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Git Cheat-Sheet

A lot of this info was collected from the following sources as I used them myself to learn Git.

I was using git version 2.16.2.windows.1 in the Bash shell while documenting and testing these commands.

First Time Configuration

After installing Git on a new system, there are a few things that should be setup first.

For further configuration options, see the Git documentation.

Contact Info for Commits

git config --global user.name "First Last"
git config --global user.email "email@domain.com"

Handling Line Endings

# For Windows
git config --global core.autocrlf true
git config --global core.safecrlf true
# For Mac/Unix
git config --global core.autocrlf input
git config --global core.safecrlf true

Pretty Log Alias

More helpful aliases are demonstrated here.

This log command will give nice and pretty output:

git log --pretty=format:"%h %ad | %s%d [%an]" --graph --date=short

It can be configured in to a global alias like so:

git config --global alias.hist "log --pretty=format:'%h %ad | %s%d [%an]' --graph --date=short"

So now it's simply enough to do:

git hist
# or for all branches
git hist --all

VSCode as Editor and Diff Tool

More info here about Git integration with Visual Studio Code.

Set Visual Studio Code as the default Git editor, and configure it to wait for the editor to close before continuing:

git config --global core.editor "code --wait"

Now it's possible to edit the Git config in Visual Studio Code like so:

git config --global -e

Leveraging the above, add the following to .gitconfig:

[diff]
    tool = default-difftool
[difftool "default-difftool"]
    cmd = code --wait --diff $LOCAL $REMOTE

Review Git Configuration

# show all configuration settings
git config -l
# show global settings only
git config --global -l
# show system settings only
git config --system -l
# show repo settings only (must be in repo folder)
git config --local -l

Create and Clone Repos

A repo is created with git init, and cloned with git clone.

Create a repo in the current folder:

git init

Create a repo in the folder MyRepo(folder will be created if it doesn't exist):

git init MyRepo

From the parent folder, it's possible to clone a repo with:

git clone <origin> <dest>
# ex:
git clone MyRepo cloned_MyRepo

NOTE: A cloned repo will have a single master branch and remote branches tracked from the origin repo.

Bare Repos

Doing git init or git clone commands with the –bare switch will make a repo without a working directory, only Git data. A bare repo is intended for sharing (fetch/push/pull) only.

It's common for bare repos to have the suffix .git.

# create a new bare repo in current folder
git init --bare
# create a new bare repo in folder MyRepo.git
git init --bare MyRepo.git
# clone repo MyRepo into a bare repo MyRepo.git
git clone --bare MyRepo MyRepo.git

Multiple Repos

Syncing

Commits are pulled down from a remote repo via git fetch, however this doesn't automatically merge them in to the local branches.

# ex:
git fetch
# review status
git hist --all

However, merging remote fetched commits is the same as any other commits. This will merge all the commits from origin/master in to the currently checked out branch:

git merge origin/master

It's possible to effectively perform git fetch and git merge in a single command via git pull.

# fetch and merge origin/master in to current branch
git pull

Sending changes upstream to a remote repo is done via git push.

# push to <remoterepo> local <branch>
git push <remoterepo> <branch>
# ex:
git push origin master
# push everything
git push --all

If, as mentioned in managing remote repos, local branches are already configured to track remote branches, it shouldn't be necessary to specify any parameters. Simply running git push should be enough.

Tracking Branches

When a repo is cloned, the only local branch is master, and while the other remote branches are tracked, git pull and git push are only setup between the local and remote master branches. This can be confirmed by reviewing the remote configuration.

# check configured remote repos
git remote
# show details for a configured remote repo
git remote show <repo>
# ex:
git remote show origin

It is possible to create a local branch that tracks commits from a remote branch:

# create a new localbranch to track remotebranch
git branch --track <localbranch> <remotebranch>
# ex:
git branch --track dev1 origin/dev1

It is also possible to modify an existing local branch and set it to track commits from a remote branch:

# for currently checked out branch
git branch -u <remotebranch>
# ex:
git branch -u origin/dev1
# for NOT currently checked out branch
git branch -u <remotebranch> <localbranch>
# ex:
git branch -u origin/dev1 dev1

NOTE: After using git branch -u the local branch will display as fast-forwardable via git remote show origin. To clear this up, simply force a git push:

# push all refs
git push --all

Managing Remote Repos

# add a remote repo
git remote add <reponame> <repopath>
# ex:
git remote add origin ../folder
# remove remote repo
git remote rm <reponame>
# ex:
git remote rm origin

With git push -u it's possible accomplish the same things as git branch -u, the latter being more specific in how to link branches.

# configure branchname to track remote branchname on reponame
git push -u <reponame> <localbranch>
# ex:
git push -u origin master
git push -u origin dev1
# alternatively, this will do above for all branches
git push -u --all

When a repo is cloned, remote HEAD tracking is configured automatically. When setting up remote repos manually it's possible to do this with git remote set-head.

# set reponame/HEAD as master
git remote set-head <reponame> -a
# ex:
git remote set-head origin -a
# remove reponame/HEAD as master
git remote set-head <reponame> -d
# ex:
git remote set-head origin -d

In some cases it may be desired to disable git push and effectively setup a pull only repo. There is no official disable switch, but it's possible to provide a bogus URL that will generate an error.

# set the remoterepo push url
git remote set-url --push <remoterepo> <url>
# ex:
git remote set-url --push origin DISABLE

To track certain remote branches use git remote set-branches. Using the –add switch will append the current configuration, otherwise it will be replaced.

# track only <remoterepo> <remotebranch>
git remote set-branches <remoterepo> <remotebranch>
# ex:
git remote set-branches origin master
# whoops, also want to track dev1 branch
git remote set-branches --add origin dev1

Stage, Confirm, Commit, and Tag

Note: Before the initial commit occurs on a new repo, the master branch doesn't exist yet, and many commands will throw errors.

Stage files:

# a single file
git add file.txt
# multiple via wildcard
git add *.txt
# all via shell wildcard
# - will ignore what shell ignores, like .folders
git add *
# all via git wildcard
# - will pull in everything that isn't in .gitignore
git add .

Confirm repo status:

git status

Commit changes:

# commit and launch default editor to provide comment
git commit
# commit and provide comment in-line
git commit -m "Commit comment"

To correct a mistake in the last commit:

  • Make the necessary changes
  • Stage the necessary files
  • Perform a new commit with the –amend switch
git commit --amend -m "Commit comment"

Tag commits for easier management:

# tag the current commit with a friendly name
git tag <name>
# ex:
git tag v1
# tag the previous commit using '^' notation
git checkout v1^
git tag v0
git checkout v1
# remove tag
git tag -d v1

Undo Changes

Unstaged changes can be rolled back via git checkout.

# checkout a single file
git checkout file.txt
# checkout all files
git checkout .

This is not an undo, but instead of checking out files, it's possible to checkout a commit via the first 7 digits of the hash (from git hist if the alias is defined), or tags:

git checkout <hash>
# ex:
git checkout 9b2c81a

To return to the latest commit do:

git checkout <branch>
# ex:
git checkout master

Staged changes can be rolled back via git reset.

# unstage all currently staged changes
git reset
# unstage a particular file
git reset HEAD <file>
# ex:
git reset HEAD file.txt

NOTE: The working directory still has modified and unstaged files, use git checkout to replace them with committed version:

git checkout .
# or, for a single single file
git checkout file.txt

Commits can be canceled (but not removed) via git revert. Cancel commits by targeting their hash, or other identifiers.

This will cancel wherever HEAD is, which is usually the last commit:

git revert HEAD

Commits can be removed from history via git reset.

To revert the working directory to a specified commit, and remove all later commits from history:

git reset --hard <hash>
# ex:
git reset --hard e54ff04

NOTE: If removed commits had tags, those tags need to be removed or the commits will remain in history. This can be done after git reset:

git tag -d BadVersion

Moving Content

Content can be moved inside the repo via git mv, this is the best option when moving a single file, although more files just mean repeating the command for them.

# files and/or folders can be moved like this
git mv <source> <dest>
# ex:
git mv file.txt folder\file.txt
git mv folder1 folder2
# it's better to use 'git mv' instead of native file system
# to avoid more steps:
mv file.txt lib
git add folder/file.txt
git rm file.txt

If using the file system to move content around, especially serious restructuring, it's a better idea to use git add -A.

# update the entire worktree
git add -A
# update current folder and down
git add -A .
# update a specific folder
git add -A MyFolder

Branches

Branches are managed via git branch, switched via git checkout, and merged via git merge.

Create, List, Checkout, and Delete

# list branches
git branch
# create a new branch
git branch <name>
# ex:
git branch dev1
# list local branches
git branch
# list all branches
git branch -a
# switch working directory to branch dev1
git checkout dev1
# it's possible to create a new branch and checkout in one command
git checkout -b dev2
# to delete a branch (can't be checked out)
git branch -d dev1

Merging

# merge <branch> in to the currently checked out branch
git merge <branch>
# ex: # this brings all the changes from dev1 in to master
git checkout master
git merge dev1

Rebasing

Branches can be rebased with git rebase. Rebasing merges the branch histories in to a single thread, effectively performing a merge and then flattening the commit tree.

# rebase the currently checked out branch in to <branch>
git rebase <branch>
# ex: # this flattens the dev1 history in to master
git checkout dev1
git rebase master

NOTE: Rebasing can get tricky in some scenarios and cause issues, check the documentation for further details:

git rebase --help

Ignoring Content

It's possible to tell Git to ignore files and/or folders by using a .gitignore file.

See the following for more details and examples:

.gitignore
# matching is done on the whole path string, so
# this will ignore everything regardless of depth
*
# whatever exceptions are made, will only work in
# the current folder, unless recursion is allowed with
!*/
# this will whitelist at the top level
!*.ps1
# this will whitelist everywhere
!**/*.xml
# lines are processed in order, so it's possible
# to undo everything above with
!*

PowerShell Visual Studio Code Template

This is my baseline template for starting a PowerShell project in Visual Studio Code. It's effectively a white-list.

.gitignore
# ignore everything eveywhere
*
 
# allow folder recursion
!*/
 
# allow .gitignore at top level
!.gitignore
 
# whitelist these file types everywhere
!**/*.ps1
!**/*.psm1
!**/*.psd1
!**/*.xml
 
# regardless of above, ignore '.vscode' folder everywhere
**\.vscode/

Here is a template generated by gitignore.io for PowerShell, Visual Studio Code, and Windows.

.gitignore
# Created by https://www.gitignore.io/api/windows,powershell,visualstudiocode
 
### PowerShell ###
# Exclude packaged modules
*.zip
 
# Exclude .NET assemblies from source
*.dll
 
### VisualStudioCode ###
.vscode/*
!.vscode/settings.json
!.vscode/tasks.json
!.vscode/launch.json
!.vscode/extensions.json
.history
 
### Windows ###
# Windows thumbnail cache files
Thumbs.db
ehthumbs.db
ehthumbs_vista.db
 
# Folder config file
Desktop.ini
 
# Recycle Bin used on file shares
$RECYCLE.BIN/
 
# Windows Installer files
*.cab
*.msi
*.msm
*.msp
 
# Windows shortcuts
*.lnk
 
# End of https://www.gitignore.io/api/windows,powershell,visualstudiocode
git.1525896047.txt.gz · Last modified: 2018/05/09 16:00 by thekojukinator