Virtualenv-like activate & deactivate for golang. Source this file the normal way from bash to activate the GOPATH, deactivate to deactivate.

activate

export GOPATH="$(cd "$(dirname "${BASH_SOURCE[0]}" )" && pwd)"
export OLDPS1=$PS1
export PS1="[go:$(basename $GOPATH)] $PS1"
alias gcd="cd $GOPATH"
deactivate() {
	export PS1=$OLDPS1
	unset GOPATH
	unset OLDPS1
	unalias gcd
	unset deactivate
}

I forked this to add builtin to the cd. This prevents issues when cd is aliased to something else - for instance, cd() { builtin cd $1 && ls }.

Oh, and I made it work in zsh, too.