On Linux

On most distributions, git completion script is installed into /etc/bash_completion.d/ (or /usr/share/bash-completion/completions/git) when you install git, no need to go to github. You just need to use it - add this line to your .bashrc:

source /etc/bash_completion.d/git
# or
source /usr/share/bash-completion/completions/git

In some versions of Ubuntu, git autocomplete may be broken by default, reinstalling by running this command should fix it:

sudo apt-get install git-core bash-completion

On Mac

You can install git completion using Homebrew or MacPorts.

Homebrew

if $BASH_VERSION > 4: brew install bash-completion@2 (updated version) Pay special care which version of bash you have as MacOS default ships with 3.2.57(1)-release.

add to .bash_profile:

  [[ -r "/usr/local/etc/profile.d/bash_completion.sh" ]] && . "/usr/local/etc/profile.d/bash_completion.sh"

For older versions of bash: brew install bash-completion

add to .bash_profile:

[ -f /usr/local/etc/bash_completion ] && . /usr/local/etc/bash_completion

MacPorts

sudo port install git +bash_completion

then add this to your .bash_profile:

if [ -f /usr/share/bash-completion/bash_completion ]; then
    . /usr/share/bash-completion/bash_completion
fi

more info in this guide: Install Bash git completion

Note that in all cases you need to create a new shell (open a new terminal tab/window) for changes to take effect.

i had same issue, followed below steps:

curl  -o ~/.git-completion.bash

then add the following lines to your .bash_profile (generally under your home folder)

if [ -f ~/.git-completion.bash ]; then
  . ~/.git-completion.bash
fi

source :

Most of the instructions you see will tell you to download

and source that in your bash startup script like .bashrc.

But there is a problem with that, because it is referencing the master branch, which is the latest version of git-completion.bash. The problem is that sometimes it will break because it is not compatible with the version of git you've installed.

In fact, right now that will break because the master branch's git-completion.bash has new features that requires git v2.18, which none of the package managers and installers have updated to yet. You'll get an error unknown option: --list-cmds=list-mainporcelain,others,nohelpers,alias,list-complete,config

So the safest solution is to reference the version/tag that matches the git you've installed. For example:

Note that it has a v2.17. in the URL instead of master. And then, of course, make sure to source that in the bash startup script.

Ubuntu 14.10

Install git-core and bash-completion

sudo apt-get install -y git-core bash-completion

• For current session usage

  source /usr/share/bash-completion/completions/git
  

• To have it always on for all sessions

  echo "source /usr/share/bash-completion/completions/git" >> ~/.bashrc
  

See

You just need to source the completion script

Just do this in your ~/.bashrc:

source /usr/share/bash-completion/completions/git

Other answers are telling you to install bash-completion, you don't need to do that, but if you do, then there's no need to source the completion directly. You do one or the other, not both.

A more generic solution is querying the system location as recommended by the bash-completion project:

source "$(pkg-config --variable=completionsdir bash-completion)"/git

on my ubuntu there is a file installed here:

source /etc/bash_completion.d/git-prompt

you can follow the links into the /usr/lib/git-core folder. You can find there an instruction, how to set up PS1 or use __git_ps1

May be helpful for someone:--

After downloading the .git-completion.bash from the following link,

curl  -o ~/.git-completion.bash

and trying to use __git_ps1 function, I was getting error as--

 -bash: __git_ps1: command not found

Apparently we need to download scripts separately from master to make this command work, as __git_ps1 is defined in git-prompt.sh . So similar to downloading .git-completion.bash , get the git-prompt.sh:

curl -L  > ~/.bash_git

and then add the following in your .bash_profile

source ~/.bash_git
if [ -f ~/.git-completion.bash ]; then
  . ~/.git-completion.bash
export PS1='\W$(__git_ps1 "[%s]")>'
fi

source ~/.bash.git will execute the downloaded file and

export PS1='\W$(__git_ps1 "[%s]") command will append the checkout out branch name after the current working directory(if its a git repository).

So it will look like:-

dir_Name[branch_name] where dir_Name is the working directory name and branch_name will be the name of the branch you are currently working on.

Please note -- __git_ps1 is case sensitive.

macOS via Xcode Developer Tools

Of all the answers currently posted for macOS, this is only mentioned in a very brief comment by jmt...

If you already have the Xcode developer tools installed, then you shouldn't need to download anything new.

Instead, you just need to locate the already-existing git-completion.bash file and source it in your .bashrc. Check the following directories:

• /Applications/
• /Library/Developer/CommandLineTools/usr/share/git-core

Failing that, git itself might be able to help you out. When I run git config as follows, git reports a setting which comes from a gitconfig file located in the same directory as my git-completion.bash:

$ git config --show-origin --list
...
file:/Applications/    credential.helper=osxkeychain
...

or you can always brute-force search your machine and grab some coffee:

$ find / -type f -name git-completion.bash 2>/dev/null

Thus, I have the following insertion for my ~/.bashrc:

# Git shell completion and prompt string on macOS
_git_dir="/Applications/"
if [ -f "${_git_dir}/git-completion.bash" ]; then
    source "${_git_dir}/git-completion.bash"
fi
if [ -f "${_git_dir}/git-prompt.sh" ]; then
    source "${_git_dir}/git-prompt.sh"
fi
unset _git_dir

Note that this sources the git prompt-string script as well, since it resides in the same directory.

(Tested in macOS Catalina)

Arch Linux

Source /usr/share/git/completion/git-completion.bash in one of the bash startup files.

For example:

# ~/.bashrc

source /usr/share/git/completion/git-completion.bash

You may be able to find the script in other locations like /usr/share/bash-completion/completions/git but these scripts did not work for me.

Windows

How it works for me finally on Windows 10 command line (cmd):

• Install Clink
• Copy git-autocomplete.lua file into C:\Users\<username>\AppData\local\clink directory
• Restart Windows

Ubuntu

There is a beautiful answer here. Worked for me on Ubuntu 16.04