From 7793c364fc59a480c94387f8f42681d9e28f2658 Mon Sep 17 00:00:00 2001
From: Dave <dave@jut.io>
Date: Mon, 30 Nov 2015 02:41:51 -0800
Subject: [PATCH] child_process: flush consuming streams

When a client calls read() with a nonzero argument
on a Socket, that Socket sets this._consuming to true.
It never sets this._consuming back to false.
ChildProcess.flushStdio() currently doesn't flush
any streams where _consuming is truthy. But, that means
that it never flushes any stream that has ever been read from.
This prevents a child process from ever closing if one of
its streams has been read from, causing issue #4049. This
commit allows consuming streams to be flushed, and the
child process to emit a close event.

Fixes: https://github.com/nodejs/node/issues/4049
PR-URL: https://github.com/nodejs/node/pull/4071
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
---
 lib/internal/child_process.js                   |  2 +-
 test/parallel/test-child-process-flush-stdio.js | 17 +++++++++++++++++
 2 files changed, 18 insertions(+), 1 deletion(-)
 create mode 100644 test/parallel/test-child-process-flush-stdio.js

diff --git a/lib/internal/child_process.js b/lib/internal/child_process.js
index e93e1ae2e6..04bd270b18 100644
--- a/lib/internal/child_process.js
+++ b/lib/internal/child_process.js
@@ -217,7 +217,7 @@ util.inherits(ChildProcess, EventEmitter);
 function flushStdio(subprocess) {
   if (subprocess.stdio == null) return;
   subprocess.stdio.forEach(function(stream, fd, stdio) {
-    if (!stream || !stream.readable || stream._consuming)
+    if (!stream || !stream.readable)
       return;
     stream.resume();
   });
diff --git a/test/parallel/test-child-process-flush-stdio.js b/test/parallel/test-child-process-flush-stdio.js
new file mode 100644
index 0000000000..5fd7eb3bc9
--- /dev/null
+++ b/test/parallel/test-child-process-flush-stdio.js
@@ -0,0 +1,17 @@
+'use strict';
+const cp = require('child_process');
+const common = require('../common');
+const assert = require('assert');
+
+const p = cp.spawn('echo');
+
+p.on('close', common.mustCall(function(code, signal) {
+  assert.strictEqual(code, 0);
+  assert.strictEqual(signal, null);
+}));
+
+p.stdout.read();
+
+setTimeout(function() {
+  p.kill();
+}, 100);