title: Cannot do any go command anymore
body: <p>Before it happened, what I am doing is trying to use the <strong>dep</strong> to manage my <strong>golang</strong> code dependency.
  What I found right now is I cannot do any command with <strong>go</strong>, even if I try to uninstall it with <strong>brew</strong> by <code>brew uninstall go</code> and do <code>brew install go</code> again. </p>
  
  <p>If I am doing a <code>go env</code> it will show like this:</p>
  
  <pre><code>$ go env
  go: cannot find GOROOT directory: /usr/local/cellar/go/1.13.1/libexec
  
  $ ls /usr/local/Cellar/go/1.13.8/libexec/
  CONTRIBUTING.md SECURITY.md bin     lib     robots.txt
  CONTRIBUTORS    VERSION     doc     misc        src
  PATENTS     api     favicon.ico pkg     test
  
  $ go version
  go: cannot find GOROOT directory: /usr/local/cellar/go/1.13.1/libexec
  
  $ go build
  go: cannot find GOROOT directory: /usr/local/cellar/go/1.13.1/libexec
  
  $ echo $GOPATH
  /Users/mymac/go
  
  $ echo $GOROOT
  
  $
  </code></pre>
  
  <p>What should I do and check?</p>