brew install git
.bashrc or .bash_profileに追加
source /usr/local/etc/bash_completion.d/git-prompt.sh
source /usr/local/etc/bash_completion.d/git-completion.bash
下記も追加
GIT_PS1_SHOWDIRTYSTATE=true
export PS1='\h\[\033[00m\]:\W\[\033[31m\]$(__git_ps1 [%s])\[\033[00m\]\$ '
反映
source ~/.bashrc
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