Git walkthrough outlines the basics of using Git including source control, configuration, viewing history, undoing changes, tagging, branching, and hosting on platforms like GitHub. It discusses initializing and cloning repositories, adding, committing, and pushing changes. Specific commands are demonstrated for status checking, diffing, resetting, merging, and more. New features introduced in Git 2.0 such as improved defaults for push and add are also reviewed.

1. Git walkthrough
@modsaid

2. Outline
● Source Control
● Git Basics
● Configuration
● Viewing history
● Undoing
● Aliases
● Tagging
● Branching
● Remotes
● Bare repos
● Hosting: Github, bitbucket, ...
● Git 2.0+

3. Version
Control
System

4. Centralized
Version
Control
System

5. Distributed
Version
Control
System

6. Git Basics
● Local Repo ( .git )
● Working directory

7. Git Basics - The 3 States

8. Git Basics
● git init
● git status
● git add
● git commit
● git reset
● git clone
● git mv
● git rm
● git blame
● git push
● git pull

9. Git Basics - committing
# Initializing a new repo
$ git init .
# Staging
$ git add .
$ git add -A
# committing
$ git commit -m “initial commit”

10. Git Basics - committing
$ git status
# diff (working vs staged)
$ git diff
# diff (staged vs committed)
$ git diff -s
# Stage and commit in one shot
$ git commit -a -m “direct staging and commit”

11. Git Configuration
● System
● User
● repo
/etc/gitconfig
~/.gitconfig or ~/.config/git/config
.git/config

12. Git Configuration
git config --system
git config --global
git config --local

13. Git Configuration
$ git config --global user.name "John Doe"
$ git config --global user.email johndoe@example.
com
$ git config --global core.editor emacs
$ git config --list
$ git config user.name

14. Viewing History
$ git log
$ git log -p -2
$ git log --stat
$ git log --grep adding
$ git log --since=2.weeks
$ git log --Sfunction_name
$ git log --pretty=oneline
$ git log --pretty=format:"%h - %an, %ar : %s"

16. Viewing History
$ git log --pretty=format:"%ad %an : %s " --
date=short
$ git log --pretty=oneline --since=”2012-12-20”
--until=”2013-01-01” -5
$ git log --pretty=oneline | wc -l #no of commits
$ git log --pretty=format:%cd --date=short |
uniq | wc -l #no of working days

17. Viewing History
$ git shortlog
$ git shortlog -s | wc -l #no of devs
$ git shortlog -se # list of devs
#no of coding days
$ git log --pretty=format:”%ad” --date=short |
uniq | wc -l

18. Viewing History - mapping names
$ git shortlog -se | grep -i john
6 John Doe <john.doe@espace.com.eg>
10 John-Doe <john.doe@espace.com.eg>
4 John.Doe <john.doe@espace.com.eg>
$ vim .mailmap
name1 name2 name3 mail@example.com
name4 mail@example.com
$ git shortlog -se > .mailmap

19. Undoing
git commit --amend
# Changing commit message
$ git commit --amend -m “better commit message”
# Adding forgotten file
$ git commit -m 'initial commit'
$ git add forgotten_file
$ git commit --amend

20. Undoing
#Unstaging
$ git add .
$ git status
$ git reset HEAD benchmarks.rb
#dropping local commits <DANGER>
git reset --hard HEAD~3

21. Git Aliases
$ git config --global alias.co checkout
$ git config --global alias.ci commit
$ git config --global alias.st status
$ git config alias.showdevs 'shortlog -s'
$ git config --global alias.unstage 'reset HEAD
--'

22. Tagging
● Lightweight: pointer to specific commit
$ git tag before-optimization
● Annotated: full objects, checksummed,
contains tagger info, suitable for
releases
$ git tag -a v1.4 -m 'my version 1.4'

23. Tagging
#Tagging later
$ git tag -a v1.2 9fceb02
$ git show v1.2
$ git push origin v1.5
$ git push origin --tags

24. Branching
$ git branch #List current branches
$ git branch newone # create a new branch newone
$ git checkout newone # switch to newone branch
# create branch and switch in one step
$ git checkout -b newtwo

25. Branching
# Committing on master

26. Branching
$ git branch testing

27. Branching

28. Branching
$ git checkout testing

29. Branching
$ git commit -a -m “some change”

30. Branching
$ git checkout master

31. Branching
$ git commit -a -m “master commit”

32. Branching - Merging
$ git merge testing
# in case of conflicts (failed auto merge)
$ git mergetool

33. Branching - Merging
fast-forward
git merge feature
no fast-forward
git merge --no-ff feature

34. Remotes
# Listing remotes
$ git remote
$ git remote -v
# Adding a remote
$ git remote add [shortname] [url]
$ git remote show origin

35. Remotes
# Fetching updates
$ git fetch [remote-name]
$ git remote rename pb paul
$ git remote rm paul

36. Bare Repos
● git repo with no working directory
● The git server side
$ git init --bare .
# Cloning (backup)
$ git clone --bare git@github.com:modsaid/git-demo2.git
# Restoring
$ git push --mirror git@bitbucket.org:modsaid/git-demo2.git

37. Hosting: github, bitbucket
● Github: the most popular, free public repos
● Bitbucket: free private with limited
collaborators
● A lot others

38. Github
● Exploring repos
● Pull Requests
● Contribution to repos:
○ Fork
○ Fix/Add
○ Send pull request
https://help.github.com/articles/fork-a-repo/

39. Latest git
The latest git release today is 2.3.3

40. Installing the latest git (2.3)
$ sudo add-apt-repository ppa:git-core/ppa
$ sudo apt-get update
$ sudo apt-get install git

41. What’s new in Git 2.0
“From the point of view of end-users who are totally new to
Git, this release will give them the defaults that are vastly
improved compared to the older versions, but at the same
time, for existing users, this release is designed to be as
low-impact as possible as long as they have been following
recent releases along.”
● Better Defaults

42. what’s new? git push
pre git 2.0
● Default: matching
starting git 2.0
● Default: simple
git config push.default
● ( nothing | current | upstream | simple | matching )

43. what’s new? git add -u
pre git 2.0
● stage files in working directory
starting git 2.0
● stage files in the Repo Directory

44. what’s new? git diff -q
pre git 2.0
● valid option
starting git 2.0
● Removed
Do not display deleted files during git diff

45. what’s new?
● https://raw.githubusercontent.com/git/git/master/Documentation/RelNotes/2.0.0.txt
● https://raw.githubusercontent.com/git/git/master/Documentation/RelNotes/2.1.0.txt
● https://raw.githubusercontent.com/git/git/master/Documentation/RelNotes/2.2.0.txt
● https://raw.githubusercontent.com/git/git/master/Documentation/RelNotes/2.3.0.txt

46. Resources
● Pro Git, Second Edition
By: Scott Chacon; Ben Straub
Publisher: Apress
Pub. Date: November 19, 2014
● git help COMMAND (man pages)
● Git Recipes by BasayelSaid

47. Thank You