Command.js

command.js

var assert = require('assert');
var spawn = require('child_process').spawn;


module.exports = function Command(command, npmModule) {
  return function(argv, options, loader) {
    var options = {
      env: process.env,
      stdio: 'inherit',
      windowsVerbatimArguments: true
    };

    if (process.platform === 'win32') {
      var quotedArgs = argv.map(windowsQuoteArg).join('');
      var file = 'cmd.exe';
      var args = ['/s', '/c', '"' + command + quotedArgs + '"'];
    } else {
      var file = '/bin/sh';
      var args = ['-c', command].concat(argv);
    }

    return console.log([file].concat(args).join(' '));
    return spawn(file, args, options)
      .on('error', function(er) {
        loader.error('Error running %s (%s), it may need installation, try `npm update -g %s`.',
          command, er.message, npmModule);
      });  };
};

function windowsQuoteArg(arg) {
  arg = String(arg);
  
  // If unnecessary, don't use quotes at all.
  if (!/[ \t"]/.test(arg))
    return ' ' + arg;

  // String contains only spaces. It's sufficient to wrap in quotation marks.
  if (!/[\\"]/.test(arg))
    return ' "' + arg + '"';

  /* String needs to be fully quoted.
   * Expected input/output:
   *   input : hello"world
   *   output: "hello\"world"
   *   input : hello""world
   *   output: "hello\"\"world"
   *   input : hello\world
   *   output: hello\world
   *   input : hello\\world
   *   output: hello\\world
   *   input : hello\"world
   *   output: "hello\\\"world"
   *   input : hello\\"world
   *   output: "hello\\\\\"world"
   *   input : hello world\
   *   output: "hello world\"
   */  
   
  var result = '"';
  var quoteFlag = true;

  for (var i = arg.length - 1; i >= 0; i--) {
    var char = arg[i];

    if (quoteFlag && char === '\\') {
      result = '\\\\' + result;
    } else if (char === '"') {
      quoteFlag = true;
      result = '\\"' + result;
    } else {
      quoteFlag = false;
      result = char + result;
    }
  }

  result = ' "' + result;

  return result;
}

var tests = [
  ['hello"world',     ' "hello\\"world"'],
  ['hello""world',    ' "hello\\"\\"world"'],
  ['hello\\world',    ' hello\\world'],
  ['hello\\\\world',  ' hello\\\\world'],
  ['hello\\"world',   ' "hello\\\\\\"world"'],
  ['hello\\\\"world', ' "hello\\\\\\\\\"world"'],
  ['hello world\\',   ' "hello world\\"'],
];

for (var i = 0; i < tests.length; i++) {
  var t = tests[i];
  assert.strictEqual(windowsQuoteArg(t[0]), t[1]);
}

And I was just trying this with some success... I will read the above.

diff --git a/lib/command.js b/lib/command.js
index 54cfeac..47afa83 100644
--- a/lib/command.js
+++ b/lib/command.js
@@ -8,6 +8,12 @@ module.exports = function Command(command, npmModule) {
       stdio: 'inherit'
     };

+    var cmd = command + " " + argv.join(" ");
+    console.log('cmd:', cmd);
+
+    command = 'cmd';
+    argv = ['/c', cmd];
+
     return spawn(command, argv, options)
       .on('error', function(er) {
         loader.error('Error running %s (%s), it may need installation, try `npm update -g %s`.',