今天開發過程中，從master拉下代碼後重啟項目，想用控制臺時，卻發現需要密碼？？並且三次密碼確認後還是瘋狂報錯。

當時第一想到是rvm版本不一致，隨即則檢查了版本跟gem生成，當確認rvm版本無誤時，且強制使用sudo安裝卻需要一條條執行gem install ***安裝gem包時，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.

猜測原因：

rbenv 要往你系統的自帶Ruby裏面安裝gem，但是你的用戶帳戶不允許系統安裝RubyGems，所以要你輸入密碼賦予權限

解決方案（控制臺依次輸入）：

1 echo ‘[[ -s "$HOME/.rvm/scripts/rvm" ]] && . "$HOME/.rvm/scripts/rvm"‘ >>~/.bashrc
2 
3 source ~/.bashrc
4 
5 ruby -v

然後就解決了，可以繼續嗨皮開發了！！

Rvm 進行gem安裝時必須輸入密碼Your user account isn't allowed to install to the system RubyGems 解決方案