pyenv/libexec/rbenv-set-default

#!/usr/bin/env bash -e

RBENV_VERSION="$1"
if [ -z "$RBENV_VERSION" ]; then
  echo "usage: rbenv set-default VERSION" >&2
  exit 1
fi

# Make sure the specified version is installed
rbenv-prefix "$RBENV_VERSION" >/dev/null

echo "$RBENV_VERSION" > "${HOME}/.rbenv/default"