Safer way to judge using mocha cli or not.

Sometimes, It doesn't show coverage for files (node + mocha).
I found that this is not a safe way to judge using mocha cli or not:
```
    var blanketRequired = false;
    if (requireArgPosition &&
        args[requireArgPosition + 1] &&
        args[requireArgPosition + 1].match('blanket')) {
      blanketRequired = true;
    }
```
Sometimes args can be: 
[ 'node', 'C:\Users\miniflycn\AppData\Roaming\npm\node_modules\mocha\bin\_mocha', '--require', 'should', '--timeout', '5000', '--require', 'blanket', '-R', 'html-cov' ]