public function setSshCommand($sshCommand)
    {
        if (empty($sshCommand) || $sshCommand === 'ssh') {
            unset($this->env['GIT_SSH_COMMAND'], $this->env['GIT_SSH']);
        } elseif (!$this->supportsGitSshCommand()) {
            $this->env['GIT_SSH'] = $this->writeSshFile($sshCommand . " \$*\n");
        } else {
            $this->env['GIT_SSH_COMMAND'] = $sshCommand;
        }
    }