Git Reference

git

git add . [-A]
	- Recursively add all modified files to staging area
	  -A - Include removed files

git blame
  - Show last modigified timestamp / author for each line of a file

git branch [-a] [-r] [-m] [-d] [-D] [<branch-name>]
  - Lists local branches, give name to create branch
  - Flags:git 
    -a - Include remote branches
    -r - Remote branches
    -m - Rename current branch (with branch name)
    -d - Delete branch (with branch name), prevents from deleting unmerged changes
    -D - Delete branch (with branch name)

git checkout [-b] <branch> [<remote/branch>]
	- Switch the current working directory to the specified branch
	  -b - Create local branch
	  <remote/branch> - Specify remote branch to create local branch from (with -b)

git checkout <commit> [<file>]
  - Update all working files in directory (or specified file only) to commit
  - Use HEAD as commit to get back to current version
  
git checkout <file>
  - Rollback uncommited changes in file

git clean -f [<path>]
	- Remove untracked files, optionally limit to path
	
git clean -df
  - Remote untracked files and directories
  
git clean -xf
  - Remove untracked files and ignored files (as specified by .gitignore)

git commit -m "<message>"
	- Commit staged files with commit message
	
git commit --amend [-m "<message>"|--no-edit]
  - Amend and replace commit with staged changes, optionally update message

git config --global user.email "<email>"
git config --global user.name "<name>"
  - Set email and name for commits
  
git config --global diff.tool vi
git config --global merge.tool vi
git config --global --add difftool.prompt false
  - Set diff tool and prevent difftool prompt
  
git diff
	- check diff of all unstaged changes

git fetch <remote> [<branch>]
	- Fetch all branches from remote, or optionally specify branch

git init
	- Initialize a new git repository in current directory

git init --bare
  - Initialize a new git repository in current directory, with no central repo (for git servers)
  
git log [<since>..<until>] [<file>] [-n <limit>] [-p]
  - Show commit history
    <since>..<until> - to show hitory between commits or since branching
      e.g. git log master feature
    <file> - limit to commits including file
    -n <limit> - optional limit
    -p - full patch info
  - Flags:
    --oneline - Reduce to single line per commit
    --stat - Add file changes with line counts
    --author="<pattern>" - Show commits by author (string / regex)
    --grep="<pattern>" - Show commits by searching message (string /
    regex)
    --graph - Display simple graph

git ls-remote [<repo>]
  - Display remote repository references

git merge [--no-ff] <[remote/]branch>
	- Merge branches into current branch, no-ff to always merge commit

git merge -X rename-threshold=<percent> branch
	- Merge branch into current working directory allowing for file renaming
	
git merge --abort
	- rollback merge in case of conflicts between branches (to last commit)

git mergetool
	- Launch mergetool for merge conflict resolution

git pull <remote> [<branch>] [--rebase]
	- Fetch and merge in a single action, optionally specify branch, optionally specify rebase rather than merge
	
git push <remote> <branch>|-all
	- Push changes to remote repo

git push <remote> --tags
	- Push tags to remote repo
	
git push <remote> :<branch>
     - Delete a remote branch

git rebase [-i] <base>
  - Rebase current branch with specified reference (merges history)
  - For combining multiple commits into one
  - Flags:
    -i - interactive

git reflog [--relative-date]
  - Show HEAD history, optionally show relative date

git remote [-v]
  - Displays remotes, -v for all uni-directional remote repos deails (fetch / push for each)

git remote rename <old-name> <new-name>
  - Rename remote
  
git remote add <name> <url>
	- Add a remote repository for current project

git remote show
	- Show all current remote repos for current working directory

git remote rm <name>
	- Remove a remote branch from local

git reset [<file>]
  - Unstage all or unspecified file
  
git reset [--hard] <commit>
	- Unstage changes, use HEAD / '' for current snapshot
	  - Flags:
	    --hard - Reset files in working directory to commit

git restore <file>
  - Return file to current commit
  
git restore --staged <file>
  - Unstage file
  
git revert [-m1] <commit>
  - Revert a commit, use HEAD to revert last commit
    -m1 - Revert merge commit (to mainline parent)
    
git stash [-u]
  - Stash (local store without commit) current changes on branch
  - Add -u to include untracked (new) files
  
git stash pop
  - Bring back stashed changes
  
-----
HEAD is latest commit, can use HEAD~n to specify a number of commits ago
-----

rm .git/index
  - Undo staged files (when there is no HEAD yet)
  
git rev-list --ancestry-path $(git merge-base <common-ancestor-branch> <branch>)..<branch> | tail -1
  - Find first commit on branch since fork

git --no-pager show -s --format='%an <%ae>' <commit_id>
  - Show author of a commit

WORKFLOWS

Pull Requests - Fork, Clone, Branch, Push, Pull Request
  1. Fork the repo (if not done already) - In GitHub UI
  2. Clone the fork locally (if not done already) - git clone <repo>
  3. Setup the upstream locally, i.e. the original repo (if not done already) - git remote add --track <branch> upstream <repo> && git fetch upstream
  4. Create a branch locally - git checkout -b <branch>
  5. Make changes
  6. Commit changes and push to fork - git add . && git commit -m "<message>" && git push origin <branch>
  7. Raise a pull request in the original repo - in GitHub UI
  
Post Pull Request Merge
  1. Cleanup the branch on the fork - git checkout <branch(main/master)> && git branch -d <branch> && git push origin :<branch>
  2. Pull latest upstream (which now includes the branch) - git pull upstream <branch(main/master)>
  3. Push latest to fork (so we work on latest) - git push origin <branch(main/master)>

Remove committed files which are subsequently added to .gitignore
  1. git rm -r --cached .
  2. git add .
  3. git commit -m "<message>"
  4. etc


SUPER COMMANDS!

PRETTY PROJET HISTORY (credit www.kerrybuckley.org)
git log --pretty=%h | tail -r | while read sha ; do if [[ -z $(git rev-parse --verify $sha^2 2> /dev/null) ]] ; then echo '----' ; git show --summary $sha | tail -n+5 | egrep -v '^ (?:create|delete) mode' ; git --no-pager diff --color -U999 $sha~ $sha | awk '/diff --git/ { sub("^a/", "", $3) ; print "===" $3 } /diff --git/, /@@/ { next } { print }' ; fi ; done | ansifilter -H | sed 's/^----$/<hr \>>/;s/===\(.*\)/<h2>\1<\/h2>/' > history.html

SETUP GLOBAL GIT IGNORE
touch ~/.gitignore
git config --global core.excludesFile ~/.gitignore
//Update ignores in file
//Remove files added to gitignore since commit
git rm -r --cached .
git add .
git commit -m ".gitignore fix"