Yet Another Git Cheatsheet
Tags: github, git
Published: 2019-12-07 16:41:11

###### *image source https://acodez.in/gitlab-vs-github-vs-bitbucket/*

### What is Git
> Git  is  the  free  and  open  source  distributed  version  control  system that is widely used by the world today. It helps in tracking changes in source code during software development. It is designed for coordinating work among programmers, but it can be used to track changes in any set of files. Its goals include speed, data integrity, and support for distributed, non-linear workflows.

### What is Version Control
> Version control keeps track of every modification to the code. If a mistake is made, developers can compare earlier versions of the code to help fix the mistake while minimizing disruption to all team members.

### How to use this cheatsheet
> If ever comes the time where you'll need to refer to any of the Git commands or if you are unsure of the syntax to use, feel free to pop by this cheatsheet and hit 'Cmd + f' for Mac users or 'Ctl + f' for Windows users to look for any relevant details.

### Other useful  resource
> [Start a new Git Repo from scratch](https://kbroman.org/github_tutorial/pages/init.html)
> [Advance Git CheatSheet](chrome-extension://oemmndcbldboiebfnladdacbdfmadadm/https://www.atlassian.com/dam/jcr:8132028b-024f-4b6b-953e-e68fcce0c5fa/atlassian-git-cheatsheet.pdf)
> [Git](https://git-scm.com/)
> [OhShitGit](https://ohshitgit.com/)
> [Git: Cheat Sheet (advanced)](https://dev.to/maxpou/git-cheat-sheet-advanced-3a17)

###### * Take Note: *
> This cheatsheet if subjected to futher updates whenever there are new commands that I want to take note of so that I can revisit again in the future.

---
### 1. Git Basics
Create empty Git repo in specified directory. Run with no arguments to initialize the current directory as a git repository.
```sh
git init <directory>
```
Clone repo located at `<repo>` onto local machine. Original repo can be located on the local filesystem or on a remote machine via HTTP or SSH.
```sh
git clone <repo>
```
Stage all changes in `<directory>` for the next commit. Replace `<directory>` with a 
`<file>` to change a specific file.
```sh
git add <directory>   # to add specific dir
git add .             # to add all that are not staged for the next commit
```
It's a good practice to commit unstaged snapshots. Commit the staged snapshot, but instead of launching a text editor, use `<message>` as the commit message.
```sh
git commit -m "<message>"
```
Replace the last commit with the staged changes and last commit combined. Use with nothing staged to edit the last commit’s message.
```sh
git commit --amend
```
List which files are staged, unstaged, and untracked.
```sh
git status
```
---
### 2. Logging
Display the entire commit history using the default format. For customization see additional options.
```sh
git log
```
Limit number of commits by `<limit>`. E.g. git log -5 will limit to 5 commits.
```sh
git log -<limit>
```
Condense each commit to a single line.
```sh
git log --oneline
```
Display full diff of each commit.
```sh
git log -p
```
Include which files were altered and the relative number of lines that were added or deleted from each of them.
```sh
git log -stat
```
Search commits for a particular author
```sh
git log --author="<pattern>"
```
Search for commits with a commit message that matches `<pattern>`.
```sh
git log --grep="<pattern>"
```
Show commits that occur between `<since>` and `<until>`. Args can be a commit ID, branch name, HEAD, or any other kind of revision reference.
```sh
git log <since>..<until>
```
Only display commits that have the specified file.
```sh
git log -- <file>
```
`--graph` flag draws a text based graph of commits on left side of commit msgs. `--decorate` adds names of branches or tags of commits shown.
```sh
git log --graph --decorate
```
---
### 3. Checking Differences
Show unstaged changes between your index and working directory.
```sh
git diff
```
Show difference between working directory and last commit.
```sh
git diff HEAD
```
Show difference between staged changes and last commit.
```sh
git diff --cached
```
---
### 4. Undoing Changes or Rewriting History
Create new commit that undoes all of the changes made in `<commit>`, then apply it to the current branch.
```sh
git revert <commit>
```
Reset staging area to match most recent commit, but leave the working directory unchanged.
```sh
git reset
```
Remove `<file>` from the staging area, but leave the working directory unchanged. This unstages a file without overwriting any changes.
```sh
git reset <file>
```
Reset staging area and working directory to match most recent commit and overwrites all changes in the working directory
```sh
git reset --hard
```
Move the current branch tip backward to `<commit>`, reset the staging area to match, but leave the working directory alone
```sh
git reset <commit>
```
Resets both the staging area AND working directory to match. Deletes uncommitted changes, and all commits after `<commit>`
```sh
git reset --hard <commit>
```
Shows which files would be removed from working directory. Use the -f flag in place of the -n flag to execute the clean.
```sh
git clean -n
```
Rebase the current branch onto `<base>`. `<base>` can be a commit ID, a branch name, a tag, or a relative reference to HEAD.
> Git merge is always a forward moving change record. Alternatively, rebase has powerful history rewriting features.
```sh
git rebase <base>
```
Interactively rebase current branch onto <base>. Launches editor to entercommands for how each commit will be transferred to the new base
```sh
git rebase -i <base>
```
Show a log of changes to the local repository’s HEAD. Add `--relative-date` flag to show date info or `--all` to show all refs.
```sh
git reflog
```
---
### 4. Git branches
List all of the branches in your repo. Add a `<branch>` argument to create a new branch with the name `<branch>`
```sh
git branch
```
Create and check out a new branch named `<branch>`. Drop the -b flag to checkout an existing branch.
```sh
got checkout -b <branch>
```
Merge `<branch>` into the current branch.
```sh
git merge <branch>
```
---
### 5. Remote Repositories
Create a new connection to a remote repo. After adding a remote, you can use `<name>` as a shortcut for `<url>` in other commands.
```sh
git remote add <name> <url>
```
Fetches a specific `<branch>`, from the repo. Leave off `<branch>` to fetch all remote refs.
```sh
git fetch <remote> <branch>
```
Fetch the specified remote’s copy of current branch and immediately merge it into the local copy.
```sh
git pull <remote>
```
Fetch the remote’s copy of current branch and rebases it into the local copy. Uses git rebase instead of merge to integrate the branches.
> The rebase command integrates changes from one branch into another. It is an alternative to the better known "merge" command. 
> Most visibly, rebase differs from merge by rewriting the commit history in order to produce a straight, linear succession of commits.
```sh
git pull --rebase <remote>
```
Push the branch to `<remote>`, along with necessary commits and objects. Creates named branch in the remote repo if it doesn’t exist.
```sh
git push <remote> <branch>
```
Forces the  git push  even if it results in a non-fast-forward merge. Do not use the `--force` flag unless you’re absolutely sure you know what you’re doing.
```sh
git push <remote> --force
```
Push all of your local branches to the specified remote
```sh
git push <remote> --all
```
Tags aren’t automatically pushed when you push a branch or use the `--all` flag. The `--tags` flag sends all of your local tags to the remote repo.
```sh
git push <remote> --tags
```
---
### 6. Git Configurations
Define author name to be used for all commits in current repo. Developerss commonly use `--global` flag to set config options for current user.
```sh
git config user.name <name>
```
Define the author name to be used for all commits by the current user
```sh
git config --global user.name <name>
```
Define the author email to be used for all commits by the current user.
```sh
git config --global user.email <email>
```
Create shortcut for a Git command.
```sh
git config --global alias. <alias-name> <git-command>
```
Set text editor used by commands for all users on the machine. `<editor>` arg should be the command that launches the desired editor (e.g. vi).
```sh
git config --system core.editor <editor>
```
Open the global configuration file in a text editor for manual editing.
```sh
git confg --global --edit
```
---
### 7. Temporarily store modified, tracked files in order to change branches
Save modified and staged changes.
```sh
git stash
```
list stack-order of stashed file changes.
```sh
git stash list
```
Write working from top of stash stack.
```sh
git stash pop
```
Discard the changes from top of stash stack
```sh
git stash drop
```
---
### 8. Other Useful Git Commands
Show Git remote URL, or if your are not connected to a network that can reach the remote repo.
```sh
git config --get remote.origin.url
```
Show Git remote URL if you are on a network that can reach the remote repo where the origin resides.
```sh
git remote show origin
```
Git push existing repo to a new and different remote repo server.
```sh
# Create a new repo at github.
# Copy the new Git repo URL.
git remote rename origin upstream
git remote add origin <NEW_GIT_REPO_URL>
git push origin master
```