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---

Nice stuff

• Manual Page
• D3 visual
• oshitgit

• 101

• Git has 3 levels of configuration:
  • SYSTEM: configurations for multiple users
  • GLOBAL: configurations used for one user all repo on one host
  • LOCAL: configuration for one repo

#list the configuration
git config --list 

#edit global configuration 
git config –e  --global

# get/add the user name
git config user.name
git config --global user.name "NAME"

• Primitive objects:
  • commit — object which contains the reference to another tree object
  • tree — object which contains references to other blobs or subtrees.
  • blob — object used for storing the contents of a single file.

    git add => BLOB
    git commit ==> COMMIT + TREE
    

• HEAD = pointer to the last commit on the branch
• git pull == git fetch + git merge
• git checkout -b = git branch + git checkout

Configure Git

$ git config --global user.name <YOUR NAME>
$ git config --global user.email <YOUR MAIL>

#disable SSL verification if you encounter SSL certificate problem: self signed certificate
$ git config --global http.sslVerify false

# use other ssh key
git -c core.sshCommand="ssh -i ~/.ssh/<PRIVATE_KEY>" clone git@github.com:dejanu/sretoolkit.git

# update ~/.ssh/config

Host github.com
    Hostname github.com
    PreferredAuthentications publickey
    IdentityFile ~/.ssh/<private_key>

---

Commands

• checkout and reset are generally used for making local or private ‘undos’, they’ll modify the history of a repo and can cause conflicts when pushing to remote
• revert is considered a safer operation for ‘public undos’ as it creates new history which can be shared remotely and doesn’t overwrite history remote

# view/add remote
git remote -v
git remote add origin remote_repository_URL
git remote set-url origin git://new.url.  //change the url repo
git remote remove origin


#  shorthand for git checkout -b [branch] [remotename]/[branch]
git checkout --track origin/remote_branch
git fetch <remote> <rbranch>:<lbranch> 
git checkout <lbranch>

# delete local/remote branch
git branch -D local_branch
git push --delete origin remote_branch

# clean working directory interactive mode
git clean -i

# UNDO changes in working directory a.k.a I've deleted a file and did not commit
git checkout -f <FILE>
git reset HEAD <filename>

# UNDO (unstage) changes in staging area 
git restore --staged <file>

# Reset current HEAD to the specified state (MIXED the default one)
git-reset

# UNDO last commit and PRESERVE changes
git reset --soft HEAD^ == git reset --soft HEAD^1
git reset --soft HEAD~1 

# much wow (undo 2 commits) 
git reset --head X 2 == git reset HEAD^^ 

# UNDO last commit and REMOVE changes, combine both git reset and git checkout in a single command
git reset --hard HEAD~1 


# create a new commit which usually has the inverse effect of the commit being reverted.
git revert HEAD --no-edit | git revert HASH

# rename local branch, push it and delete the old branch
git branch -m <oldname> <newname>
git push origin -u <newname>
git push origin --delete <oldname>

---

FunStuff

GitHooks article

# before counting unmerger/stale branches
git remote update origin --prune

# delete all branches merged into develop from local and remote
git branch -r --merged develop | grep -vE "develop|master|release" | xargs -n 1 git branch -d
git branch -r --merged master | grep -vE "develop|master|release" | awk -F'/' '{print $2}'|xargs -n 1 git push --delete origin

# diff MERGED vs UNMERGED branches
git branch -r --merged | grep -v HEAD | xargs -L1 git --no-pager log --pretty=tformat:'%Cgreen%d%Creset | %h | %an | %Cblue%ar%Creset' -1 | column -t -s '|'
git branch -r --no-merged | grep -v HEAD | xargs -L1 git --no-pager log --pretty=tformat:'%Cgreen%d%Creset | %h | %an | %Cblue%ar%Creset' -1 | column -t -s '|'

# loop through each unmerged branch and tell you (a) when the last commit was made, and (b) how many commits it contains which are not merged to ‘origin/master’
for b in $(git branch --remote --no-merged); do

    echo $b;

    git show $b --pretty="format:  Last commit: %cd" | head -n 1;

    echo -n "  Commits from 'master': ";

    git log --oneline $(git merge-base $b origin/master)..$b | wc -l;

    echo;

done

# pull all remote branches
for remote in `git branch -r`; do git branch --track ${remote#origin/} $remote; done

# check the parent branch

git show-branch | grep '*' | grep -v \"$(git rev-parse --abbrev-ref HEAD)\" | head -n1 | sed 's/.*\\[\\(.*\\)\\].*/\\1/' | sed 's/[\\^~].*//' #
git log --color --graph --pretty=format:'%Cred%h%Creset -%C(yellow)%d%Creset %s %Cgreen(%cr) %C(bold blue)<%an>%Creset' --abbrev-commit
git log --first-parent

---

Inspection

# check commits 
git log --author="Jon"
git log --graph --oneline --all

# check only the commit msg aka subject
git log --pretty=format:"%s"

# examine the contents of a file
git blame <FILE>
gitk --follow <FILE>

# modify last commit
git commit --amend 

# list remote branches
git branch -va

# check remote unmerged branches
git branch -r --no-merged

# check commit
git show COMMIT_HASH

---

                    ___ _____
                   /\ (_)    \
                  /  \      (_,
                 _)  _\   _    \
                /   (_)\_( )____\
                \_     /    _  _/
                  ) /\/  _ (o)(
                  \ \_) (o)   /
                   \/________/         @dejanualex