[Plugin] only install dependencies for current platform.

Signed-off-by: Eric Wang <skygragon@gmail.com>

Author: skygragon

lib/commands/plugin.js

@@ -1,6 +1,7 @@
 var fs = require('fs');
 var path = require('path');
 
+var _ = require('underscore');
 var request = require('request');
 
 var h = require('../helper');
@@ -66,11 +67,18 @@ function install(src) {
   dststream.on('close', function() {
     log.debug('copied to ' + dst);
 
-    // install dependencies
+    // install dependencies for current platform
     var plugin = require(path.relative(__dirname, dst));
-    if (plugin.deps.length === 0) return;
-
-    var cmd = 'npm install --save ' + plugin.deps.join(' ');
+    var deps = _.map(plugin.deps, function(x) {
+      var parts = x.split(':');
+      if (parts.length > 1 && parts[1] !== process.platform)
+        return '';
+      else
+        return parts[0];
+    }).join(' ').trim();
+    if (deps.length === 0) return;
+
+    var cmd = 'npm install --save ' + deps;
     log.debug(cmd);
     require('child_process').execSync(cmd, {
       cwd: path.resolve(__dirname, '../..')