This is the deck part of a 1,5 hours workshop delivered at AtlasCamp 2015. Follow along or just sit back and enjoy a live, hands on tutorial on the power routines of experienced git users. We'll explore with real world examples how to do an interactive rebase - and why would you want to do one in the first place, how to solve conflicts without any merge tools, stashing tricks, the power of less known merge strategies and much more.

1. Master the art and practice of DVCS
NICOLA PAOLUCCI • DEVELOPER INSTIGATOR • ATLASSIAN • @DURDN
Power routines of experienced Git users

2. REMOVE BINARIES
Follow along, solve real world daily
version control situations
CONFLICT RESOLUTION
MERGE STRATEGIES
INTERACTIVE COMMITS
AMEND AND REBASE

3. ADVENTURE AWAITS
Follow along the adventure
This session won’t be interactive but you can
follow along and try to beat me to tasks by
cloning this repository
git clone
git@bitbucket.org:nicolapaolucci/starwars-summary.git

4. About the sample project

5. ADVENTURE AWAITS
House keeping [1]
Get a nice prompt: Liquid prompt is awesome
http://bit.do/liquid-prompt

6. ADVENTURE AWAITS
House keeping [2]
If you are creating a new repository, start with an
empty commit and tag it
git commit -m"[empty] Initial commit" --allow-empty
git tag initial <first-sha-1> -m"Tag initial commit"

7. ADVENTURE AWAITS
House keeping [3]
To speed up the typing I have created a few
aliases that we will re-use throughout
ls = log --decorate --oneline
ll = log --decorate --numstat
http://bit.do/gitconfig

8. Common and not so common
un-doings and re-doings
Amending and Re-basing

9. Credit: Emma Jane Hogbin Westby
@emmajanehw

10. Credit: Emma Jane Hogbin Westby
@emmajanehw

11. THEORY
Always think of these
Work directory
Which tree does my command affect?
Index or
Staging area
Local repository
(.git) Remotes

12. UNDOINGS
Memorise or alias this to amend quickly
Amend the last commit with everything I have
here uncommitted and new
caa = commit -a --amend -C HEAD

13. THEORY
Default git reset is of type mixed…
Work directory
Which tree does my command affect?
Index or
Staging area
Local repository
(.git)
HEAD
master
git reset HEAD~
HEAD
HEAD
HEAD

14. changes
THEORY
Default git reset is a mixed reset…
Work directory
Which tree does my command affect?
Index or
Staging area
Local repository
(.git)
HEAD
master
git reset HEAD~
HEAD
HEAD

15. Ancestry references
You can specify commits via their ancestry.
The more common examples are
HEAD^ = the parent of commit HEAD
HEAD~2 = traverses the first
parent 2 times, finds
the grand parent

16. Now let’s change a
commit in the past

17. What is a rebase?
It’s a way to replay commits, one
by one, on top of a branch
master
feature

18. What is an
--interactive rebase?
Helps you clean up your private branches
before publishing them
reword
fixup
pick
squash
edit
exec

19. For complex history
cleanup use
git filter-branch or BFG

20. UNDOINGS
BFG Repo-Cleaner is a nice option
http://bit.do/bfg

21. Let’s learn to solve conflicts
Believe me, it can be done without tears and sweat.

22. CONFLICT RESOLUTION
A word on terminology
Current checked
out branch
--ours
What do ours and theirs mean when solving conflicts?
Commit coming in
(i.e. via merge)
--theirs

23. CONFLICT RESOLUTION
Basics for easy conflict resolution
The common commands are:
$ git checkout --ours/--theirs <file>
Check back out our own/their own version of the file
$ git add <file>
Add the change to the index will resolve the conflict

24. CONFLICT RESOLUTION
Aliases for easy conflict resolution
Add these to [alias] in .gitconfig:
ours = "!f() {
}; f"
git checkout --ours $@ && git add $@;

25. Embrace useful merge strategies
Merging the right way can go a long way…

26. What is a merge?
Merge
commit
master
feature
merges keep the context of the
feature’s commits
feature
m
aster

27. tree f362c42032aff677c1a09c3f070454df5b411239
parent 49a906f5722ad446a131778cea52e3fda331b706
parent bd1174cd0f30fe9be9efdd41dcd56256340f230e
author Marcus Bertrand <mbertrand@atlassian.com>
1409002123 -0700
committer Marcus Bertrand <mbertrand@atlassian.com>
1409002123 -0700
Merge branch 'foo/mybranch'
.git/objects/36/80d8c8fd182f97cb0e75045e2fed5c7b7613ed
commit
Anatomy of a merge

28. Let’s talk about merge strategies!
git has breadth of choice on how to
merge changes!
recursiveresolve octopus
subtreeours yours?

29. merge strategy: ours
master
feature
Records a merge but skips incoming changes
IGNORE!

30. strategy --ours is useful
to promote recent
branches to master

31. feature
What is a fast-forward merge?
master
It will just shift the HEAD tag
feature
m
aster

32. What is a fast-forward merge?
master
It will just shift the HEAD tag
feature
m
aster

33. Octopus merge is
nice for staging
servers.

34. UNDOINGS
Octopus Merge can be very useful
http://bit.do/git-octopus

35. UNDOINGS
Octopus Merge can be very useful

36. Interactive add (and commit)
Splitting commits semantically in flight!

37. Stage this hunk [y,n,q,a,d,/,s,e,?]? ?
y - stage this hunk
n - do not stage this hunk
q - quit; do not stage this hunk or any of the remaining ones
a - stage this hunk and all later hunks in the file
d - do not stage this hunk or any later hunks in the file
g - select a hunk to go to
/ - search for a hunk matching the given regex
j - leave this hunk undecided, see next undecided hunk
J - leave this hunk undecided, see next hunk
k - leave this hunk undecided, see previous undecided hunk
K - leave this hunk undecided, see previous hunk
s - split the current hunk into smaller hunks
e - manually edit the current hunk
? - print help

38. Switch context at will
Git stash power techniques

39. git stash is awesome
It’s a way to temporarily store your
unsaved work on a stack of patches
stash@{0}
stash@{1}
stash@{2}
stash@{3}
git stash save

41. Thank you!
NICOLA PAOLUCCI • DEVELOPER INSTIGATOR • ATLASSIAN • @DURDN
Twitter: @durdn