shell helper： 在不更改shell前提下优化shell体验

add to .bashrc

# add git branch to terminal
# 
# desc
#   first part ${PS1%*\\\$*} is to replcae '...$ ' in previous PS1
#   and then add git branch to last.
#   Insert before conda initialize
# refer:
#   https://stackoverflow.com/questions/15883416/adding-git-branch-on-the-bash-command-prompt
# result
#   (conda_env) user@hostname:~/Desktop/git_repo [master] $

# git 1.9.3 or later: use __git_ps1
PS1='\[\e]0;\u@\h: \w\a\]${debian_chroot:+($debian_chroot)}\[\033[01;32m\]\u@\h\[\033[00m\]:\[\033[01;34m\]\w\[\033[00m\] $(__git_ps1 "\[\033[01;35m\][%s]\[\033[00m\]") \$'
# or
PS1='[\u@\h \w]$(__git_ps1 "[%s]") \$' 

# git < 1.9.3
parse_git_branch() {
    git branch 2> /dev/null | sed -e '/^[^*]/d' -e 's/* \(.*\)/ (\1)/'
}
PS1='[\u@\h \W]$(parse_git_branch) \$'

# some alias
alias nv='watch -n 2 nvidia-smi'
alias gpu='watch -n 2 gpustat'
alias sb='source ~/.bashrc'
alias vb='vim ~/.bashrc'