use gulp-util isStream

lib/createOutputStream/writeFile.js

@@ -1,13 +1,13 @@
 var fs = require('fs');
 var semver = require('semver');
-var isStream = require('../isStream');
+var gutil = require('gulp-util');
 
 module.exports = function (writePath, file, cb) {
   // if no contents then do nothing
   if (typeof file.contents === "undefined") return cb(null, file);
 
   // stream it to disk yo
-  if (isStream(file.contents)) {
+  if (gutil.isStream(file.contents)) {
     var outStream = fs.createWriteStream(writePath);
     file.contents.once('end', function(){
       cb(null, file);
@@ -21,11 +21,14 @@ module.exports = function (writePath, file, cb) {
     return;
   }
 
-  // write it like normal
-  fs.writeFile(writePath, file.contents, function(err){
-    if (err) return cb(err);
+  if (gutil.isBuffer(file.contents)) {
+    // write it like normal
+    fs.writeFile(writePath, file.contents, function(err){
+      if (err) return cb(err);
 
-    // re-emit the same data we got in.
-    cb(null, file);
-  });
+      // re-emit the same data we got in.
+      cb(null, file);
+    });
+    return;
+  }
 };

package.json

@@ -1,7 +1,7 @@
 {
   "name": "gulp",
   "description": "The streaming build system",
-  "version": "3.1.2",
+  "version": "3.1.3",
   "homepage": "http://github.com/wearefractal/gulp",
   "repository": "git://github.com/wearefractal/gulp.git",
   "author": "Fractal <[email protected]> (http://wearefractal.com/)",
@@ -20,7 +20,7 @@
     "glob-stream": "~3.0.2",
     "mkdirp": "~0.3.5",
     "optimist": "~0.6.0",
-    "gulp-util": "~2.0.0",
+    "gulp-util": "~2.1.0",
     "gaze": "~0.4.3",
     "orchestrator": "~0.2.0",
     "resolve": "~0.6.1",