% rm -rf .goenv
$ brew uninstall goenv
$ git clone https://github.com/syndbg/goenv.git ~/.goenv
$ echo 'export GOENV_ROOT="$HOME/.goenv"' >> ~/.bash_profile
$ echo 'export PATH="$GOENV_ROOT/bin:$PATH"' >> ~/.bash_profile
$ echo 'eval "$(goenv init -)"' >> ~/.bash_profile
$ echo 'export PATH="$GOROOT/bin:$PATH"' >> ~/.bash_profile
$ echo 'export PATH="$PATH:$GOPATH/bin"' >> ~/.bash_profile
$ eval "$(goenv init -)"
$ brew install goenv

$ goenv install 1.13.1
$ goenv global 1.13.1
$ goenv rehash
$ goenv versions
system
* 1.13.1 (set by /Users/kanehiroyuu/.goenv/version)
$ eval "$(goenv init -)"

$ go version
go1.13.1 darwin/amd64