Title: Do you really understand git? First Name: Guillermo Last Name: Polito Abstract: In this session we will revise some git basics that are needed to become a git expert. - Git as a graph: what are commits, branches and tags and how do they relate? - Branching and merging. Conflict!? What does git tell me there? - Remotes and upstream, are they the same? - Github pull requests and branching. Come with your questions. We will try to find the answers in git's documentation ;). Bio: Guille Polito is research engineer at the CRIStAL laboratory in the university of Lille, working in tight relation with the RMoD team. Guille's main research interests are techniques to develop modular systems and new development tools. Guille participates in the Pharo community since 2010. His most noticeable contributions in the past months are in the Pharo bootstrap process, Pharo stream management, Iceberg and OSSubprocess.

1. Do you really understand
Git?
本当に分かる？
by Guille Polito
@GuillePolito

2. Tuesday 16:30
Friday 10:00

3. Why ?
• Visibility
• Manage more than only code
• Lower entry barrier into the community
• Lots of exisGng tools
• Good branch support, good diff
• …

4. Where would you place
yourself?

5. Where would you place
yourself?

6. Where would you place
yourself?

7. Where would you place
yourself?

8. A Test
$
How do you **clean** your working copy?

9. A Test
$ git reset
How do you **clean** your working copy?
This will reset your index

10. A Test
$ git reset --hard
How do you **clean** your working copy?
Well, yes, but not quite.
This will reset your working copy.
But not remove untracked files.

11. A Test
How do you **clean** your working copy?
$ git reset --hard
$ git clean -fd

12. is not easy
• New terminology:
index, HEAD, pull, push, fetch
• False friends: merge, commit
• Command-line oriented
• DocumentaGon is someGmes ambiguous, someGmes
incomplete

13. is not easy (2)
• MulGple workflows are a two-edged machete
There is no One, single ring to rule them all
• People mix workflows, philosophy and technical
soluGons (try reading some blogs…)
• Graphical tools are too general or too specific

14. +
Just makes it harder
• Image-based persistence
• Files vs packages
• MonGcello adds
more false friends!
Tuesday 16:30

15. An easy way to
1. It’s a graph!
2. It’s a two-stage database!

16. as a Graph
b8bfed7
7ba52e5
35ac17f
a4153b1
b01aba4 feature_branch
master_branch
v1.0 <tag>
HEAD
parent
reference
Labels:
!me moves in this direc!on

17. commit
37adf4e master HEAD
parent
reference
Labels:
!me moves in this direc!on

18. commit
37adf4e
master HEAD0c0e5ff
parent
reference
Labels:
!me moves in this direc!on

19. branch
parent
reference
Labels:
37adf4e
master0c0e5ff
development
HEAD
!me moves in this direc!on

20. commit (2)
parent
reference
Labels:37adf4e
master
0c0e5ffdevelopment
dc4a3e7 HEAD
!me moves in this direc!on

21. checkout
37adf4e
master
0c0e5ff
development
b894b84 dc4a3e7
HEAD
parent
reference
Labels:
!me moves in this direc!on

22. checkout
37adf4e
master
0c0e5ff
development
b894b84 dc4a3e7
HEAD
parent
reference
Labels:
!me moves in this direc!on

23. DETACHED
HEAD?
parent
reference
Labels:37adf4e
master
HEAD
0c0e5ff
v1.0.0
!me moves in this direc!on

24. merge
parent
reference
Labels:
37adf4e
master
0c0e5ff
development
b894b84 dc4a3e7
HEAD
!me moves in this direc!on

25. merge
parent
reference
Labels:
37adf4e
master
0c0e5ff
development
b894b84 dc4a3e7
2dae910 HEAD
!me moves in this direc!on

26. merge
fast-forward
parent
reference
Labels:
37adf4e
0c0e5ff
development dc4a3e7
master HEAD
!me moves in this direc!on

27. merge
fast-forward
parent
reference
Labels:
37adf4e
0c0e5ff
development dc4a3e7 master HEAD
!me moves in this direc!on

28. as a 2-stage
Database
Working Copy Index Repository
What you see Where
commits are
A “hidden”
staging area
(sort of)
Remote
repositories

29. add
Working Copy Index Repository

30. commit
Working Copy Index Repository

31. checkout
Working Copy Index Repository

32. fetch
Working Copy Index Repository

33. push
Working Copy Index Repository

34. pull?
$ git fetch
$ git merge

35. +
Tuesday 16:30
=

36. The 4 Gps of the Iceberg

37. Show the “Good” Path

38. Warn about DestrucGon

39. Guide out of the Darkness

40. Use a Clear Language
workingCopy commitWithMessage: ‘message’.
aRepository head.
aBranch pull.

41. Tuesday 16:30
Friday 10:00
And if you
want more
Or this cool website:
hjps://learngitbranching.js.org/

42. Working Copy Index Repository
add commit
fetch
push
checkout/merge
b8bfed7
7ba52e5
35ac17f
a4153b1
b01aba4 feature_branch
master_branch
v1.0 <tag>
HEAD
parent
reference
Labels: