High Sierra clean solution with colors !
No downloads. No brew. No Xcode
Just add it to your ~/.bashrc or ~/.bash_profile
export CLICOLOR=1
[ -f /Library/Developer/CommandLineTools/usr/share/git-core/git-prompt.sh ] && . /Library/Developer/CommandLineTools/usr/share/git-core/git-prompt.sh
export GIT_PS1_SHOWCOLORHINTS=1
export GIT_PS1_SHOWDIRTYSTATE=1
export GIT_PS1_SHOWUPSTREAM="auto"
PROMPT_COMMAND='__git_ps1 "\h:\W \u" "\\\$ "'