Show git branch in bash prompt

.zshrc

autoload -Uz vcs_info
precmd() { vcs_info }

zstyle ':vcs_info:git:*' formats ' (%b)'
setopt PROMPT_SUBST
PROMPT='%n@%m %1~${vcs_info_msg_0_} %# '

.zshrc_old

# get git branch info using old bash function
# the zsh way to do this is vsc_info
function parse_git_branch {
  git branch --no-color 2> /dev/null | sed -e '/^[^*]/d' -e 's/* \(.*\)/(\1)/'
}

# add git branch version to prompt
setopt PROMPT_SUBST
PROMPT='%n@%m %1~$(parse_git_branch) %# '

gistfile1.sh

function parse_git_branch {
  git branch --no-color 2> /dev/null | sed -e '/^[^*]/d' -e 's/* \(.*\)/(\1)/'
}

export PS1='\h:\W \u$(parse_git_branch)\$ '