patsje.diff

diff --git a/lib/_stream_writable.js b/lib/_stream_writable.js
index 8db4f55..debbab6 100644
--- a/lib/_stream_writable.js
+++ b/lib/_stream_writable.js
@@ -313,19 +313,17 @@ Writable.prototype.end = function(chunk, encoding, cb) {
     encoding = null;
   }
 
-  if (chunk)
+  if (typeof chunk !== 'undefined' && chunk !== null)
     this.write(chunk, encoding);
 
   // ignore unnecessary end() calls.
   if (!state.ending && !state.ended && !state.finished)
-    endWritable(this, state, !!chunk, cb);
+    endWritable(this, state, cb);
 };
 
-function endWritable(stream, state, hadChunk, cb) {
+function endWritable(stream, state, cb) {
   state.ending = true;
-  if (!hadChunk &&
-      state.length === 0 &&
-      !state.finishing) {
+  if (state.length === 0 && !state.finishing) {
     state.finishing = true;
     stream.emit('finish');
     state.finished = true;
@@ -337,4 +335,4 @@ function endWritable(stream, state, hadChunk, cb) {
       stream.once('finish', cb);
   }
   state.ended = true;
-};
+}