com/textmate/ ctags.tmbundle
81. # .vimrc map <Leader>rt :!ctags --tag-relative --extra=+f - Rf.git/tags --exclude=.git,pkg —languages=- javascript,sql<CR><CR> set tags+=.git/tags
82. CTags $ CTRL + ]
83. CTags $ :ts
84. CTags $ :ts $ N + ENTER
86. # activerecord/lib/active_record/reflection.rb:314 def association_primary_key(klass = nil) options[:primary_key] || primary_key(klass || self.klass) end
87. # activerecord/lib/active_record/reflection.rb:314 def association_primary_key(klass = nil) puts caller options[:primary_key] || primary_key(klass || self.klass) end
88. .../through_association.rb:48:in `construct_join_attributes' .../has_many_through_association.rb:169:in `through_records_for' .../has_many_through_association.rb:180:in `block in delete_through_records' .../has_many_through_association.rb:179:in `each' .../has_many_through_association.rb:179:in `delete_through_records' .../has_many_through_association.rb:154:in `delete_records' .../has_many_through_association.rb:124:in `delete_or_nullify_all_records' .../collection_association.rb:214:in `delete_all' .../collection_proxy.rb:443:in `delete_all’ ar_test_scripts/ar_rails_test.rb:85:in `<main>'
89. .../activerecord/lib/active_record/associations/ through_association.rb:48:in `block in construct_join_attributes’
90. def construct_join_attributes(*records) ensure_mutable if source_reflection.association_primary_key(reflection.klass) == reflection.klass.primary_key join_attributes = { source_reflection.name => records } else join_attributes = { source_reflection.foreign_key => records.map { |record| record.send(source_reflection.association_primary_key( reflection.klass)) } } end if options[:source_type] join_attributes[source_reflection.foreign_type] = records.map { |record| record.class.base_class.name } [...]
91. CALLER $ cd railsconf_scripts/ $ open puts_caller.rb
92. ActiveRecord::Schema.define do create_table :projects do |t| t.string :name end end class Project < ActiveRecord::Base after_create :call_me def call_me puts "======== i am a callback ========" end end class BugTest < Minitest::Test def test_create project = Project.create!(name: "whatever") end end
93. create_table :projects do |t| t.string :name end end class Project < ActiveRecord::Base after_create :call_me def call_me puts caller puts "======== i am a callback ========" end end class BugTest < Minitest::Test def test_create project = Project.create!(name: "whatever") end end
94. CALLER $ bundle exec ruby puts_caller.rb
95. .../activesupport/lib/active_support/callbacks.rb:428:in `block in make_lambda' .../activesupport/lib/active_support/callbacks.rb:229:in `call' .../activesupport/lib/active_support/callbacks.rb:229:in `block in halting_and_conditional' .../activesupport/lib/active_support/callbacks.rb:502:in `call' .../activesupport/lib/active_support/callbacks.rb:502:in `block in call' .../activesupport/lib/active_support/callbacks.rb:502:in `each' .../activesupport/lib/active_support/callbacks.rb:502:in `call' .../activesupport/lib/active_support/callbacks.rb:90:in `run_callbacks' .../activerecord/lib/active_record/callbacks.rb:305:in `_create_record' .../activerecord/lib/active_record/timestamp.rb:57:in `_create_record' .../activerecord/lib/active_record/persistence.rb:506:in `create_or_update' .../activerecord/lib/active_record/callbacks.rb:301:in `block in create_or_update' .../activesupport/lib/active_support/callbacks.rb:86:in `run_callbacks' .../activerecord/lib/active_record/callbacks.rb:301:in `create_or_update' .../activerecord/lib/active_record/persistence.rb:151:in `save!' [...]
96. .../activesupport/lib/active_support/callbacks.rb: 428:in `block in make_lambda'
97. def make_lambda(filter) case filter when Symbol lambda { |target, _, &blk| target.send filter, &blk } when String l = eval "lambda { |value| #{filter} }" lambda { |target, value| target.instance_exec(value, &l) } when Conditionals::Value then filter when ::Proc if filter.arity > 1 return lambda { |target, _, &blk| raise ArgumentError unless block target.instance_exec(target, block, &filter) } end if filter.arity <= 0 lambda { |target, _| target.instance_exec(&filter) } else lambda { |target, _| target.instance_exec(target, &filter) } [...]
98. def test_reject_if_method_without_arguments Pirate.accepts_nested_attributes_for :ship, reject_if: :new_record? pirate = Pirate.new(catchphrase: "Stop wastin' me time") pirate.ship_attributes = { name: 'Black Pearl' } assert_no_difference('Ship.count') { pirate.save! } end
100. def test_reject_if_method_without_arguments Pirate.accepts_nested_attributes_for :ship, reject_if: :new_record? pirate = Pirate.new(catchphrase: "Stop wastin' me time") tp = TracePoint.new(:call) do |*args| p args end tp.enable pirate.ship_attributes = { name: 'Black Pearl' } tp.disable assert_no_difference('Ship.count') { pirate.save! } end
101. def test_reject_if_method_without_arguments Pirate.accepts_nested_attributes_for :ship, reject_if: :new_record? pirate = Pirate.new(catchphrase: "Stop wastin' me time") tp = TracePoint.new(:call) do |*args| p args end tp.enable pirate.ship_attributes = { name: 'Black Pearl' } tp.disable assert_no_difference('Ship.count') { pirate.save! } end
102. def test_reject_if_method_without_arguments Pirate.accepts_nested_attributes_for :ship, reject_if: :new_record? pirate = Pirate.new(catchphrase: "Stop wastin' me time") tp = TracePoint.new(:call) do |*args| p args end tp.enable pirate.ship_attributes = { name: 'Black Pearl' } tp.disable assert_no_difference('Ship.count') { pirate.save! } end
103. def test_reject_if_method_without_arguments Pirate.accepts_nested_attributes_for :ship, reject_if: :new_record? pirate = Pirate.new(catchphrase: "Stop wastin' me time") tp = TracePoint.new(:call) do |*args| p args end tp.enable pirate.ship_attributes = { name: 'Black Pearl' } tp.disable assert_no_difference('Ship.count') { pirate.save! } end
104. def test_reject_if_method_without_arguments Pirate.accepts_nested_attributes_for :ship, reject_if: :new_record? pirate = Pirate.new(catchphrase: "Stop wastin' me time") tp = TracePoint.new(:call) do |*args| p args end tp.enable pirate.ship_attributes = { name: 'Black Pearl' } tp.disable assert_no_difference('Ship.count') { pirate.save! } end
105. `ship_attributes='@.../activerecord/lib/active_record/nested_attributes.rb:347 `assign_nested_attributes_for_one_to_one_association'@.../activerecord/lib/active_record/ nested_attributes.rb:382 `nested_attributes_options'@.../activesupport/lib/active_support/core_ext/class/attribute.rb:106 `nested_attributes_options'@.../activesupport/lib/active_support/core_ext/class/attribute.rb:86 `with_indifferent_access'@.../activesupport/lib/active_support/core_ext/hash/indifferent_access.rb:8 `new_from_hash_copying_default'@.../activesupport/lib/active_support/hash_with_indifferent_access.rb:75 `initialize'@.../activesupport/lib/active_support/hash_with_indifferent_access.rb:58 `update'@.../activesupport/lib/active_support/hash_with_indifferent_access.rb:127 `convert_key'@.../activesupport/lib/active_support/hash_with_indifferent_access.rb:258 `convert_value'@.../activesupport/lib/active_support/hash_with_indifferent_access.rb:262 `ship'@.../activerecord/lib/active_record/associations/builder/association.rb:110 `association'@.../activerecord/lib/active_record/associations.rb:149 `association_instance_get’@.../activerecord/lib/active_record/associations.rb:189 `_reflect_on_association'@.../activerecord/lib/active_record/reflection.rb:109 `_reflections'@.../activesupport/lib/active_support/core_ext/class/attribute.rb:86 `association_class'@.../activerecord/lib/active_record/reflection.rb:435 `macro'@.../activerecord/lib/active_record/reflection.rb:588 `require'@.../activesupport/lib/active_support/dependencies.rb:272 `load_dependency'@.../activesupport/lib/active_support/dependencies.rb:236 `load?'@.../activesupport/lib/active_support/dependencies.rb:311 `mechanism'@.../activesupport/lib/active_support/core_ext/module/attribute_accessors.rb:60 `constant_watch_stack'@.../activesupport/lib/active_support/core_ext/module/attribute_accessors.rb:60 `watching?'@.../activesupport/lib/active_support/dependencies.rb:99 `delegate'@.../activesupport/lib/active_support/core_ext/module/delegation.rb:151 `include?'@/Users/eileen/.rbenv/versions/2.2.0/lib/ruby/2.2.0/set.rb:211 `initialize'@.../activerecord/lib/active_record/associations/association.rb:24 `check_validity!'@.../activerecord/lib/active_record/reflection.rb:331 `check_validity_of_inverse!’@.../activerecord/lib/active_record/reflection.rb:335 ...
106. `ship_attributes='@.../activerecord/lib/active_record/ nested_attributes.rb:347
107. def generate_association_writer(association_name, type) generated_association_methods.module_eval <<-eoruby, __FILE__, __LINE__ + 1 if method_defined?(:#{association_name}_attributes=) remove_method(:#{association_name}_attributes=) end def #{association_name}_attributes=(attributes) assign_nested_attributes_for_#{type} _association(:#{association_name}, attributes) end eoruby end
108. TRACE POINT $ cd railsconf_scripts/ $ open trace_point.rb
109. class User < ActiveRecord::Base has_one :avatar accepts_nested_attributes_for :avatar end class Avatar < ActiveRecord::Base belongs_to :user end class BugTest < Minitest::Test def test_trace_point user = User.new(name: "My Name") user.avatar_attributes = { name: "I am a file name" } user.save! end end
110. end class Avatar < ActiveRecord::Base belongs_to :user end class BugTest < Minitest::Test def test_trace_point user = User.new(name: "My Name") tp = TracePoint.new(:call) do |*args| p args end user.avatar_attributes = { name: "I am a file name" } user.save! end end
111. class Avatar < ActiveRecord::Base belongs_to :user end class BugTest < Minitest::Test def test_trace_point user = User.new(name: "My Name") tp = TracePoint.new(:call) do |*args| p args end tp.enable user.avatar_attributes = { name: "I am a file name" } tp.disable user.save! end end
112. TRACE POINT $ bundle exec ruby trace_point.rb
113. `avatar_attributes='@.../activerecord/lib/active_record/ nested_attributes.rb:347
114. ADVANCED GIT COMMANDS
115. GIT $ git add . $ git commit -m‘Commit message’ $ git checkout practicing-git
116. GIT $ git add upstream $ git bisect $ git reset --[soft|hard] $ git rebase -i $ git reflog
117. GIT REMOTES $ cd path/to/rails/ $ git remote add upstream https://github.com/rails/rails.git
118. GIT REMOTES $ cd path/to/rails/ $ git remote remove upstream $ git remote add upstream https://github.com/rails/rails.git
119. GIT REMOTES $ git pull —-rebase upstream master
120. GIT REMOTES $ git pull —-rebase upstream master $ git push origin master
121. GIT BISECT $ git bisect
122. GIT BISECT $ git bisect start
123. GIT BISECT $ git bisect bad $ git bisect good v4.2.rc3
125. Practice Git Bisect C1 C2 C3 C4 C5 C6 M3 M4 M0
126. AMENDING COMMITS $ git commit --amend
127. GIT RESET $ git reset --soft HEAD@{1}
128. GIT RESET $ git reset --soft HEAD~N
129. GIT RESET $ git reset HEAD
130. Git Reset M1 M2 M3 M4 M0 master HEAD Practice
131. GIT REBASE -I $ git rebase -i master
132. GIT
133. 1 pick e92e34f Refactor existing code 2 pick 80601e8 Oops add in missing code 3 pick 8d91f76 Remove extra piece I left behind 4 pick 933bd58 Fix bug reported in #9895 5 pick 99302ef Clean up changes 6 pick 5cc3c5a Fix spelling mistake in documentation 7 8 # Rebase 0131d99..5cc3c5a onto 0131d99 9 # 10 # Commands: 11 # p, pick = use commit 12 # r, reword = use commit, but edit the commit message 13 # e, edit = use commit, but stop for amending 14 # s, squash = use commit, but meld into previous commit 15 # f, fixup = like "squash", but discard this commit's log 16 # x, exec = run command (the rest of the line) using shell
134. 1 pick e92e34f Refactor existing code 2 pick 80601e8 Oops add in missing code 3 pick 8d91f76 Remove extra piece I left behind 4 pick 933bd58 Fix bug reported in #9895 5 pick 99302ef Clean up changes 6 pick 5cc3c5a Fix spelling mistake in documentation 7 8 # Rebase 0131d99..5cc3c5a onto 0131d99 9 # 10 # Commands: 11 # p, pick = use commit 12 # r, reword = use commit, but edit the commit message 13 # e, edit = use commit, but stop for amending 14 # s, squash = use commit, but meld into previous commit 15 # f, fixup = like "squash", but discard this commit's log 16 # x, exec = run command (the rest of the line) using shell
135. 1 reword e92e34f Refactor existing code 2 pick 80601e8 Oops add in missing code 3 pick 8d91f76 Remove extra piece I left behind 4 pick 933bd58 Fix bug reported in #9895 5 pick 99302ef Clean up changes 6 pick 5cc3c5a Fix spelling mistake in documentation 7 8 # Rebase 0131d99..5cc3c5a onto 0131d99 9 # 10 # Commands: 11 # p, pick = use commit 12 # r, reword = use commit, but edit the commit message 13 # e, edit = use commit, but stop for amending 14 # s, squash = use commit, but meld into previous commit 15 # f, fixup = like "squash", but discard this commit's log 16 # x, exec = run command (the rest of the line) using shell
136. 1 reword e92e34f Refactor existing code 2 pick 80601e8 Oops add in missing code 3 edit 8d91f76 Remove extra piece I left behind 4 pick 933bd58 Fix bug reported in #9895 5 pick 99302ef Clean up changes 6 pick 5cc3c5a Fix spelling mistake in documentation 7 8 # Rebase 0131d99..5cc3c5a onto 0131d99 9 # 10 # Commands: 11 # p, pick = use commit 12 # r, reword = use commit, but edit the commit message 13 # e, edit = use commit, but stop for amending 14 # s, squash = use commit, but meld into previous commit 15 # f, fixup = like "squash", but discard this commit's log 16 # x, exec = run command (the rest of the line) using shell
137. 1 reword e92e34f Refactor existing code 2 pick 80601e8 Oops add in missing code 3 edit 8d91f76 Remove extra piece I left behind 4 pick 933bd58 Fix bug reported in #9895 5 squash 99302ef Clean up changes 6 pick 5cc3c5a Fix spelling mistake in documentation 7 8 # Rebase 0131d99..5cc3c5a onto 0131d99 9 # 10 # Commands: 11 # p, pick = use commit 12 # r, reword = use commit, but edit the commit message 13 # e, edit = use commit, but stop for amending 14 # s, squash = use commit, but meld into previous commit 15 # f, fixup = like "squash", but discard this commit's log 16 # x, exec = run command (the rest of the line) using shell
138. 1 reword e92e34f Refactor existing code 2 fixup 80601e8 Oops add in missing code 3 edit 8d91f76 Remove extra piece I left behind 4 pick 933bd58 Fix bug reported in #9895 5 squash 99302ef Clean up changes 6 pick 5cc3c5a Fix spelling mistake in documentation 7 8 # Rebase 0131d99..5cc3c5a onto 0131d99 9 # 10 # Commands: 11 # p, pick = use commit 12 # r, reword = use commit, but edit the commit message 13 # e, edit = use commit, but stop for amending 14 # s, squash = use commit, but meld into previous commit 15 # f, fixup = like "squash", but discard this commit's log 16 # x, exec = run command (the rest of the line) using shell
139. 1 reword e92e34f Refactor existing code 2 fixup 80601e8 Oops add in missing code 3 edit 8d91f76 Remove extra piece I left behind 4 pick 933bd58 Fix bug reported in #9895 5 squash 99302ef Clean up changes 6 pick 5cc3c5a Fix spelling mistake in documentation 7 8 # Rebase 0131d99..5cc3c5a onto 0131d99 9 # 10 # Commands: 11 # p, pick = use commit 12 # r, reword = use commit, but edit the commit message 13 # e, edit = use commit, but stop for amending 14 # s, squash = use commit, but meld into previous commit 15 # f, fixup = like "squash", but discard this commit's log 16 # x, exec = run command (the rest of the line) using shell
140. Practice M1 M2 M3 M4 F1 F2 F1 F2 M0 Interactive Rebase
141. FORCE PUSH $ git push -f origin your-branch
142. GIT REFLOG $ git reflog
144. GIT REFLOG $ git reflog
145. 628c168 HEAD@{0}: rebase -i (finish): returning to refs/heads/your-branch 628c168 HEAD@{1}: rebase -i (start): checkout master 628c168 HEAD@{2}: reset: moving to 628c168 bc503a1 HEAD@{3}: rebase -i (finish): returning to refs/heads/your-branch bc503a1 HEAD@{4}: rebase -i (pick): Add Person model and migration 1ad2ff2 HEAD@{5}: rebase -i (pick): Improve README section on git reflog 026457d HEAD@{6}: rebase -i (start): checkout master 633f620 HEAD@{7}: rebase -i (finish): returning to refs/heads/your-branch 633f620 HEAD@{8}: rebase -i (pick): Improve README section on git reflog 19f41a7 HEAD@{9}: commit (amend): Add Person model and migration 50718b1 HEAD@{10}: rebase -i (edit): Add Person model and migration 026457d HEAD@{11}: rebase -i (reword): Update README with sections on rebase and c8c6000 HEAD@{12}: rebase -i (reword): Update README with sections on rebase and 628fbd2 HEAD@{13}: rebase -i (squash): Update README description section 455dab0 HEAD@{14}: rebase -i (fixup): # This is a combination of 2 commits. 4392779 HEAD@{15}: rebase -i (start): checkout master 628c168 HEAD@{16}: rebase -i (finish): returning to refs/heads/your-branch 628c168 HEAD@{17}: rebase -i (start): checkout master 628c168 HEAD@{18}: rebase -i (finish): returning to refs/heads/your-branch 628c168 HEAD@{19}: rebase -i (start): checkout master 628c168 HEAD@{20}: rebase: aborting 1f935f7 HEAD@{21}: rebase -i (edit): Add Person model and migration
146. GIT REFLOG $ git reset -—hard 628c168
147. 628168 628168 50718b bc503a1 C1 C2 C3 C4 C0 Git Reflog Practice
148. FINDING ISSUES TO WORK ON
149. WHAT TO WORK ON $ Test release candidates and that master branch
150. WHAT TO WORK ON % Test release candidates and that master branch $ Fix documentation & work on WIP Guides
151. WHAT TO WORK ON % Test release candidates and that master branch % Fix documentation & work on WIP Guides $ Focus on your strengths
152. WHAT TO WORK ON % Test release candidates and that master branch % Fix documentation & work on WIP Guides % Focus on your strengths $ Work on ActiveJob or WebConsole
153. WHAT TO WORK ON % Test release candidates and that master branch % Fix documentation & work on WIP Guides % Focus on your strengths % Work on ActiveJob or WebConsole $ Review open pull requests
154. WHAT TO WORK ON % Test release candidates and that master branch % Fix documentation & work on WIP Guides % Focus on your strengths % Work on ActiveJob or WebConsole % Review open pull requests $ Refactoring methods and tests
155. WHAT TO WORK ON % Test release candidates and that master branch % Fix documentation & work on WIP Guides % Focus on your strengths % Work on ActiveJob or WebConsole % Review open pull requests % Refactoring methods and tests $ Watch the issues tracker
156. WHAT WE COVERED % Getting set up % Guidelines for opening issues % Writing test scripts % Guidelines for opening pull requests % Git % Bisect, Interactive Rebase, Reflog % Traversing unfamiliar code % source_location, CTags, puts caller, TracePoint % Finding issues to work on
157. Thank You!
158. EILEEN M. UCHITELLE Programmer at Basecamp ! eileencodes.com " @eileencodes # @eileencodes Slides: speakerdeck.com/eileencodes