install/installer.go
func (i *Installer) GetVersionForBinary(binary string) (version string, err error) {
	log.Println("[DEBUG] running binary", binary)

	content, err := i.commander.Output(binary, "version")
	elements := strings.Split(strings.TrimSpace(string(content)), "\n")
	version = strings.TrimSpace(elements[len(elements)-1])

	return version, err
}
func (i *Installer) GetVersionForBinary(binary string) (version string, err error) {
	log.Println("[DEBUG] running binary", binary)

	content, err := i.commander.Output(binary, "version")
	elements := strings.Split(strings.TrimSpace(string(content)), "\n")
	version = strings.TrimSpace(elements[len(elements)-1])

	return version, err
}
// GetVersionForBinary gets the version of a given Ruby binary