stream: Return self from readable.wrap

Also, set paused=false *before* calling resume().  Otherwise,
there's an edge case where an immediately-emitted chunk might make
it call pause() again incorrectly.

lib/_stream_readable.js

@@ -777,10 +777,12 @@ Readable.prototype.wrap = function(stream) {
   // underlying stream.
   self._read = function(n) {
     if (paused) {
-      stream.resume();
       paused = false;
+      stream.resume();
     }
   };
+
+  return self;
 };
 
 

test/simple/test-stream2-readable-wrap.js

@@ -0,0 +1,94 @@
+// Copyright Joyent, Inc. and other Node contributors.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a
+// copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to permit
+// persons to whom the Software is furnished to do so, subject to the
+// following conditions:
+//
+// The above copyright notice and this permission notice shall be included
+// in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
+// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
+// USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+var common = require('../common');
+var assert = require('assert');
+
+var Readable = require('_stream_readable');
+var Writable = require('_stream_writable');
+var EE = require('events').EventEmitter;
+
+var old = new EE;
+var r = new Readable({ highWaterMark: 10 });
+assert.equal(r, r.wrap(old));
+
+var ended = false;
+r.on('end', function() {
+  ended = true;
+});
+
+var pauses = 0;
+var resumes = 0;
+
+old.pause = function() {
+  pauses++;
+  old.emit('pause');
+  flowing = false;
+};
+
+old.resume = function() {
+  resumes++;
+  old.emit('resume');
+  flow();
+};
+
+var flowing;
+var chunks = 10;
+var oldEnded = false;
+function flow() {
+  flowing = true;
+  while (flowing && chunks-- > 0) {
+    old.emit('data', new Buffer('xxxxxxxxxx'));
+  }
+  if (chunks <= 0) {
+    oldEnded = true;
+    old.emit('end');
+  }
+}
+
+var w = new Writable({ highWaterMark: 20 });
+var written = [];
+w._write = function(chunk, encoding, cb) {
+  written.push(chunk.toString());
+  setTimeout(cb);
+};
+
+var finished = false;
+w.on('finish', function() {
+  finished = true;
+});
+
+
+var expect = new Array(11).join('xxxxxxxxxx');
+
+r.pipe(w);
+
+flow();
+
+process.on('exit', function() {
+  assert.equal(pauses, 10);
+  assert.equal(resumes, 9);
+  assert(ended);
+  assert(finished);
+  assert(oldEnded);
+  assert.equal(written.join(''), expect);
+  console.log('ok');
+});