Effective Git

Transcript

1. If that doesn't fix it, git.txt contains the phone number

   of a friend of mine who understands git. Just wait through a few minutes of 'It's really pretty simple, just think of branches as...' and eventually you'll learn the commands that will fix everything.

2. EFFECTIVE GIT Michael Cordell

3. GIT: THE BASICS git is a distributed version control system

4. EDITING class Startup def increase_roi step_one step_two “????” profit! end

   end

5. STAGING ƭ startup.rb git add startup.rb Index

6. COMMITTING ƭ startup.rb Index git commit -m “Add the startup!”

7. ƭ ƭ ƭ ƭ

8. BRANCHING master git checkout -b feature feature

9. BRANCHING master feature git commit

10. BRANCHING master feature git commit

11. BRANCHING feature git checkout master master

12. BRANCHING feature git commit master

13. BRANCHING feature git merge feature master

14. WHY

15. Code Editor || IDE VCS Build Tools

16. Build Tools Editor/IDE Now VCS

17. Since git deals with history, git’s effectiveness as a tool

    is directly related to how it has been used in the past

18. GUIDING PRINCIPLES

19. Short, focused commits

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22. Short, focused commits

23. Meaningful commit messages

24. KEY GIT PROPERTIES

25. GIT HISTORY IS A GRAPH

26. git history is a directed acyclic graph

27. git history is a directed acyclic graph

28. git history is a directed acyclic graph X

29. Commits in git are immutable

30. Commits in git are immutable Attempting to change: • Message

    • Content (file objects) • Parent commit results in the creation of a new commit

31. In contrast, references in git are cheap and movable

32. IN PRACTICE

33. IN PRACTICE: CONFIGURATION Learn to use aliases for faster git

    commands In your shell config: In your ~/.gitconfig $ git status $ g s
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36. IN PRACTICE: STAGING git add -p not git add .

    Use editor plugins for easy staging by hunk or line
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39. IN PRACTICE: COMMITTING First line is capitalized, short (50 chars

    or less) summary Second line is blank Rest of commit message should explain why and other useful information about the change See Tim Pope’s blog post on commit messages

40. RE-WRITING HISTORY

41. AMENDING git commit --amend alias cam = git commit --amend

    --no-edit

42. REBASING master feature git merge feature

43. REBASING master git reset --hard HEAD~1 feature

44. REBASING master feature git checkout feature

45. REBASING master feature git rebase master

46. REBASING master git rebase master

47. REBASING git rebase master master

48. REBASING git rebase master master feature

49. master feature master feature f87cb a98fc cc47a 18dd2 744ee 8ca01

    8ca01 ac871 ac871

50. master f87cb a98fc cc47a 18dd2 744ee 8ca01 feature ac871 git

    checkout feature

51. f87cb cc47a 18dd2 8ca01 ac871 master a98fc 744ee feature git

    reset --hard f87cb

52. INTERACTIVE REBASE git rebase -i master

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54. rebase conflicts are the same as merge conflicts, resolve and

    git rebase -i master

55. git diff against the pre-rebase commit if you are worried

    about conflict mistakes

56. USING THE HISTORY

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59. IN PRACTICE: BLAMING Use git blame to find why a

    line changed -w flag to ignore whitespace changes
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63. GIT BISECT FOR BUG HUNTING master

64. GIT BISECT FOR BUG HUNTING master

65. GIT BISECT FOR BUG HUNTING master git bisect start

66. GIT BISECT FOR BUG HUNTING master git bisect good HEAD~7

67. GIT BISECT FOR BUG HUNTING master git bisect bad master

68. GIT BISECT FOR BUG HUNTING master git bisect

69. GIT BISECT FOR BUG HUNTING master git bisect bad

70. GIT BISECT FOR BUG HUNTING master

71. GIT BISECT FOR BUG HUNTING master git bisect good

72. GIT BISECT FOR BUG HUNTING master

73. GIT BISECT FOR BUG HUNTING master git bisect bad

74. MOVING/COMPARING CODE git checkout diff reset REF { }

75. MOVING/COMPARING CODE git checkout diff reset REF { } switch

    to that reference

76. MOVING/COMPARING CODE git checkout diff reset REF { } compare

    current against that reference

77. MOVING/COMPARING CODE git checkout diff reset REF { } get

    the files at that reference

78. MOVING/COMPARING CODE git checkout diff reset { }REF

79. MOVING/COMPARING CODE git checkout diff reset REF -- FILES {

    }

80. FIXING “MISTAKES”

81. In git, nothing added is ever “lost”

82. FIXING A BAD MERGE Usually this is as simple as

    backing the commit out by reseting one commit back git reset --hard HEAD~1 If you want to just fix a single badly merged file checkout the file you want git checkout GOOD_REF -- file

83. REFLOG FOR EVERYTHING ELSE git reflog keeps a reference of

    reach change in the HEAD reference (checkouts, rebase, cherry-picks, etc.) find the commit from before the change you want to fix and reset/checkout against it reflog expires after 90 days, but you can turn this off and have it never expire
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87. git checkout diff reset b73c8c7 { }

88. LOST A STASH? git fsck can be used to find

    files that were at one time staged or perhaps stashed and dropped

89. REMOTES

90. REMOTES master

91. REMOTES master origin/master git pull

92. REMOTES master origin/master git pull

93. REMOTES master origin/master git pull

94. REMOTES master origin/master git pull

95. If you are going to force push prefer: git push

    --force-with-lease

96. End

97. FURTHER READING Think Like a Git Hartl’s Free eBook Cook’s

    Git from the inside out