无法在rubymine的轨道上安装宝石红宝石

Question

我已经下载并安装了RubyMine。我试图更新宝石，就像在tutorial中所说的那样。一些更新成功，但nokogirl（1.6.5）gem给出了这个错误。有解决方案吗如果这很重要，我有Mac OS X Yosemite。

更新：这些宝石也失败了：actionmailer，actionpack，actionview，jquery-rail，rails，railties，responders。
UPDATE1 我尝试从终端安装它：

sudo gem install rails
nokogiri gem installed, but next were some mistakes.
Fetching: nokogiri-1.6.5.gem (100%)
Building native extensions.  This could take a while...
ERROR:  Error installing rails:
    ERROR: Failed to build gem native extension.