This cheat sheet provides a quick reference for essential Git commands, crucial for effective version control in software development. Mastering these commands will streamline your workflow and enhance collaboration.

User Identity and Configuration

Configure your Git environment to reflect your identity and preferences.

# To set your identity:
git config --global user.name <name>
git config --global user.email <email>

# To set your editor:
git config --global core.editor <editor>

# To enable color:
git config --global color.ui true

Staging and Committing Changes

Learn how to stage changes and create meaningful commits.

# To stage all changes for commit:
git add --all

# To commit staged changes:
git commit -m <message>

# To edit previous commit message:
git commit --amend

# Git commit in the past
git commit --date="`date --date='2 day ago'`"
git commit --date="Jun 13 18:30:25 IST 2015"
# more recent versions of Git also support --date="2 days ago" directly

# To change the date of an existing commit:
git filter-branch --env-filter \
    'if [ $GIT_COMMIT = 119f9ecf58069b265ab22f1f97d2b648faf932e0 ]
     then
         export GIT_AUTHOR_DATE="Fri Jan 2 21:38:53 2009 -0800"
         export GIT_COMMITTER_DATE="Sat May 19 01:01:01 2007 -0700"
     fi'

Managing Stashes

Temporarily save changes that are not ready for a commit.

# To stash changes locally, this will keep the changes in a separate changelist
# called stash and the working directory is cleaned. You can apply changes
# from the stash anytime
git stash

# To stash changes with a message:
git stash push -m <message>

# To list all the stashed changes:
git stash list

# To apply the most recent change and remove the stash from the stash list:
git stash pop

# To apply any stash from the list of stashes. This does not remove the stash
# from the stash list
git stash apply stash@{6}

Undoing and Resetting Changes

Revert unwanted changes and reset your working directory.

# To remove staged and working directory changes:
git reset --hard

# To go 2 commits back:
git reset --hard HEAD~2

# Checkout the fb branch, and rebase from <remote>
git reset --hard <remote>/<branch>

# To revert first/initial commit on a branch:
# Running git reset --hard HEAD~1 will give error:
# fatal: ambiguous argument 'HEAD~1': unknown revision or path not in the working tree.
git update-ref -d HEAD

# To remove untracked files:
git clean -f -d

# To remove untracked and ignored files:
git clean -f -d -x

Branching and Merging

Work with branches to manage different lines of development.

# Tags: Tag a commit
git tag -a <tag> <commit> -m "<commit message>"

# Tags: To push a tag to remote:
git push origin <tagname>

# Tags: To delete a tag <tagname> on remote
git push --delete origin <tagname>

# Tags: To delete a tag locally
git tag -d <tagname>

# Branches: To delete the branch <branch>:
git branch -D <branch>

# Branches: To delete a local <branch>:
git branch -d <branch>

# Branches: To delete a remote branch <branch>:
git push --delete origin <branch>

# Branches: To delete all branches on remote that are already merged:
git branch --merged | egrep -v "(^*|main|dev)" | xargs git branch -d

# Branches: To make an exisiting branch track a remote branch:
git branch -u upstream/foo

# To checkout a new branch from a different starting point:
git checkout -b master upstream/master

# To remove all stale branches (ones that have been deleted on remote): So if
# you have a lot of useless branches, delete them on Github and then run this:
git remote prune origin

# To prune all remotes at once:
git remote prune $(git remote | tr '\n' ' ')

Remote Operations and Synchronization

Interact with remote repositories to share and update code.

# To push to the tracked master branch:
git push origin master

# To push to a specified repository:
git push git@github.com:<username>/<repo>.git

# To force a push:
git push -f

# To sync a fork with the master repo:
git remote add upstream git@github.com:<username>/<repo>.git # Set a new repo
git remote -v                                                # Confirm new remote repo
git fetch upstream                                           # Get branches
git branch -va                                               # List local - remote branches
git checkout master                                          # Checkout local master branch
git checkout -b new_branch                                   # Create and checkout a new branch
git merge upstream/master                                    # Merge remote into local repo

# To pull changes while overwriting any local commits:
git fetch --all
git reset --hard origin/master

# To pull down a remote branch, but rebase any locally differing commits onto
# the top of the incoming commits:
git pull <remote> <branch> --rebase

Viewing History and Differences

Inspect commit history and track changes between versions.

# To see who commited which line in a file:
git blame <file>

# To show what a commit did.
git show 83fb499
# Shows the file as it appeared at 83fb499.
git show 83fb499:path/fo/file.ext
# Check difference between branches
git diff branch_1 branch_2
# Show all the commits
git log
# Show the changes from last commit
git status

# To view the commit history of a set of files:
git log --pretty=email --patch-with-stat --reverse --full-index -- Admin\*.py > Sripts.patch

# To view commits that will be pushed:
git log @{u}..

# To view changes that are new on a feature branch:
git log -p feature --not master
git diff master...feature

# To perform an interactive rebase for the prior 7 commits:
git rebase -i @~7

# To diff files WITHOUT considering them a part of git:
# This can be used to diff files that are not in a git repo!
git diff --no-index path/to/file/A path/to/file/B

# Revisions can also be identified with :/text
# So, this will show the first commit that has "cool" in their message body
git show :/cool

# To undo parts of last commit in a specific file:
git checkout -p HEAD^ -- /path/to/file

# To revert a commit and keep the history of the reverted change as a separate revert commit:
git revert <commit SHA>

# To pick a commit from a branch to current branch. This is different than
# merge as this just applies a single commit from a branch to current branch:
git cherry-pick <commit SHA1>

Advanced Operations and Submodules

Explore more advanced Git functionalities.

# To import commits from another repo:
git --git-dir=../some_other_repo/.git format-patch -k -1 --stdout <commit SHA> | git am -3 -k

# To update all submodules:
git submodule update --init --recursive

# To perform a shallow clone to only get latest commits:
# (helps save data when cloning large repos)
git clone --depth 1 <remote-url>

# To unshallow a clone:
git pull --unshallow

# To create a bare branch (one that has no commits on it):
git checkout --orphan branch_name

Signing Commits and Tags

Secure your commits and tags using GPG keys.

# Change author of a commit:
git commit --amend --author="Author Name <email@address.com>"

# The GPG key used for signing your commits
git config --global user.signingkey 0A46826A

# Sign new tags:
git tag -s v1.5 -m 'my signed 1.5 tag'

# Sign a commit:
git commit -a -S -m 'Signed commit'

# check any signatures it finds and list them in its output:
git log --pretty="format:%h %G? %aN %s"

# Defined the key to use for signing commits:
git config user.signingkey [KEYID]

# Set signing of commits globally:
git config --global commit.gpgsign true

Listing Files

View untracked files in your repository.

# To list unstracked files:
git ls-files --others --exclude-standard

For more in-depth information, refer to the official Git documentation and explore resources like Stack Overflow Git questions.