From 5222d19a11ed0e29d207da0e8c9c8e0e3b18ad78 Mon Sep 17 00:00:00 2001
From: isaacs <i@izs.me>
Date: Sat, 2 Mar 2013 12:25:16 -0800
Subject: [PATCH] stream: Writable.end(chunk) after end is an error

Calling end(data) calls write(data).  Doing this after end should
raise a 'write after end' error.

However, because end() calls were previously ignored on already
ended streams, this error was confusingly suppressed, even though the
data never is written, and cannot get to the other side.
---
 lib/_stream_writable.js              | 31 +++++++++++++++++-----------
 test/simple/test-stream2-writable.js | 16 ++++++++++++++
 2 files changed, 35 insertions(+), 12 deletions(-)

diff --git a/lib/_stream_writable.js b/lib/_stream_writable.js
index 62e0705763..8db4f55a07 100644
--- a/lib/_stream_writable.js
+++ b/lib/_stream_writable.js
@@ -304,10 +304,6 @@ Writable.prototype._write = function(chunk, cb) {
 Writable.prototype.end = function(chunk, encoding, cb) {
   var state = this._writableState;
 
-  // ignore unnecessary end() calls.
-  if (state.ending || state.ended || state.finished)
-    return;
-
   if (typeof chunk === 'function') {
     cb = chunk;
     chunk = null;
@@ -317,17 +313,28 @@ Writable.prototype.end = function(chunk, encoding, cb) {
     encoding = null;
   }
 
-  state.ending = true;
   if (chunk)
-    this.write(chunk, encoding, cb);
-  else if (state.length === 0 && !state.finishing && !state.finished) {
+    this.write(chunk, encoding);
+
+  // ignore unnecessary end() calls.
+  if (!state.ending && !state.ended && !state.finished)
+    endWritable(this, state, !!chunk, cb);
+};
+
+function endWritable(stream, state, hadChunk, cb) {
+  state.ending = true;
+  if (!hadChunk &&
+      state.length === 0 &&
+      !state.finishing) {
     state.finishing = true;
-    this.emit('finish');
+    stream.emit('finish');
     state.finished = true;
-    if (cb) process.nextTick(cb);
-  } else if (cb) {
-    this.once('finish', cb);
   }
-
+  if (cb) {
+    if (state.finished || state.finishing)
+      process.nextTick(cb);
+    else
+      stream.once('finish', cb);
+  }
   state.ended = true;
 };
diff --git a/test/simple/test-stream2-writable.js b/test/simple/test-stream2-writable.js
index efd49021bb..537660263b 100644
--- a/test/simple/test-stream2-writable.js
+++ b/test/simple/test-stream2-writable.js
@@ -311,3 +311,19 @@ test('duplexes are pipable', function(t) {
   assert(!gotError);
   t.end();
 });
+
+test('end(chunk) two times is an error', function(t) {
+  var w = new W();
+  w._write = function() {};
+  var gotError = false;
+  w.on('error', function(er) {
+    gotError = true;
+    t.equal(er.message, 'write after end');
+  });
+  w.end('this is the end');
+  w.end('and so is this');
+  process.nextTick(function() {
+    assert(gotError);
+    t.end();
+  });
+});