add tests for passed options to gulp error

test.js

@@ -18,9 +18,9 @@ it('should pass file when it isNull()', function (cb) {
     assert.equal(data, emptyFile)
     cb()
   })
-  
+
   stream.write(emptyFile)
-  
+
   stream.end()
 })
 
@@ -53,17 +53,45 @@ it('should correctly wrap postcss errors', function (cb) {
   stream.on('error', function (err) {
     assert.ok(err instanceof gutil.PluginError)
     assert.equal(err.plugin, 'gulp-postcss')
+    assert.equal(err.showStack, false)
+    assert.equal(err.fileName, "testpath")
     cb()
   })
 
   stream.write(new gutil.File({
-    contents: new Buffer('a {')
+    contents: new Buffer('a {'),
+    path: "testpath"
   }))
 
   stream.end()
 
 })
 
+it('should respond with error on stream files', function (cb) {
+
+  var stream = postcss([ doubler ])
+
+  stream.on('error', function (err) {
+    assert.ok(err instanceof gutil.PluginError)
+    assert.equal(err.plugin, 'gulp-postcss')
+    console.log(err)
+    assert.equal(err.showStack, true)
+    assert.equal(err.fileName, "testpath")
+    cb()
+  })
+
+  var streamFile = {
+    isStream: function () { return true },
+    isNull: function() { return false },
+    path: "testpath"
+  };
+
+  stream.write(streamFile)
+
+  stream.end()
+
+})
+
 
 it('should throw error if processors are not provided', function (cb) {
   assert.throws( function () { postcss() }, gutil.PluginError )