今天开发过程中，从master拉下代码后重启项目，想用控制台时，却发现需要密码？？并且三次密码确认后还是疯狂报错。
当时第一想到是rvm版本不一致，随即则检查了版本跟gem生成，当确认rvm版本无误时，且强制使用sudo安装却需要一条条执行gem install ***安装gem包时，就令我抓狂了。
警告提示如下:
Your user account isn't allowed to install to the system RubyGems.
You can cancel this installation and run: bundle install --path vendor/bundle to install the gems into ./vendor/bundle/, or you can enter your password
and install the bundled gems to RubyGems using sudo.
或者如下：
RVM is not a function, selecting rubies with 'rvm use ...' will not work. You need to change your terminal emulator preferences to allow login shell.
Sometimes it is required to use `/bin/bash --login` as the command.
Please visit https://rvm.io/integration/gnome-terminal/ for an example.
猜测原因：
rbenv 要往你系统的自带Ruby里面安装gem，但是你的用户帐户不允许系统安装RubyGems，所以要你输入密码赋予权限
解决方案（控制台依次输入）：
echo '[[ -s "$HOME/.rvm/scripts/rvm" ]] && . "$HOME/.rvm/scripts/rvm"' >>~/.bashrc source ~/.bashrc ruby -v
然后就解决了，可以继续嗨皮开发了！！