Git beyond commit - keep your history clean

Mergen Sie noch oder Rebasen Sie schon? In dieser Session schauen wir uns ein
paar Tricks mit git an, mit dem Ziel die git History sauber und lesbar zu halten.
Hier findet vieles Anwendung, was über das übliche Commiten und Pushen in der IDE hinausgeht. Themen wie Interactive Rebase, fixup, autosquash und das Splitten von Hunks finden hier unter anderem seinen Platz.
Je nach Lust und Laune sind auch Abstecher in andere Themen denkbar.

Transcript

1. Git - beyond commit
   keep your history clean
   Yannick Baron
   @yannick_baron
   Software Architecture Consultant
   

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2. "Git is easy"
   

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3. Clone the repository
   
   
   "Git is easy"
   

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4. Clone the repository
   
   
   Make changes
   
   
   "Git is easy"
   

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5. Clone the repository
   
   
   Make changes
   
   
   Mess things up
   
   
   "Git is easy"
   

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6. Clone the repository
   
   
   Make changes
   
   
   Mess things up
   
   
   Look at StackOver
   fl
   ow and copy an obscure command
   
   
   "Git is easy"
   

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7. Clone the repository
   
   
   Make changes
   
   
   Mess things up
   
   
   Look at StackOver
   fl
   ow and copy an obscure command
   
   
   Mess things up even more
   
   
   "Git is easy"
   

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8. Clone the repository
   
   
   Make changes
   
   
   Mess things up
   
   
   Look at StackOver
   fl
   ow and copy an obscure command
   
   
   Mess things up even more
   
   
   Delete folder
   
   
   "Git is easy"
   

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9. Clone the repository
   
   
   Make changes
   
   
   Mess things up
   
   
   Look at StackOver
   fl
   ow and copy an obscure command
   
   
   Mess things up even more
   
   
   Delete folder
   
   
   Clone the repository
   
   
   ...
   "Git is easy"
   

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10. https://stackover
    fl
    ow.com/questions?tab=Votes
    

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11. https://stackover
    fl
    ow.com/questions?tab=Votes
    

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12. The core of git
    

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13. • The git history is a graph, a tree to be precise
    
    
    • A node in that tree is the state of our
    fi
    les at a point in time
    
    
    • Most operations deal with how to navigate and manipulate that tree
    The git history
    

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14. Tree Interlude?
    

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15. • Understand the evolution of the project (history, communication)
    
    
    • Rollback to (or revert / redo) previous change
    
    
    • Find or compare to previously working code
    
    
    • Find which change introduced an error
    
    
    • Understand when development paths divert and see potential con
    fl
    ict
    
    
    • ...
    
    
    Uses of the git history
    

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16. • Understand the evolution of the project (history, communication)
    
    
    • Rollback to (or revert / redo) previous change
    
    
    • Find or compare to previously working code
    
    
    • Find which change introduced an error
    
    
    • Understand when development paths divert and see potential con
    fl
    ict
    
    
    • ...
    
    
    A clean history keeps things readable, traceable and makes integration of
    changes easier
    
    
    Uses of the git history
    

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17. Chaos vs Unity
    

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18. Embrace Rebase
    

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19. main
    feat feat
    main
    Simple Merge
    

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20. main
    feat feat
    main
    feat
    main
    Late Merge
    

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21. main
    feat
    main
    feat
    Control Merge
    main
    feat
    

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22. main
    feat
    main
    feat
    Control Merge
    feat
    main
    feat2
    

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23. main
    feat
    main
    feat
    main
    feat
    Rebase
    

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24. Why do control merges happen?
    

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25. But rebase is evil because force push is evil and loses data
    

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26. BuT rEbAsE iS eViL bEcAuSe fOrCe pUsH iS eViL aNd LoSeS dAtA
    

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27. But rebase is evil because force push is evil and loses data
    git push --force-with-lease git push --force-if-includes
    

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28. git add -p
    git commit --amend [--no-edit]
    git commit --fixup 

    git rebase -i --autosquash
    Tricks to keep the history clean
    

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29. Interactive Rebase
    

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30. •
    fi
    xup
    
    
    • squash
    
    
    • reordering
    
    
    • editing past commits
    
    
    • rewording
    
    
    • ...
    Interactive Rebase
    

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31. It's a wrap!
    • yannick.baron@thinktecture.com
    

    • https://www.thinktecture.com/thinktects/yannick-baron
    

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32. git bisect start
    git bisect bad
    git bisect good []
    Bonus: Bisect
    

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33. git worktree add []
    git worktree list
    git worktree remove
    Bonus: Worktrees
    

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